REL301/302 Firmware Version 1.23 (08/19/03) …€¦ · The Pilot will not trip with RX=0 if the...

REL301/302 Firmware Version 1.23 (08/19/03)Addendum to Instruction book V1.20, 40-386.1F

Revisions

These revisions are to be added (inserted) to the REL301/302 Version 1.20 Instruction Book RevisionHistory as page xvi

Version 1.23 (08/19/03)

1. A change has been done to accommodate a newer generation of communication port switch device. This doesnot affect customer applications.

2. With this firmware revision the applicable RCP version is V2.07.

Version 1.22 (07/20/01)

1 In situations of fault types as zone-1 as well as instantaneous overcurrent, only one LED lights. Nowwith modified logic, LED’s corresponding to all the pickups will light. LCD display, records etc. will notbe affected.

2. Instantaneous over-current tripping was not working according to the setting. This was because of anerror in the associated timer and has been rectified.

Version 1.21 (11/24/99)

Corrected an error in the Blocking system. The Pilot will not trip with RX=0 if the system was first set toPOTT/PUTT/3ZNP and RX1 or RX2 present and then if the system was changed to Blocking.

General corrections in the Instruction Book V1.20 , 40-386.1F:

Page 5:Item 1.5.1:The configuration software RCP for REL301/302 is available at our web sitewww.abb.com/substationautomationselect Transmission products, select REL301/302 and then configuration software.

The waveforms generated by REL301/302 can be viewed by OSCAR or RELTools (RELWave), both ofwhich are available for download along with the above.

Page 8:Some time earlier, an auto reclose catalog version with 120V phase to neutral synch input was added.The sixth digit of the catalog will be with the letter P for this model.

(Existing variations areN for no reclosing,R for autoreclose without synch check,S for reclosing + synchrocheck , 70V phase to neutralT for reclosing + synchrocheck , 120V phase to phase)

Page 97:Changes in autoreclose firmware, V1.27 has necessitated some changes in the overall scheme drawing.Please refer to note 4 to 6 of the drawing.

ABB Automation, Inc.Substation Automation & Protection DivisionCoral Springs, FLAllentown, PA

Instruction Leaflet

Effective: July, 1998Supersedes IL 40-386.1Edated January, 1998

REL 301/302 Version 1.20

Numerical Distance Relay

40-386.1F

ABB Network Partner

ABB Note

Go to Table of Contents to easily access each individual section. Click on the ABB logo to return to the Section TOC page.

REL 301/302 Protection(V 1.20)

REL301/302 REVISION NOTICE

DATE REV LEVEL PAGES REMOVED PAGES INSERTED

5/95 B V1.11

3/96 C V1.12 3-3, 3-9 3-3, 3-9 (Replaced)

12/97 D V1.12 Section 1- 6, 7, 8, 9 Section 1- 6, 7, 8, 9Section 2 - 15, 24, 29, 30, Section 2 - 15, 24, 29, 30,40, 45, 47, 48, 49, 53 40, 45, 47, 48, 49, 53Section 3 - 56, 57, 58, 59, Section 3 - 56, 57, 58, 59,64, 65, 68, 71 64, 65, 68, 71Section 4 - 85, 87, 91, 92, Section 4 - 85, 87, 91, 92,93, 95, 105, 106 93, 95, 105, 106Section 5 - 111, 115, 116, Section 5 - 111, 115, 116,118 118

1/98 E V1.20 Introduction - xvSection 2 - 22, 25, 33, Section 2 - 22, 25, 33,37-54 37-54Section 4 - 91, 92, 94, Section 4 - 91, 92, 94,105 105

7/98 F V1.20 Section 2 - 21, 25, 33, 35 Section 2 - 21, 25, 33, 35Section 4 - 89, 90, 106 Section 4 - 89, 90, 106

CHANGE SUMMARY:

A CHANGE BAR ( ) LOCATED IN THE MARGININDICATES A CHANGE TO THE TECHNICAL CONTENT

iv

I.L. 40-386.1

It is recommended that the user of REL301/302 equipment become acquainted with the information in this in-struction leaflet before energizing the system. Failure to do so may result in injury to personnel or damage tothe equipment, and may affect the equipment warranty. If the REL301/302 relay system is mounted in a cabinet,the cabinet must be bolted to the floor, or otherwise secured before REL301/302 installation, to prevent the sys-tem from tipping over.

All integrated circuits used on the modules are sensitive to and can be damaged by the discharge of static elec-tricity. Electrostatic discharge precautions should be observed when handling modules or individualcomponents.

ABB does not assume liability arising out of the application or use of any product or circuit described herein.ABB reserves the right to make changes to any products herein to improve reliability, function or design. Spec-ifications and information herein are subject to change without notice. All possible contingencies which mayarise during installation, operation, or maintenance, and all details and variations of this equipment do not pur-port to be covered by these instructions. If further information is desired by purchaser regarding a particular in-stallation, operation or maintenance of equipment, the local ABB representative should be contacted.

Copyright © ASEA BROWN BOVERI, ABB Power T&D Company Inc. 1993, 1994, 1995, 1996, 1997, 1998

This document contains information that is protected by copyright. All rights are reserved. Reproduction, adaptation, or translationwithout prior written permission is prohibited, except as allowed under the copyright laws

.

ABB does not convey any license under its patent rights nor the rights of others.

Trademarks

All terms mentioned in this book that are known to be trademarks or service marks are listed below. In addition,terms suspected of being trademarks or service marks have been appropriately capitalized. ABB Power T&D Com-pany Inc. cannot attest to the accuracy of this information. Use of a term in this book should not be regarded asaffecting the validity of any trademark or service mark.

IBM

and

PC

are registered trademarks of the International Business Machines Corporation

WRELCOM

is the registered trademark of the ABB Power T&D Company Inc.

INCOM

is the registered trademark of the Westinghouse Electric Corporation

! CAUTION

I.L. 40-386.1

PREFACE

Scope

This manual describes the functions and features of the REL301(Non-pilot Relay System) and REL302 (PilotRelay System). It is intended primarily for use by engineers and technicians involved in the installation, testing,operation and maintenance of the REL301/302 system.

Equipment Identification

The REL301/302 equipment is identified by the Catalog Number on the REL301/302 chassis nameplate. TheCatalog Number can be decoded by using Catalog Number Table in Section 1.6.6. Both REL301 and REL302can be either vertically or horizontally mounted.

Production Changes

When engineering and production changes are made to the REL301/302 equipment, a revision notation(SUB #) is reflected on the appropriate schematic diagram, and associated parts information.

Equipment Repair

Repair work is done most satisfactorily at the factory. When returning equipment, contact your field sales rep-resentative for RMR authorization. All equipment should be returned in the original packing containers if possi-ble. Any damage due to improperly packed items will be charged to the customer.

Document Overview

Section 1 provides the Product Description. Section 2 presents the Functional Specification. Section 3 presentsthe Setting Calculations. Installation and Operation are described in Section 4. Finally, Section 5 covers Accep-tance Test, Maintenance Test and Calibration procedures.

Contents of Relay System

The REL301/302 Relay System includes the style numbers, listed below, for each module.

Module Style Number

FT-10 Surge Protection- - - - - - - - -1502B35

Backplane Surge Protection - - - - - -1612C53

Option (Reclosing/synch-check) - - - -1613C77

Filter (Input Module) - - - - - - - - - -1612C34

Microprocessor - - - - - - - - - - - -1613C55

Display (Optional) - - - - - - - - - - -1613C69

Power Supply/Relay Outputs - - - - - -1612C68

VT - - - - - - - - - - - - - - - - - - -1612C80

CT - - - - - - - - - - - - - - - - - -1612C79

v

vi

INSTRUCTION MANUAL REL 301/302

TABLE OF CONTENTS

S

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P

AGE

SECTION 1: PRODUCT DESCRIPTION

1. 1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1. 2. REL301/302 FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2.1 Standard Features for REL301 (Non-Pilot) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.2.2 Standard Features for REL302 (Pilot) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.2.3 Optional Features for the Non-Pilot REL301 and Pilot REL302 . . . . . . . . . . . . . . . . . . . . . . . . . 2

1. 3. REL301/302 CONSTRUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.3.1 REL301/302 Outer Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.3.2 REL301/302 Inner Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1. 4. UNIQUE FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.4.1 Fault Detection Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.4.2 Fault Mode and Restricted Fault Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1.4.3 Unique Characteristics of REL301/302 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

1.4.4 Self-checking Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1. 5. UNIQUE REMOTE COMMUNICATION PROGRAM (RCP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1.5.1 ABB Bulletin Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

1. 6. SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1.6.1 Technical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1.6.2 External Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1.6.3 Contact Rating Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1.6.4 Chassis Dimensions And Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

1.6.5 Environmental and Type Test Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

1.6.6 REL301/302 Catalog Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

SECTION 2: FUNCTIONAL DESCRIPTION

2. 1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2. 2 LINE MEASUREMENT TECHNIQUES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.2.1 Single-Phase-to-Ground Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2.2.2 Three-Phase Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

2.2.3 Phase-to-Phase Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

2. 3 MEASUREMENT ZONES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

2.3.1 Zone-1 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

ABB Note

Click on the Section Title to access the desired section. To return to TOC, Click on theABB logo on the first page of each section.

vii

I.L. 40-386.1

2.3.2 Zone-2 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

2.3.3 Zone-3 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.3.4 Zone-1 Extension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2. 4 NON-PILOT OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.4.1 3-Zone Distance Phase and Ground Relay with Reversible Zone-3 Phase and Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.4.2 Inverse Time Overcurrent Ground Backup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

2.4.3 Loss of Potential Supervision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

2.4.4 Loss of Current Supervision (LOI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.5 Fault Detector Overcurrent Supervision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.6 Highset Overcurrent Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.7 Close-Into-Fault Trip (CIFT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.4.8 Unequal-Pole-Closing-Load Pickup Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.4.9 Loss-of-Load Accelerated Trip Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

2.4.10 Current or Voltage Change Fault Detector (

D

I,

D

V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2.4.11 Phase Directional Polarization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2.4.12 Ground Directional Polarization Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

2.4.13 Instantaneous Forward Directional Overcurrent (FDOG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.4.14 Instantaneous Reverse Directional Overcurrent Ground (RDOG) . . . . . . . . . . . . . . . . . . . . . . 25

2.4.15 Programmable Reclose Initiation and Reclose Block Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

2.4.16 Output Contact Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.4.17 Out-of-Step Block Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

2.4.18 Fault and Oscillographic Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.4.18.1 Fault Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2.4.18.2 Oscillographic Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

2. 5 REL302 PILOT SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

2.5.1 Pilot System Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

2.5.1.1 Permissive Overreach Transfer Trip/Simplified Unblocking . . . . . . . . . . . . . . . . . 29

2.5.1.2 Permissive Underreach Transfer Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

2.5.1.3 Directional Comparison Blocking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

2.5.2 Pilot Ground Overcurrent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

2.5.3 High Resistance Ground Fault Supplement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

2.5.4 Instantaneous Reverse Directional Overcurrent Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

2.5.4.1 Supplement to Carrier Ground Start, Blocking Scheme . . . . . . . . . . . . . . . . . . . . 35

2.5.4.2 Pilot Ground Start, POTT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

2.5.5 3-terminal Line Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

2.5.6 Weakfeed Trip Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

2.5.6.1 Weakfeed System Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

2.5.7 Reclose Block on Breaker Failure Squelch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

S

ECTION

P

AGE

viii


2. 6 PROGRAMMABLE CONTACT OUTPUTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

SECTION 3: SETTINGS CALCULATIONS

3.1. MEASUREMENT UNITS AND SETTING RANGES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

3.2. CALCULATION OF REL301/302 SETTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

3.2.1 Ratio of Zero and Positive Sequence Impedances (ZR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

3.2.2 Zone-1 Distance Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57



3.2.5 Overcurrent Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

3.2.6 Out-of-Step Block (OS Block) Blinder Settings (OS Inner and OS Outer) . . . . . . . . . . . . . . . . 60

3.2.7 Timer Settings (Definite Time Setting) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

3.2.8 Timer Settings (Torque Control Overcurrent) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62

3.3. REQUIRED SETTINGS APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

3.3.1 Oscillographic Data (OSC Data) Capture Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

3.3.2 Fault Data (Flt. Data) Capture Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

3.3.3 Current Transformer Ratio Setting (CT Ratio) 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

3.3.4 Voltage Transformer Ratio Setting (VT Ratio) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

3.3.5 Frequency Setting (Freq.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

3.3.6 Current Transformer Type Setting (CT Type) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3.3.7 Read Primary Setting (Read Out) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3.3.8 Ohms Per Unit Distance (X / Dist) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3.3.9 Distance Type (DistUnit) Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3.3.10 Reclosing Mode (RI Type) Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3.3.11 Reclose Initiation Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3.3.12 Remote Breaker Failure, Reclose Block (RemBF RB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

3.3.13 Remote Pilot Control (Pilot) Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

3.3.14 System Type Selection (SystType) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

3.3.15 For The Pilot REL302 Only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

3.3.16 Distance/Overcurrent . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

3.3.17 Step Distance Timers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

3.3.18 Zone-3 Direction Setting (Zone-3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

3.3.19 Positive Sequence Impedance Line Angle (Ang Pos.)* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

3.3.20 Zero Sequence Impedance Angle (Ang Zero)* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

3.3.21 Zero Sequence/Positive Sequence Ratio (ZOL/Z1L)* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

3.3.22 Low Voltage Settings (Low V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

3.3.23 Polarizing Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

3.3.24 Overcurrent Ground Backup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67

3.3.25 Close-Into-Fault Trip Setting (CIF Trip) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

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3.3.26 Load Loss Trip Setting (LL Trip) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

3.3.27 Loss of Potential Block Setting (LOP Blk) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

3.3.28 Loss of Current Block Setting (LOI Blk) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

3.3.29 Trip Alarm Setting (Trip Alm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

3.3.30 Remote Setting (Rem. Set) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

3.3.31 Real-Time Clock Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

3.4. RECLOSE INITIATION MODE PROGRAMMING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

3.4.1 For Non-pilot and Pilot Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70

SECTION 4: INSTALLATION AND OPERATION

4. 1. SEPARATING THE INNER AND OUTER-CHASSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

4. 2. TEST PLUGS AND FT SWITCHES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

4. 3. EXTERNAL WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81

4. 4. FRONT PANEL MAN-MACHINE INTERFACE (MMI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

4.4.1 LED Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

4.4.1.1 LEDs and Display Reset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

4.4.2 Display Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83

4.4.2.1 Front Panel Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

4. 5. JUMPER CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

4. 6. COMMUNICATION PORT(S) USE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

4.6.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

4.6.2 Communication Port Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

4.6.3 Personal Computer Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

4.6.4 Connecting Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87

4.6.5 Relay Password and Setting Change Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

4. 7. FRONT RS-232C COMMUNICATIONS PORT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

4.7.1 Communications Port Set Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

4.7.2 Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

4.7.3 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

4. 8. SIXTEEN FAULT TARGET DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

4. 9. OSCILLOGRAPHIC DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

4. 10. PROGRAMMABLE CONTACT OUTPUTS (Optional Feature) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

4.10.1 Programmable Contact Outputs Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

4.10.1.1 Breaker Failure Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

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SECTION 5: REL301/302 ACCEPTANCE TEST AND MAINTENANCE PROCEDURES

5. 1. NON-PILOT ACCEPTANCE TESTS FOR REL301/302 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

5.1.1 Front Panel Man-Machine-Interface (MMI) Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

5.1.2 Input quantities Verification and Metering Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

5.1.3 “Test Mode” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111

5.1.4 Zone-1 Impedance Accuracy Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113

5.1.5 Input Opto-Coupler Check (Also see Step 12) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

5.1.6 Input Transformer (Ip) Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

5.1.7 Output Contact and Input Circuit Verification Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118

5. 2. PILOT ACCEPTANCE TESTS (FOR REL302 ONLY) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

5.2.1 Non-Pilot Acceptance Tests for REL301/302 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

5.2.2 Input Opto-Coupler Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

5. 3. MAINTENANCE PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

5.3.1 Periodic Maintenance Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121

5.3.1.1 Using Remote or Local Data Communication . . . . . . . . . . . . . . . . . . . . . . . . . . .121

5.3.1.2 Using Man-Machine Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121

5.3.1.3 Routine Visual Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .121

5.3.1.4 Perform the Acceptance Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .122

5. 4. CALIBRATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

5.4.1 Pre-Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

5.4.2 A/D Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122

5.4.3 Real-Time Clock Calibration on Microprocessor Module . . . . . . . . . . . . . . . . . . . . . . . . . . . 123

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LIST OF FIGURES

Section Number Page Number

Section 1

REL 301/302 Layout. (Vertical) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

REL 301/302 Layout. (Horizontal) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

REL 301/302 Outer Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

REL 301 Inner Chassis (Same as REL302) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

REL 301/302 Relay Program Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Section 2

REL301/302 Characteristics/R-X Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Mho Characteristic for Phase-to-Ground Faults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Mho Characteristics for Three-Phase Faults (No Load Flow) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Mho Characteristics for Phase-to-Phase and Two Phase-to-Ground Faults (No Load Flow) . . . . . . . . . . . 39

Logic Drawing Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Zone-1 Trip Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Zone-2 Trip Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Zone-3 Trip Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Zone-1 Extension Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

Inverse Time Overcurrent Ground Backup Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Loss-of-Potential Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

Loss-of-Potential Logic (System Diagram) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Loss of Current Monitoring Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Overcurrent Supervision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Instantaneous Overcurrent Highset Trip Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

REL301/302 Close-Into-Fault Trip (CIFT) Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Special Application for CIF Logic with Time Delay Pickup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46

Unequal-Pole-Closing/Load Pickup Trip Logic & Reverse Block (TBM) Logic . . . . . . . . . . . . . . . . . . . . . . 46

Load Loss Accelerated Trip Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Reclosing Initiation Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Out-of-Step Block Logic (Blinder Characteristics) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

Out-of-Step Block Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

REL302 POTT/Unblocking, PUTT and Blocking Pilot Relay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

REL302 POTT/Unblocking and PUTT Pilot Trip Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

REL302 Channel Sending/Receiving Logic in POTT/Unblocking Schemes . . . . . . . . . . . . . . . . . . . . . . . . 49

REL302 Channel Sending /Receiving Logic in PUTT Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

REL302 Blocking System Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Power Reversal on POTT/Unblocking Schemes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Unequal Pole Closing on Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

REL302 Pilot Ground Trip Supplemented by FDOG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

REL302 Additional Logic for POTT/Unblocking Schemes on 3-Terminal Line Application . . . . . . . . . . . . . 52

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REL302 Additional Logic for PUTT Scheme on 3-Terminal Line Application . . . . . . . . . . . . . . . . . . . . . . . 53

REL302 Weakfeed Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

REL302 Reversible Zone-3 Phase and Ground (Reverse Block Logic) . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

Section 3

% Overreach Resulting from dc Offset Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

CO-2 Curve Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73






CO-11 Curve Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

Overcurrent Reset Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80

Section 4

REL 301/302 Terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95

REL 301/302 Systems External Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

REL 301/302 Systems External Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

REL 301/302 Breaker Failure DC Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

Section 5

Filter (Input) Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124

Power Supply/Output Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125

Microprocessor Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126

Test Connections For:Test Connection for AØ - Ground Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127Test Connection for BØ-Ground Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128Test Connection for CØ-Ground Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129Test Connection for AØ-Ground Test (Dual Polarizing) . . . . . . . . . . . . . . . . . . . . . . . . . . . 130

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Section 2

PHASE AND GROUND SETTINGS (5 tables) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Section 3

TRIP TIME CONSTANTS FOR CURVES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71RECLOSING INITIATION MODE PROGRAMMING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71CURRENT TRANSFORMER SETTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Section 4

SETTING DISPLAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99METERING DISPLAY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102TARGET (FAULT DATA) DISPLAY (2 PAGES) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103PROGRAMMABLE CONTACT OUTPUTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105COMMUNICATIONS CABLE REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106DIP SWITCH SETTING CHART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106RS-PONI (9-PIN) COMMUNICATIONS SPEED SETTING . . . . . . . . . . . . . . . . . . . . . . . . 106

Section 5

FILTER MODULE JUMPER SETTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108POWER SUPPLY MODULE JUMPER SETTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108MICROPROCESSOR MODULE JUMPER SETTINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . 108REL 301 SETTINGS (NON-PILOT SYSTEM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131REL 302 SETTINGS (PILOT SYSTEM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132REL 301/302 REFERENCE DRAWINGS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133


REL301 and 302 Version 1.12

FEATURES ADDED AND IMPROVEMENTS MADE TO VERSION 1.11

1. REL301 and 302

1.1 Changed 3Vo sensitivity from 3 volts to 1 volt for the directional units in order to increasethe sensitivity for zone-2 and zone-3.

1.2 Changed the loss of current blocking (“LOI Blk”) timer from 0.5/0.5 to 10/0.5 seconds inorder to prevent blocking of zone-2 ground distance, zone-3 ground distance for settingsof “T2G” and/or “T3G” are greater than 0.5 seconds and ground backup tripping longerthan 0.5 seconds.

1.3 Improved the loss of potential blocking logic by removing the lead between LOP Timer (8/0) output and AND1G.

1.4 Corrected the angle display for the 1-amp ct application. Now, the angle display is ex-tendedfrom 50% to 10% of the ct rating.

1.5 Extended the front communication access time from 2 to 15 minutes after depressing thefront pushbutton.

1.6 Redefined the programmable contact output signals LLT & TBM to IM & IOM, respective-ly.

1.7 Corrected a software error for the operation of the programmable output contact OC-3.

1.8 Corrected the LV setting for the use of the programmable output contacts. The outputcontacts of LV should be picked up if any one of the voltages fall below the LV setting. Inversion 1.11, the normally open contacts closed if any one of the voltages exceeded theLV setting.

1.9 Improved the accuracy of the programmable contact outputs (PCO) pickup and dropouttimers.

1.10 Improved the accuracy of 3-phase distance tripping by removing KI0 compensation whichwas incorrectly applied to this calculation.

1.11 Corrected LED and Man-Machine Interface targeting mismatch. LED could indicate incor-rect fault type for certain trip operations.

2. REL302

2.1 Changed the RDOG timer from 16/0 to 33/0 ms. For a 3-phase fault at 0% location, theRDOGmay pick up momentarily and may start the TBM (carrier keying); therefore, it maydelay the pilot trip action.

NOTE: For the pilot application, the setting of FDGT should be greater than 3 cycles.

2.2 Removed reclose initiate output from weakfeed trip logic.

xiv

I.L. 40-386.1

SIGNIFICANT CHANGES TO VERSION 1.20 (FROM V1.12)

1. For the setting of Dir Type=Dual Polariz, use current polarizing (3I0 & IP) for the forward directional calcu-

lation (FDOG) when the current IP is greater than 1.0 amp. Use voltage polarizing (3V0 & 3I0) as backup

for the forward direction calculation when the input current IP is less than 1.0 amp.

2. For the settings of LOP Blk=Yes and Dir Type=Dual Polariz, maintain the directionality of Inst. G andground backup GB Dir. (if GB Dir.=Yes) for IP greater than 1.0 amp. Use current polarization of Inst. G and

GB Dir during loss of potential condition.

3. Change loss of potential (LOP) logic by adding 0/16 timer between AND223 and OR221. For time delaytrip units (zone-2, zone-3, etc.) in V1.12, the LOP logic may block the trip on a 3-phase fault if all fault volt-ages (Va, Vb and Vc) are less than 7 volts.

4. Add an inverted input form LOP (0/500 timer) to supervise the AND220. This provides blocking of the dis-tance units for 500 ms after the LOP Block condition is removed.

5. Compensate the time/angle shift due to a long time delay setting (T2 or T3). Accumulated angle measure-ment error may cause the forward directional to reset during a sustained fault.

6. Added a transient block timer of 2 cycles in instantaneous ground trip logic to prevent a trip for a forwarddirection fault occurring immediately after a reverse direction fault.

7. Change the software routine for trip seal-in (TRSL). Any time a high speed trip (HST) occurs, set TRSL.For some cases in V1.12, HST tripped the relay then dropped out before the TRSL set; therefore, the tar-gets were not recorded.

8. For blocking systems only, REL 302 only: Improved channel receive logic security by adding a dropout de-lay of 8 ms for both reciever 1 input (RX1) and reciever 2 input (RX2) which is asserted after RX1 or RX2has been received longer than 3 cycles. This logic change overcomes the problem momentary loss of sig-nal due to the external fault clearing noise.

9. Generate a new signal for programmable contact output logic, 3V0T=(Va+Vb+Vc) which equals logic “1” if3V0T is greater than 105 Vrms.

10. Replace 21Bl and FDOG, with 3V0T and 52a respectively, in the Programmable Contact Output logic table.

11. Change the incremental steps of programmable contact output timers from 10 milliseconds to 1 cycle andchange the settable range from 0-5 seconds to 0-2000 cycles.

xv

40-386.1

1

Section 1. PRODUCT SPECIFICATION

1. 1. INTRODUCTION

The REL 301 and REL 302 relays are numerical transmission line protection systems, withthree zones (four zones in REL 302) of distance protection. All measurements and logic areperformed by an Intel 80C196 microcontroller. Self-checking line voltage and current monitor-ing is included.

1. 2. REL 301/302 FEATURES

1.2.1

Standard

Features for REL 301 (Non-Pilot)

• 100% Numerical processing

• 3-Zone step distance phase and ground relay, with reversible Zone-3 phase and ground; 4impedance units per zone: 3 phase-to-ground; 1 phase-to-phase.

• T1 timer (0 to 15 cycles)

• Independent timers for phase and ground step distance applications

• Overcurrent supervision of phase and ground distance

• Selectable Zone-2 torque controlled phase and/or ground overcurrent

• Inverse time directional or non-directional (selectable) overcurrent ground backup logic

• Loss of potential supervision

• Loss of current supervision

• Instantaneous forward directional phase and ground high set overcurrent trip

• Close Into Fault Trip

• Unequal-pole-closing load pickup logic

• Selectable Loss-of-Load accelerated trip logic

• Selectable Zone-1 extension

• Current change fault detector (

D

I)

• Voltage change fault detector (

D

V)

• Breaker trip circuit test

• Push-to-close test for output contacts

• Binary input test of contact input circuits

• Software switches for functional tests, e.g., (Carrier Send and Carrier Receivers)

• Selectable polarizing for directional overcurrent ground units (zero sequence, negative se-quence and dual

• Programmable Reclose initiation and reclose block outputs

• Fault location capability

• Self-checking software

• Trip contact sealed in by trip current, and selectable dropout delay of 0 or 50 ms

• 16 fault records with setting selectable data capture choices which trigger fault recording

• Real-time clock (Can be externally set with optional IRIG-B interface)

• Low voltage pickup setting for close into fault trip logic

• Setting positive sequence to zero sequence ratio

• Double blinder logic for out of step blocking


2

• Choice of RS (RS 232C Product Operated Network Interface) PONI or NET (INCOM) PONI

• 16 sets of oscillographic data and intermediate target data. Each set includes a graphic dis-play of the 7 analog inputs and 24 digital logic signals. Each oscillographic target contains 1prefault and 7 fault cycles of data. Data collection can be started by TRIP only, TRIP and/orZone2, TRIP and/or Zone 2/ Zone 3 or

D

V

D

I

1.2.2

Standard

Features for REL 302 (Pilot)

• All features listed as standard for the REL 301 are also standard in the REL 302

• Independent pilot zone phase and ground distance units

• Permissive Overreach Transfer Trip (POTT) /Simplified Unblocking Logic

• Permissive Underreach Transfer Trip Logic

• Directional Comparison Blocking Logic

• POTT or Simplified Unblocking Weakfeed Terminal Logic

• Instantaneous Forward Directional Overcurrent Function for High Resistance Ground FaultSupplement to Overreach Pilot

• Instantaneous Reverse Directional Overcurrent Ground Function for Carrier Start on BlockingScheme

• Low voltage pickup setting for weakfeed logic and close into fault trip

• Reclose Block on Breaker Failure Squelch

• 3-Terminal Line Application

1.2.3

Optional

Features for the Non-Pilot REL 301 and Pilot REL 302

• Man Machine Interface (LCD Display)Review or update all settingsReview two most recentLine voltage, current and phase angle monitoring

• RS-232C front communications port

• 5 programmable contact outputs

• Reclosing with or without Synchronism/Voltage Check (See I.L. 40-386.12 for details)

• Up to 4 reclose attempts

• Instantaneous or time delay (each reclose attempt)

• Reset Timer

• Live-Line Dead-Bus/Dead-Line Live-Bus logic

• Synchronism check

• 120 Volt phase-to-phase synchronism voltage input option

1. 3. REL 301/302 CONSTRUCTION

All of the relay circuitry, with the exception of the first-line surge protection, is mounted on theinner chassis, to which the front panel is attached. The outer chassis has a backplane, which isa receptacle for all external connections, including a communication interface. The integralFT-10 switches permit convenient and safe disconnection of trip, ac and dc input circuits, andprovide for injection of test signals.

1.3.1 REL 301/302 Outer Chassis

This is an FT-42 case, where all the input/output signals are surge protected. All external con-nections are made through the rear of the case (except optional front communications port).

40-386.1

3

The outer chassis

(Figure 1-3)

consists of 2 surge protection modules, a backplane surge pro-tection module, a metal case, FT-switches and a communication interface consisting of a Prod-uct Operated Network Interface (PONI) which is either a NET (INCOM

®

) PONI or RS (RS-232C)PONI mounted on the inside of the case on the backplane module.

1.3.2 REL 301/302 Inner Chassis

The inner chassis

(Figure 1-4)

consists of a frame, 2 switchjaws and the following modules.Each module is identified by silk screen label.

•

PT Module:

Consisting of 3 voltage transformers for V

AN

, V

BN

and V

CN

.

•

CT Module

:Consisting of 4 current transformers for IA, IB, IC and IP, where IP is used for zero-sequencedual-polarizing ground current measurement

.

•

Filter Module

:Consisting of the anti-aliasing filters for the seven inputs from the vt and ct modules, the mul-tiplexer to the A/D converter, the A/D converter itself, and the Opto-isolator for the input con-tacts

.

•

Microprocessor Module:

Consisting of a microcontroller (16 bits Intel 80C196 at 10 MHz), two EPROM program mem-ory chips; two RAM chips, an EEPROM for data retention, a real time clock with battery andindication LED’s

.

•

Power Supply (PWRSUP) Module:

This is an isolated switching power supply capable of supplying +5 Vdc for microcontrollerand surrounding IC logic,

±

12 Vdc for reference voltages and + 24 Vdc for communication.All output contacts are on this module

.

Three power supply options are available:48 Vdc125 Vdc250 Vdc

•

Man Machine Interface (MMI)/display module (optional):

consisting of a 2-line, 16 character per line, liquid crystal display (

LCD

), four push-buttons forsetting data entries and a switch for either protection or reclosing information. If the MMI op-tion is not supplied, the switch is supplied for resetting protection or reclosing LEDs from thefront panel.

•

Reclosing/Synch-check Module (optional):

consisting of an independent microcontroller (16 bits Intel 80C196) with its IC logic, signals,contact inputs and outputs

.

1. 4. UNIQUE FEATURES

1.4.1 Fault Detection Software

REL 301/302 fault-detection software operates in two modes: Background and Fault mode.

The REL 301/302 relay normally operates in the “Background mode”. During non-fault operation(Background mode), the REL 301/302 Microprocessor checks hardware, services the man-ma-chine interface including communication port(s), and checks for a disturbances in voltage or cur-rent which indicates a potential fault. If a disturbance is seen, the program switches to the “Faultmode”, for several power cycles, to perform phase and ground unit checks for each zone andlogic functions.


4

The REL 301/302 relay program functions are shown in a flow chart loop

Figure 1-5

, which theMicroprocessor repeats 8 times per power cycle. Most functions are performed all of the time,in the background mode, as shown. An important detail (not shown in

Figure 1-5

) is that manyof the checks are broken into small parcels, so that the whole complement of tasks is performedover a one-cycle period (eight passes through the loop). Some checks are performed more thanonce per cycle (e.g. critical timers).

The REL 301/302 sampling software has 8 states; these states correspond to the sampling rate(8 samples per cycle). Movement from state to state is controlled by a timer. The timer is loadedwith a state time at the beginning of the state.The code executed within a state must be com-pleted before the timer expires. The software then waits for the timer to time out. If the timer ex-pires before the code has completed execution, a time out error results, blocking relay tripping.

The fundamental frequency components are extracted from the samples (each cycle) and con-verted to voltage and current phasor values using a Fourier notch-filter algorithm. During theprocess, the sum of squares of the inputs are accumulated to provide rms values of current andvoltage. The Fourier coefficients and sums are calculated for computing the phase angles. Thesum of squares and the sums of the Fourier coefficients are updated for each sample, using theinformation from the previous seven samples, to provide a full cycle of data.

1.4.2 Fault Mode and Restricted Fault Tests

Upon entry into the fault mode, the sums of the Fourier coefficients and sum of squares fromthe background mode are stored. New sums are obtained, using fault data, to which offset com-pensation has been applied.

To speed up tripping for severe faults, restricted fault testing is implemented. The last half cycleof background mode input samples and the first half cycle of fault mode input samples are usedto compute the current and voltage vectors and rms values. No dc offset compensation is per-formed. High-set instantaneous overcurrent and Zone-1 distance unit tests are executed. Re-stricted fault testing can speed up tripping by as much as one cycle for high current, close-infaults, up to approximately 50% of the setting reach.

Instantaneous overcurrent, inverse time overcurrent protection, and out-of-step blocking arealso conducted during the fault mode and background mode.

For Zone-2 and Zone-3 faults, impedance computation and checking will continue throughoutthe specified time delay. The impedance calculation will be performed once every cycle, in thefault mode and then continued in the background mode.

1.4.3 Unique Characteristics of REL 301/302

A unique characteristic of the REL 301/302 system is its

phase selection principle

. It deter-mines the sum of positive and negative sequence currents for each phase by a novel methodwhich excludes the influence of pre-fault load current. From this information, the fault type canbe clearly identified and the actual distance to the fault can be estimated using a calculationbased on the selected fault type.

High-resistance ground-fault detection

is available in REL 301/302. Sensitive directional pilottripping is activated through an

FDOG Timer.

The pilot ground distance unit is always active andcan have the priority for tripping dependent on the

FDOG Timer

setting.

Load-loss tripping

entails high-speed, essentially simultaneous clearing at both terminals of atransmission line for all fault types, except three-phase, without the need of a pilot channel. Any

40-386.1

5

fault location on the protected circuit will be within the reach of the Zone-1 relays at one or bothterminals. This causes direct tripping of the local breaker without the need for any informationfrom the remote terminal. The remote terminal recognizes the loss of load-current in the unfault-ed phase(s) as evidence of tripping of the remote breaker. This, coupled with Zone-2 distanceor directional overcurrent ground-fault recognition at the remote terminal, allows immediate trip-ping to take place at that terminal by bypassing the remaining zone 2 delay time.

1.4.4 Self-checking Software

REL 301/302 continuously monitors its ac input subsystems using multiple A/D converter cali-bration-check inputs, plus loss-of-potential and loss-of-current monitoring. Failures of the A/Dconverter or any problem in a single ac channel, which unbalances non-fault inputs, causes analarm (AL1 dropped out) and blocks tripping. Self-checking software includes the following func-tions:

a. A/D Converter Check

b. Program Memory Checksum

Immediately upon power-up, the relay does a complete EPROM checksum of programmemory. After power-up, the REL 301/302 continually computes the program memorychecksum.

c. Power-up Volatile RAM Check

Immediately upon power-up, the relay does a complete test of the RAM data memory. Afterpower-up, the REL 301/302 continually performs the RAM check.

d. Non-volatile RAM Check

All front-panel-entered constants (settings) are stored in non-volatile RAM in three identicalarrays. These arrays are continuously checked by the program. If any of the three arrayentrees disagree, a non-volatile RAM failure is detected.

1. 5. UNIQUE REMOTE COMMUNICATION PROGRAM (RCP)

Special remote communications software, RCP is provided for obtaining fault, metering and cur-rent settings data as well as sending data to the REL 301/302. RCP can best be described asa user friendly way of using a personal computer (PC) to communicate with ABB protective re-lays by way of pull-downs menus. By coupling a computer with the appropriate communicationshardware, it is possible to perform all relay setting and data interactions that are possible fromthe man-machine interface. RCP is

required

to communicate with the REL 301/302 via the com-munication port(s). Refer to RCP instruction manual, I.L. 40-603, for detailed information.

1.5.1 ABB Bulletin Board

The ABB Relay Division Bulletin Board (BBS) is now on line. To obtain the latest version of RCPsoftware, please call the ABB BBS via modem at:

(800) 338-0581 or (954) 755-3250

Using configuration settings 300-14,400 bits/second, 8 data bits, 1 stop bit, no parity and fullduplex. Once the connection is established and login is completed, choose L - Library of Filesfrom the TOP menu. Next, select D - Down Load File, from the Library of Files, RCPxxx.EXE(where xxx is the most recent version number e.g. 180 for version 1.80). RCPxxx.EXE is a com-pressed, self extracting file which is expanded and installed by simply typing RCPxxx and fol-lowing the instructions.


6

1. 6. SPECIFICATIONS

1.6.1 Technical

1.6.2 External Connections

Terminal blocks located on the rear of the chassis suitable for #14 square tongue lugs.

Wiring to FT-10 switches suitable for #12 wire lugs.

1.6.3 Contact Rating Data

Trip rated contacts - make & carry 30 amps for 1 second, 10 amps continuously, and break 50watts resistive or 25 watts with L/R =0.045 seconds. Trip rated contacts are:

• Trips A1, A2

• Programmable Contact OC1

• Close outputs Close 1, Close 2

Operating Speed(from fault detection to trip contact close (60 Hz)

Accuracy zone 1,2,3 pilot (302)

ac Voltage (V

Ln

)

ac Current (I

n

)

Rated Frequency

Maximum Permissible ac Voltage (Thermal Rating)

• Continuous• 10 Second

Maximum Permissible ac Current (Thermal Rating)

• Continuous• 1 Second

Minimum Operating Current

dc Battery Voltages

Nominal48/60 Vdc110/125 Vdc220/250 Vdc

dc Burdens: Battery

ac Burdens:

Voltage inputCurrent input

12 msec (minimum)26 msec (typical)33 msec (maximum)

±

5%

60 Hz 70 Volt rms50 Hz 63.5 Volt rms

1 or 5 Amp

50 or 60 Hz

1.5 x V

Ln

2.5 x V

Ln

3 x I

n

100 x I

n

0.1 x I

n

Operating Range38-70 Volt dc88-145 Volt dc176- 290 Volt dc

7 Watts normal30 Watts tripping

0.02 VA at 70 Vac/phase0.15 VA at 5 A/phase

40-386.1

7

All other output contacts are non-trip rated - make and carry 3 amps continuously, and break0.1 amps resistive.

All contacts support 1000 Vac across open contacts

Contacts also meet applicable standards: IEC - 255-6A, IEC - 255-12, IEC -255-16,BS142-1982.

1.6.4 Chassis Dimensions And Weight

Height: 17.875" (453.7 mm)Width: 5.876" (149 mm)Depth: 6.626" (168 mm)Weight: 24 lb (16 kg.)

For Horizontal Mount: 19 inch adapter plate is supplied

1.6.5 Environmental and Type Test Data

Ambient Temperature Range

• For Operation -20

°

C to +60

°

C

• For Storage -40

°

C to +80

°

C

Dielectric Test Voltage 2.8 kV, dc, 1 minute (ANSI C37.90.0, IEC 255-5)

Impulse Withstand Level 5 kV peak, 1.2/50

m

sec, 0.5 joule (IEC 255-5)

Fast Transient Surge Withstand Capability 4 kV, 5/50 nsec (IEC 255-22-6); 5kV 10/150 nsec(ANSI C37.90.1)

Oscillatory Surge Withstand Capability 2.5 kV, 1 MHz (ANSI C37.90.1, IEC 255-22-4)

EMI Volts/Meter Withstand 25 MHz-1GHz, 10-20 V/m Withstand (Proposed ANSI C37.90.2)


8

MOUNTING

Horizontal - - - - - - - - - - - - - - - - - - - - - - - - HVertical- - - - - - - - - - - - - - - - - - - - - - - - - - V

TRIP

3-Pole Trip - - - - - - - - - - - - - - - - - - - - - - - - 3

Self Polarized Ground Distance- - - - - - - - - - - - - - P

CURRENT

1 A - - - - - - - - - - - - - - - - - - - - - - - - - - - - A5 A - - - - - - - - - - - - - - - - - - - - - - - - - - - - B

BATTERY VOLTAGE

48 Vdc - - - - - - - - - - - - - - - - - - - - - - - - - - 4125 Vdc - - - - - - - - - - - - - - - - - - - - - - - - - 1250 Vdc - - - - - - - - - - - - - - - - - - - - - - - - - 2

RECLOSING

Multi-shot Reclosing - - - - - - - - - - - - - - - - - - - RMulti-shot Reclosing w/sync-check, 70V* - - - - - - - - - SMulti-shot Reclosing w/sync-check 120 V** - - - - - - - - TNone- - - - - - - - - - - - - - - - - - - - - - - - - - - N

PILOT SYSTEM

Pilot (REL 302) - - - - - - - - - - - - - - - - - - - - - - PNon-Pilot (REL 301) - - - - - - - - - - - - - - - - - - - N

PROGRAMMABLE CONTACT OUTPUTS

5 Contacts including one trip rated contact - - - - - - - - 5None- - - - - - - - - - - - - - - - - - - - - - - - - - - N

COMMUNICATIONS PORT

(PONI-Rear mounted)INCOM

®

- - - - - - - - - - - - - - - - - - - - - - - - - CRS-232C (Default) - - - - - - - - - - - - - - - - - - - - RRS-232C with IRIG-B Input - - - - - - - - - - - - - - - - B

FRONT PANEL INTERFACE

LCD Display - - - - - - - - - - - - - - - - - - - - - - - LRS-232C port - - - - - - - - - - - - - - - - - - - - - - RBoth - - - - - - - - - - - - - - - - - - - - - - - - - - - BNone- - - - - - - - - - - - - - - - - - - - - - - - - - - N

RELAY COLOR

Black (Default Color) - - - - - - - - - - - - - - - - - - - -Beige - - - - - - - - - - - - - - - - - - - - - - - - - - E

*

70V - Phase to neutral, Sync Input

**

120V - Phase to phase, Sync Input

1.6.6 REL 301/302 Catalog Numbers

M

V 3 B 1 R N 5 C L

REL 301/302 ACCESSORIES

FT TEST PLUGTop or Bottom (Left or Right) . . . . . . . . . . . . . . . ID# 13B8453G05

TEST FIXTUREInner Chassis Test Fixture 5A . . . . . . . . . . . . . . ID# 2678F11G04

SOFTWARERemote Communications Program (RCP). . . . . ID# SWRCP01OSCillographic And Recording (OSCAR) . . . . . ID# SWOSC01

COMMUNICATIONSCabling Kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ID# 1504B78G01

VERTICAL/HORIZONTALConversion Kit . . . . . . . . . . . . . . . . . . . . . . . . . . ID# 2678F11G05

40-386.1

9

2682F39Sheet 1 of 2

Sub 2

Figure 1-1: REL 301/302 Layout. (Vertical)

INS

TR

UC

TIO

N M

AN

UA

L R

EL

301/302

10

2682F39Sheet 2 of 2

Sub 2

8-32 FILLISTER HEAD SCREW(4 SUPPLIED)

Figure 1-2: REL 301/302 Layout. (Horizontal)

40-386.1

11

Figure 1-3: REL 301/302 Outer Chassis.

Rear View Front View

(Use Mounting Stud For Case Grounding) (Inner Chassis Removed)


12

Figure 1-4: REL 301 Inner Chassis (Same as REL 302 vertical mount)

40-386.1

13

ESK00252 dtp

POWER ON

-Initialization-Self-Checks

Mode =Background

START

Sample V and I

dc OffsetCorrection

Compute V and IPhasors Using

Fourier Algorithm

Mode? Fault

Background

Disturbancein

V or

I?

Mode =Fault

Relaying Calculations:Zone 1 and Pilot Zone

Pilot Logic andChannel Control

No Fault for3 Cycles?

Mode =

Background

- Operator Panel Interface

- Hardware Self-Checks

N

Y

N

Y

Relaying Calculations- Zone 2- Zone 3

- Out-of-Step Blinders- Inst. Overcurrent- Ground Backup- Phase Selector

Checks and Logic- Non-Pilot Trip Logic- Loss-of-Pot. And Loss-of-Current- Data Communications- Contact Inputs

D

··

D

- Programmable Output Contact Update

Figure 1-5: REL 301/302 Relay Program Functions


14

RESERVED FOR NOTES

40-386.1

15

2. 1. INTRODUCTION

Both the REL301/302 relay systems detect faults in three zones of phase and ground distance.Zones 1 and 2 are forward set, Zone-3 can be set forward or reverse. REL302 has a separatepilot zone (see

Section 2-5

).

The R-X Diagram,

Figure 2-1

, shows a composite of characteristics available with REL301/302.Zone-1 phase and ground settings are chosen to provide substantial coverage of the protectedline without overreaching the next bus. A setting of 80% of the line impedance is recommended.Faults occurring within the reach of the Zone-1 measurement cause direct tripping without re-gard to any action occurring at the remote terminal.

Zone-2 settings are chosen to assure that faults occurring on the next bus are detected. Settingsare chosen (independent of the Zone-1 settings), generally to be 120 to 150% of the line imped-ance. Any fault occurring on the protected line will be detected by this Zone-2 measurement(within the fault resistance and current limitations of the relaying system settings). Zone-2 trip-ping occurs after a time delay of T2 Definite Time or T2 Torque Control Overcurrent Time, de-pendent on setting choice.

The Zone-3 measurement has a directional setting choice, and may be chosen to respond toforward or reverse faults. The reverse sensing option is used in conjunction with the T3 time de-lay, chosen to coordinate with adjacent terminal(s) Zone-2 timing. The forward sensing optionproduces time delayed backup to other devices sensing forward faults.

Blinder measurements (B1/B4, B2/B3) are available for out-of-step blocking. The inner blindersalso restrict the trip reach of all of the 3-phase fault measuring units (load restriction).

2. 2. LINE MEASUREMENT TECHNIQUES

Line measurement techniques applied to each zone include:

• Single-Phase-To-Ground fault detection

• 3-Phase fault detection

• Phase-to-Phase fault detection

• Phase-to-Phase-to-Ground fault detection

NOTE: IOM is used to supervise all ground units and IM is used to supervise all phaseunits, including Zone 1,2,3 and pilot for tripping.

2.2.1 Single-Phase-to-Ground Fault

Single-phase-to-ground (ØG) fault detection

(Figure 2-2)

is accomplished by 3 quadrature po-larized phase units (ph-A, ph-B, ph-C). Equations 1 and 2 are for operating and reference quan-tity, respectively. The unit will produce output when the operating quantity leads the referencequantity.

(1)VXG IXZ0L Z1L–

Z1L------------------------è ø

æ ö I0+ ZCG–

Section 2. FUNCTIONAL DESCRIPTION


16

(2)

where V

XG

= V

AG

, V

BG

, or V

CG

I

X

= I

A

, I

B

or I

C

Z

1L

, Z

0

L

= Positive and zero sequence line impedance in secondary ohms.I

0

= 1/3(I

A

+I

B

+I

C

)Z

CG

= Zone reach setting (

“Zone1 G”, “Zone2 G”, “Zone3 G”

and

“PilotG”

)

†

in secondary ohms for ØG faultV

Q

= Quadrature phase voltages, V

CB

, V

AC

and V

BA

for ØA, ØB and ØCunits, respectively.

2.2.2 Three-Phase Fault

Three-phase (3Ø) fault detection

(Figure 2-3)

is accomplished by the logic operation of one ofthe three ground units, plus the 3Ø fault output signal from the faulted phase selector unit. How-ever, for a 3-phase fault condition, the distance unit computation will not include zero sequencecompensation. Equations 3 and 4 are for operating and reference quantity, respectively. The unitwill produce output when the operating quantity leads the reference quantity.

V

XG

- I

X

Z

CP

(3)

V

Q

(4)

where V

XG

= V

AG

, V

BG

, or V

CG

I

X

= I

A

, I

B

or I

C

Z

CP


“Zone1 Ø”, “Zone2 Ø”, “Zone3 Ø”

and

“PilotØ”

) in secondary ohms for multi-phase faults.V

Q

= Quadrature phase voltages, V

CB

, V

AC

and V

BA

for ØA, ØB and ØCunits, respectively.

2.2.3 Phase-to-Phase Fault

The phase-to-phase (ØØ) unit

(Figure 2-4)

responds to all phase-to-phase faults, and somesingle-phase-to-ground faults. Equations 5 and 6 are for operating and reference quantity, re-spectively. They will produce output when the operating quantity leads the reference quantity.

(V

AB

- I

AB

Z

CP

)

(5)

(V

CB

- I

CB

Z

CP

)

(6)

where Z

CP


“Zone1 Ø”, “Zone2 Ø”, “Zone3 Ø”

and

“Pilot Ø”

) insecondary ohms for multi-phase faults.

2. 3. MEASUREMENT ZONES

Both REL301 and 302 perform line protection measurements for 3 zones of the transmissionline (Zone-1, Zone-2, Zone-3), and for one optional pilot zone in REL302. When the REL301 or302 system type setting

“SystType”

is set to

“Non Pilot”

, it will perform 3-zone non-pilot pro-tection.

When REL301 and 302 trip, the trip contacts will be sealed-in as long as the trip coil current ex-ists. The trip contact dropout can be delayed by 50 milliseconds, after the trip current is re-moved, by inserting jumper JP4 on the Microprocessor module. See

Figure 5-3

for location.

†

Bold type in quotation marks indicates LCD display quantity.

VQ

40-386.1

17

2.3.1 Zone-1 Trip (Figure 2-5)

For Zone-1 phase faults, the Z1P units will identify the fault and operate. The 3Ø fault logic issupervised by the load restriction logic via AND131C at AND 131. Oversight of zone-1 3Ø triplogic, via AND 131, includes supervision by the selectable out-of-step blocking (OSB) logic (see

Section 2.4.16

) and directional supervised, by the Forward Directional Overcurrent Phase units(FDOPA, FDOPB and FDOPC) for more security during close-in faults. OSB supervision is byboth the OSB logic and the subsequent OSB logic if the option is supplied and is enabled bysetting

“OS Block”

to

“YES”

. Additional 3Ø fault logic supervision is by way of “fault detector”overcurrent input (IM) and loss of potential supervision (LOPBS) at AND 2. Loss of potential su-pervision is enabled by setting

“LOP Blk”

to either

“Yes”

or

“All”

.

Z1P 3Ø output satisfies AND 2B, if

“Zone1 Ø”

is set to any value other than

“Disabled”,

afterthe zone-1 time delay T1 (

“T1 Timer”

if set) has expired and provides a high-speed trip (HST)signal, via OR 2, to operate the trip output relay. The trip circuit is monitored by a seal-in reedrelay (S), which is in-series with each tripping contact circuit. The S relay will pick up if the tripcurrent is higher than 0.5 Amp. The operation of the S contact will turn-on the breaker trip indi-cators (for fault records), and feeds back to OR 4 to hold the trip relay in operation until the powercircuit breaker (PCB) trips and the PCB’s 52a contact opens (not shown in

Figure 2-5

). In theevent a longer duration trip output is required, trip contact dropout can be delayed an additional50 milliseconds, after the trip current is removed, by inserting jumper JMP4 (JP4 on the Micro-processor module). See

Figure 5-3

for location. The trip seal (TRSL) signal plus the output sig-nal from AND 2B turns on the Zone-1 phase trip indicator Zone1 Ø, for targeting plus

ZONE-1

†

and

MØ

LEDs. The breaker trip and Zone-1 phase trip indicators information is stored and/orsealed in. They can be reset by external

R

ESET

‡

voltage or through remote communications.However pushing the

R

ESET

push-button, will only return the display to

“METER”

mode and re-set the flashing LEDs, but the fault target information will remain in memory.

Similar operation occurs for Zone-1 single-phase-to-ground faults. The Z1G units (ØA, ØB andØC) detect faults and operate AND 132, AND 133 or AND134 which are supervised by overcur-rent fault detector IOM and ground directional unit FDOG (forward directional overcurrentground). Zone-1 ground logic AND 3 is also supervised by the signals of ‘NOT’ RDOG (reversedirectional overcurrent ground) or ‘NOT’ UNEQUAL POLE CLOSING or’ NOT’ LOPBS. Thesesignals add security from incorrect operations for close-in reverse faults or operations resultingfrom PCB pole misalignment errors or loss of potential, respectively. Z1G output satisfies AND3B, if

“Zone1 G”

is set to any value other than

“Disabled”,

after the zone-1 time delay T1 (

“T1Timer”

if set) has expired and provides a high-speed trip (HST) signal, via OR 2, to operate thetrip relay. The trip seal (TRSL) signal plus the output signal from AND 3B turns on the Zone-1ground trip indicator Zone-1 G, for targeting plus

ZONE-1

and

ØA

,

ØB

or

ØC

LEDs. Zone-1ground trip indicator information is stored and/or sealed in.

A two-out-of-three “leading phase blocking” logic is included to solve the overreach problem ofthe s ing le -phase ground d is tance un i t s , when and i f they respond to aphase-to-phase-to-ground (ØØG) fault.

The high-speed trip (HST) signal also is connected to the reclosing initiation logic.

2.3.2 Zone-2 Trip (Figure2-6)

For Zone-2 phase faults, the appropriate Z2P

unit will detect the fault and operate the Zone-2phase timer. The timer, denoted T2P in

Figure 2-6 can be selected to be either a definite timedelay or a torque controlled, inverse time overcurrent delay (CO type) characteristic*.

† Bold italic type indicates an output e.g. LEDs or contact output‡ Bold type, with small capital letters, indicates an input e.g. RESET push-button or voltage input


18

*Note: the curves commonly used with electromechanical (e/m) overcurrent relays are a com-posite, average result of considerable testing. Overcurrent characteristics utilized in theREL301/302 are the result of calculations which do not exactly emulate e/m overcurrent relaycharacteristics. Also it should be noted that the time dial setting differs from e/m overcurrent re-lays. E/m relays have a continuously adjustable time dial. REL301/302 attempts to emulate thisfeature by providing time dial settings of 1 to 63 with the middle of the “time dial” range being24 (e/m approximate equivalent of time dial 5).

Timer type selection is a function of setting “T2Ø Type” with choices of “Definite Time” or“Torque Control”. “T2Ø Time” is the related “Definite Time” duration setting. “T2Ø CV”,“T2Ø PkUp” and “T2Ø TC” are the related “Torque Control” overcurrent delay settings. Eachovercurrent delay has a choice of time delay (Reset) or instantaneous (Instant) reset. Z2P out-puts (via AND 4) plus the T2P timer output satisfy AND 18. outputs satisfy AND 2B, The AND18 output provides TDT via OR 3 if “Zone-2 Ø” is set to any value other than “Disabled”. SignalTDT satisfies OR 4 (Figure 2-5) and operates the trip relay. Load restriction, out of step blockingloss of potential and overcurrent supervision are similar to zone-1. The tripping and targetingare similar to Zone-1 trip, except for the Zone-2 phase time delay trip indicator Zone-2Ø

Similar operation occurs for Zone-2 single-phase-to-ground faults. The Z2G units, OR 151 out-put, detects the fault and operates T2G timer. T2G timer options of “Definite Time” or “TorqueControl” are identical to zone-2 phase time delays described above. Operation of IOM ANDFDOG plus operation of T2G provide the TDT signal via OR 3 with Zone-2 ground time delaytrip indicator.

The single-phase ground distance units may respond to a ØØG fault. The output of the Z2G unitplus the operation of the ØØ selection will trip the Zone-2 Ø via OR 157, T2P (“T2Ø Time”) andAND 18. Leading phase blocking, utilized in zone-1 trip logic, is unnecessary for overreachingzones.

The TDT signal is connected to the reclosing block logic.

The settings for Zone-2 timers (phase and ground) are independent, and selected via the manmachine interface as follows:

“If “T2q/ Type” and/or “T2G Type” are selected as “Definite Time” then Table 2 settings ap-ply:

Table 1:

T2f Typeand

T2G Type

Blocked Definite Timeor

Torque Control

Table 2:

T2f Typeand

T2G Type

0.10 to 2.99 Sec (Seconds)

0.10 to 2.99 sec (Seconds

40-386.1

19

If “T2Ø Type” and/or “T2G Type” are selected as “Torque Control” then Tables 3, 4 and 5settings apply:

2.3.3 Zone-3 Trip (Figure 2-7)

For Zone-3, phase faults, the Z3P (“Zone-3Ø”) logic will identify faults in the forward or reversedirection, depending on the “Zone-3” setting, and operate the Zone-3 phase timer T3P. TheZ3P output plus the T3P timer output satisfy AND 20 similar to zone-2. The AND 20 output pro-vides TDT via OR 3. Signal TDT satisfies OR 4 (Figure 2-5) and operates the trip relay. Loadrestriction, out of step blocking loss of potential and overcurrent supervision are similar tozone-1. The tripping and targeting are similar to Zone-1 and Zone-2 trip, except for the Zone-3phase time delay trip indicator Zone-3 Ø.

For Zone-3 single-phase-to-ground faults, Z3G identifies the fault and operates. Z3G, plus op-eration of IOM, satisfies AND 7; operates T3G which provides the TDT signal via OR 3 withZone-3 ground time delay trip indicator delay trip indicator Zone-3 G. For security, the Z3G logicis also supervised by the signal of FDOG, when Z3G is set forward or by the signal of RDOGwhen Z3G is set reverse via logic OR 171B, AND 171C or AND 171D.

Operation for Zone-3 ØØG faults is similar to Zone-2, and is via OR 170, T3P and AND 20 gates.

The TDT signal is connected to the reclosing block logic.

The settings for Zone-3 timers (phase and ground) are independent, and as follows:

• T3P Zone-3 phase timer (“T3 Ø”)0.1 to 9.99 seconds or Blocked

• T3G Zone-3 ground timer(“T3 G”)0.1 to 9.99 seconds or Blocked

Either Zone-3 phase or Zone-3 ground function(s) can be disabled by setting “Zone-3 Ø” and/or“Zone-3 G” to the “Disabled” setting choice or by setting zone-3 phase and/or ground timersto “Blocked”.

Table 3:

T2ø CVand

T2G CV

C0-2; C0-5; C0-6; C0-7; C0-8; C0-9; C0-11Reset or Instant

Table 4:

T2ø PkUpand

T2G PkUp

0.50 to 10.00 Amps

0.50 to 10.00 Amps

Table 5:

T2ø TC and

T2G TC

1- 63

1- 63


20

2.3.4 Zone-1 Extension (Figure 2-8)

This scheme provides a higher speed operation on end zone-faults without the application of apilot channel.

If the REL301/302 “SystType” setting is set to “Zone-1 Extension”, the zone-1 phase/zone-1ground (Z1P/Z1G) unit will provide two outputs; one is overreach which is set at 1.25 x Z1 reachby the microprocessor, and one is the normal Z1 reach. A single shot instantaneous reclosingdevice should be used when applying this scheme. The targets Zone-1 Ø/Zone-1G will indicateeither Z1 trip and/or Z1E trip operations. The other functions (e.g., Z2T, Z3T, ac trouble monitor-ing, overcurrent supervision, unequal-pole closing/ load pickup control, LL trip, etc.) would func-tion the same as in the basic scheme.

For a remote internal fault, either Z1P or Z1G will detect the fault since they are set to overreach.High speed trip will be performed via the normal Zone-1 path (Figure 2-5). HST signal operatesthe instantaneous reclosing scheme. The breaker recloses and stays closed if the fault hascleared.

Target Zone-1 Ø and/or Zone-1 G will be displayed. Once the breaker trip circuit carries current,TRSL operates the 0/5000 timer and satisfies AND 26 for 5000 milliseconds (Figure 2-8). Theoutput signal of AND 26 will trigger the Zone-1 Ø/Zone-1 G reach circuit, constricting theirreaches back to the normal Zone-1 reaches for 5000 milliseconds. During the reach constrictingperiods, if the breaker is reclosed on a Zone-1 permanent fault, it will retrip again. If the breakeris reclosed on an end-zone zone permanent fault, the normal Z2T time delay trip will take place.

For a remote external fault, either Z1P or Z1G will detect the fault since they are set to overreach.High speed trip will be performed. HST signal operates the instantaneous reclosing scheme.The breaker recloses and stays closed if the fault has been isolated by the adjacent line breaker.However, if the adjacent line breaker fails to trip, the normal Zone-2 back up will take place.

NOTE: The reaches of Z1E are based on the Zone-1 settings multiplied by a factor of1.25.

2. 4. NON-PILOT OPERATION

The following features are standard with the REL301/302.

2.4.1 3-Zone Distance Phase and Ground Relay with Reversible Zone-3 Phase and Ground

There are four impedance units per zone: one phase-to-phase unit and three phase-to-groundunits. Zone-3 can be set to forward or reverse for carrier keying or back-up tripping in pilot sys-tem applications.

2.4.2 Inverse Time Overcurrent Ground Backup (Figure 2-9)

The overcurrent ground backup (GB) unit is to supplement the distance ground protection. Itprovides an inverse time characteristic which is similar to the conventional CO characteristics*(Figures 2-32 through 2-38). The time curves, with a choice of time delay (Reset) or instanta-neous (Instant) reset characteristic, can be selected by the “GB Type” Setting. The time dial isset by the “GBT Curve” value. The unit can be selected as directional by using the “GB DIR.”setting and the pickup value is set by “GB Pickup”. The directional GB function uses the torquecontrol approach, as shown. The GB function can be disabled by setting the “GB Type” to “Dis-abled”.

40-386.1

21

Note: The curves commonly used with electromechanical (e/m) overcurrent relays area composite, average result of considerable testing. Overcurrent characteristicsutilized in the REL301/302 are the result of calculations which do not exactly em-ulate e/m overcurrent relay characteristics. Also it should be noted that the timedial setting differs from e/m overcurrent relays. E/m relays have a continuouslyadjustable time dial. REL301/302 attempts to emulate this feature by providingtime dial settings of 1 to 63 with the middle of the “time dial” range being 24 (e/mapproximate equivalent of time dial 5).

The directional unit polarization is determined by the setting of “Dir Type” which can be set to“Zero Sequence”; zero sequence voltage, “Dual Polariz”; zero sequence voltage and/or zerosequence current, or “Negative Sequ” negative sequence voltage and negative sequence cur-rent (see Section 2.4.12, Selectable Ground Directional Unit, Zero Sequence / Negative Se-qu/Dual Polariz).

2.4.3 Loss of Potential Supervision (Figure 2-10)

The ac voltage monitoring circuit is referred to as the loss-of-potential (LOP) circuit. In order toprevent undesirable tripping due to the distance unit(s) operation on loss-of-potential, the follow-ing logic is used:

• (VAN or VBN or VCN <7Vac) or (3Vo>7Vac) and not DI or not (3IO>IOS)

This means that the LOP Block will be set if any one of the phase voltages is below 7 Vac (with-out DI), or if the system detects 3Vo without 3Io (or 3IO > IOS) and without 52b as shown. Theloss-of-potential condition satisfies AND 1. The output signal of AND 1 starts the 8/0 millisecondtimer. The timer output pickups the 0/500 millisecond timer and satisfies AND 1C if there is nooutput from AND 1B. Output signal of AND 1C will block all the distance unit tripping paths viaAND 2, AND 3, AND 4, AND 5, AND 6, AND 172 (also blocks AND 191 and AND 187 for PilotSystems), if “LOP Blk” is set to “YES”. All distance units are blocked from tripping but, theground backup, regardless of it directional setting, and high-set overcurrent units (Inst Ø and InstG) are operative and converted to non-directional operation automatically. If “LOP Blk” is setto “All”, all distance and overcurrent tripping functions will be blocked via AND 8 (Figure 2-5)and the Protection In Service LED will go out. Loss of potential blocking function can be disabledby setting the “LOP Blk” to “No” and the output of the LOP timer will operate the Alarm 1 relay(Failure Alarm) only.

When applying the “LOP Blk” to YES, it is the intent to block all distance units from tripping,should LOP condition exist. However, under a special system condition (refer to Figure 2-11),both circuits are energized without load current; with no source at terminal B, fault near terminalA, Zone-2 relay at terminal B will be blocked by LOP, and may fail to trip. This is because therelay at B sees no current, and a low voltage condition exists before circuit breaker A opens.Another special system condition involves two parallel lines with a symmetrical sources at bothterminals. For an evolving flashover fault, at a point equidistant from both terminals, the conven-tional LOP logic will block trip, because the first external fault generates 3V0 and not 3I0 on theprotected line. Logic AND 1A, 1B, 1C, and 1E 150/0, 3500/200 millisecond timers circuit (in Figure2-10) are for solving these problems. This logic unblocks the LOP circuit and provides a 3500ms trip window for the distance units to trip if the fault current is detected within 150 ms afterLOP has been set. This logic has will be blocked (will have no effect) for the following conditions:

• if DI signal occurs ahead of LOP, or

• if LOP and DI signals occur simultaneously


22

2.4.4 Loss of Current Supervision (Figure 2-12)

The ac current monitoring circuit uses IOM and NOT Vo as criterion, as shown. Under ct shortcircuit or open circuit condition, IOM and NOT Vo satisfies AND 23; the output signal of AND 23starts the 10/0.5 second timer. The timer output turns “ON” the non-memory LOI indicator, whichcan be displayed in the Metering mode, and operates the Alarm 1 relay (Failure Alarm). If theLOI condition exists and “LOI Blk” (LOIB) is set to YES, all trip output will be blocked after the10 second timer times out.

2.4.5 Fault Detector Overcurrent Supervision (Figure 2-13)

For REL301/302, the distance units do not require overcurrent supervision since the relay nor-mally operates in a background mode, zone-1 and pilot impedance computation will not startuntil a phase current or a phase voltage disturbance is detected. This approach minimizes theload current problem when setting the phase overcurrent units. However in order to meet thetraditional practice, a medium set phase overcurrent unit IM (any phase IAM, IBM, ICM) supervisesZone-1ø, Zone-2ø, Zone-3ø and Pilot ø trip functions. This option should not be set to limitZone-3 reach, and traditionally should be set above the load current.

For coordination purposes the ground trip units Z1G, Z2G, Z3G, PLTG, and FDOG are super-vised by the medium set ground overcurrent unit (IOM). The IOS logic and RDOG are used forcarrier send in a Pilot Blocking system (REL302).

2.4.6 Highset Overcurrent Trip (Figure 2-14)

The instantaneous overcurrent units (IAH, IBH, ICH and IOH) are forward directional and sethigh to detect those faults which occur in the Zone-1, therefore, their tripping will occur via OR2 since these trips are classified as high speed trips. These high set trip functions can be dis-abled by setting the “Inst Ø” (ITP) phase and/or “Inst G” (ITG) ground to “Disabled”. The di-rectional characteristic of Inst Ø and Inst G will automatically revert to non-directional protectionif the setting of “Dir Type”=”Zero Seq” or “Negative Seq”, if the LOP condition occurs and thesetting of “LOP Blk” is “YES”. If “LOP Blk” is set to “ALL”, ITP and/or ITG will be blocked. Forthe setting of “Dir Type”=”Dual Polariz” when lp > 1amp, the ITG maintain their directionalitydetermined by the current polarization calculation (3I0 and IP). For IP < 1amp, the directionalityis determined by the voltage polarization calculation (3V0 and 3I0). In order to avoid a false tripduring the clearing of a reverse fault, an ITG transient block logic is added. The ITG trip will bedelayed for 2 cycles if a forward fault is detected immediately after a reverse fault.

2.4.7 Close-Into-Fault Trip (CIFT Figure 2-15a)

There are three low voltage units (LVA, LVB and LVC) in REL301/302. Each unit senses thephase voltage condition in the background mode. The units can be set (“Low V”) from 40 to 60volts, in 1.0 volt steps. For any phase voltage below the set value, the LV logic will produce alogic “1” output signal. The low voltage units are used in CIFT and the pilot weakfeed logic inREL302.

In order to supplement distance unit operation, when the circuit breaker is closed into a fault andline side potential is used, the Close-Into-Fault Trip logic operates as shown in Figure 2-15a. Itincludes logic AND 22, 100/180 millisecond and 16/0 millisecond timers. If any overcurrent unit(IAL, IBL, ICL or IOM) operates OR 11, at the same time as one of the phase voltages (VA,VB,VC) is below the preset level of the LV units, (for 180 ms) after circuit breaker closing (52bcontact opens), then logic AND 22 is satisfied and produces a trip signal. Tripping is classifiedas Time Delay Trip, via OR 3, (Figure 2-6, 2-7) which will produce a Reclose Block signal anda “CIF Trip target”. “CIF Trip” has three setting possibilities: “CIF Trip”, “No CIF Trip” (dis-

40-386.1

23

or “CIF Trip w/Delay” (enable with time delay insertion). The application of close into fault withtime delay, is explained in the following paragraphs.

A modified close into fault logic is employed for the special application shown in Figure 2-15b.Two relays, “looking” in opposite directions, control a single breaker, share a single 52b inputand a common set of voltage transformers. Each relay trips the main breaker and the powertransformer secondary breaker, for faults on the line section being protected (e.g. relay #2 trips52 and 52-2). Classic close into fault logic produced false tripping of one secondary breaker(transformer on the unfaulted line section) upon reclosing after a trip, if the fault persisted. Thiswas due to ‘arming’ of the non-directional, close into fault logic by the common (main breaker)52b, in the relay which did not detect the fault.

The 200/0 millisecond timer delays the ‘arming’ and hence operation of the close into fault logicduring main breaker reclosing. The choice of 200 milliseconds was selected to be greater thanthe 180 milliseconds reset of the 52b, but less than minimum reclose dead time of an instanta-neous reclose. To utilize this logic, the following application rules apply:

1) For relay 1 with “bus-side potential”, that is cts and vts on the same side of the main break-er, set “CIF Trip” to “No CIF Trip”. When bus-side potential is used, close into fault logicis not needed and could misoperate, under certain circumstances, if enabled.

2) For relay 2 with “line-side potential”, that is cts and vts on opposite sides of the main break-er, set “CIF Trip” to “CIF Trip w/delay”. The minimum reclose ‘dead’ time must be greaterthan 200 milliseconds or close into fault tripping will be delayed, and it is possible no closeinto fault trip will occur when reclosing onto a fault.

3) Loss of potential block logic, “LOP Blk” must be set to “Yes” or “No” not “ALL”. For thesetting of “LOP Blk” “ALL”, the relay may not trip during reclosing onto fault since loss ofpotential may set and block tripping.

Standard close into fault trip logic, without time delay, should be selected for all applications withline side potential other than this two-relay-one-breaker scheme configuration.

2.4.8 Unequal-Pole-Closing-Load Pickup Logic (Figure 2-16)

The ground units may pick up on a condition of load pickup or with unequal breaker pole closing.The high speed ground units (Z1G, FDOG and PLTG) should be supervised under this condi-tion. This supervision is achieved by inserting a 0/20 millisecond timer, controlled by the 52bsignal, to supervise the Zone-1G trip via AND 3 (Figure 2-5) PLTG trip via AND 189A (Figure2-20). It should be noted that the 20 ms time delay will have no effect on a normal fault clearing.

2.4.9 Loss-of-Load Accelerated Trip Logic (LL Trip Figure 2-17)

NOTE: The LL Trip function does not need to be set for normal operation of the relay.While it can provide faster tripping for end-zone faults, it may not be used in allsituations. It should be applied with caution based on thorough knowledge of thesystem characteristics where the relay is applied. It is definitely not applicablewhere maximum tapped load may exceed minimum through-load in the protect-ed line.

Load loss accelerated tripping is “acceleration of” or bypassing the remainder of the normalzone-2 time delay after a fault is sensed in zone-2 and the logic detects 3-pole tripping at theremote terminal. Acceleration occurs for all fault types, except 3Ø faults, to improve trip speedfor the sequentially tripping terminal.


24

During non-fault conditions, balanced 3Ø current flowing results in IAL=IBL=ICL= logic “1” whichproduces a logic 1 at the output of AND 24 and OR 13. For a remote fault (beyond zone-1 reach),Z2P OR Z2G detects the fault which satisfies an input to AND 25. However, the signal from AND24 is negated at it’s input to AND 25, therefore, AND 25 should have no output until the remoteend 3-pole trips. At this time, the local end current will lose one or two phases, depending onthe type of fault. The AND 24 output signal changes from “1” to “0” and satisfies AND 25. After10 milliseconds, this output by-passes the remaining T2 timer, and provides accelerated Zone-2trip. The (10/0 millisecond) time delay is for coordination on external faults with unequal poleclearing. The 0/32 millisecond timer is needed for security on external faults without load currentcondition. Target LL Trip will turn on after load loss trip. The load loss trip function is selected bysetting “LL Trip” to “YES”, “FDOG” or “NO”, where “YES” is load loss trip with zone-2 super-vision only; “FDOG” is load loss trip with both zone-2 and (FDOG/IOM) supervision; “NO” dis-ables the load loss trip function.

2.4.10 Current or Voltage Change Fault Detector (DI, DV)

The REL301/302 relay normally operates in the Background mode, while there is no phase cur-rent or voltage disturbances. During background mode, the four input currents (IA, IB, IC and Ip)and the three voltages (VA, VB, VC) are sampled at a rate of 8 per cycle. When a phasedisturbance (DI or DV ) is detected, the relay enters faul t mode for several cy-cles to perform phase and ground unit distance computation for each zone. The criteriafor determining a disturbance in the REL301/302 design are as follows:

1) Each phase D I :if [IKn - I(K-1)n] > 1.0 ampAnd [IKn - I(K-1)n] / I(K-1)n x 100% > 12.5%

2) Each phase DV:if [VKn - V(K-1)n] > 7.0 voltsand [VKn - V(K-1)n] / V(K-1)n x 100% >12.5%

3) D I0 : if [(3I0)Kn - (3I0)(K - 1)n] > 0.5 amp

Where:n = Relative sample number 0,1, 2, 3, 4, 5, 6, 7K = Cycle number relative to a disturbance startK-1 = Cycle number before the disturbance start

2.4.11 Phase Directional Polarization

The phase directional units have no setting selection. Forward phase directionality is derivedfrom the phase angle relationship between the faulted phase current and the non-faultedphase-to-phase voltage. The connection is referred to as a 90˚ connection since the sensedphase current, at a power factor of 1, leads the sensed phase-to-phase voltage by 90˚ undernon-fault conditions. Forward direction operate area can be defined as the faulted phase currentbetween 30˚ leading to 150˚ lagging its 1 power factor position. Directional calculation “maxi-mum torque” output, results when the phase current lags it’s 1 power factor position by 60˚. Of-ten this is referred to as a 90˚ - 60˚ characteristic.

2.4.12 Ground Directional Polarization Selection

The ground directional unit setting “Dir Type” has three selections “Zero Sequence”, “Nega-tive Sequ” and “Dual Polariz”, which sets the polarization of the forward directional overcur-rent ground (FDOG) unit and reversed directional overcurrent ground (RDOG) unit. If “ZeroSequence” is selected, both FDOG and RDOG units will be operated by a zero-sequence volt-age polarizing element. Forward direction is identified by 3I0 leading 3V0 between 30o and 210o.The sensitivity of this element is 3I0 > 0.5 amp and 3V0 >1.0 vac. If “Negative Sequ” is select-

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ed, both FDOG and RDOG will be operated by negative sequence voltage polarizing element.In this case the maximum sensitivity for the forward directional unit is I2 leading V2 by 98o, withV2 >1.0 Vac and 3I2 > 0.5 Amp. If Dual Polarization is selected, the FDOG and RDOG will bedetermined by current polarizing directional element(IP) if the input current IP is greater than 1amp. The IP is connected to FT switch #12 and switch #13 and it is also connected to the powertransformer neutral (ct). The maximum torque angle between 3I0 and IP equals zero degrees,i.e., the forward direction is identified and 3I0 leads IP by 0 to 90 or lags by 0 to 90. The sensitivityof this element is 3I0 > 0.5 and IP > 1.0 amp. If IP is less than 1 ampere, the FDOG will be de-termined by the zero sequence voltage polarizing calculation.

2.4.13 Instantaneous Forward Directional Overcurrent Ground (FDOG) and Phase (FDOP) Units

The instantaneous forward directional overcurrent ground function (FDOG) is a directional unitdepending on the setting of “Dir Type” as described in the preceding Section 2.4.12. FDOG incombination with IOM, supervises Zone-1, Zone-2, Zone-3 Pilot zone ground units for securitypurpose, and also for pilot high resistance ground fault trip (FDOG/Iom).

The phase directional unit (FDOP) is based on the angular relationship of a single-phase currentand the corresponding pre-fault phase-to-phase voltage phasors. The forward direction is iden-tified if the current phasor leads the voltage phasor. The pair of current and voltage phasorswhich are compared are IA and VBA (FDOPA), IB and VCB (FDOPB), IC and VAC (FDOPC). Thethree-phase fault detection of Zone1 and pilot are supervised by FDOPA, FDOPB and FDOPC.The high set currents IAH, IBH, ICH are supervised by FDOPA, FDOPB and FDOPC, respectively.

2.4.14 Instantaneous Reverse Directional Overcurrent Ground (RDOG)

Similar to FDOG, the instantaneous reverse directional overcurrent ground function (RDOG) su-pervises the ground units to prevent false tripping.

2.4.15 Programmable Reclose Initiation and Reclose Block Logic (Figure 2-18)

The REL301/302 system provides the following contact output for Reclosing Initiation and re-closing block functions:

• RI2, used for Reclosing Initiation on trip

• RB, used for Reclosing Block

The operation of RI2 and RB contacts is controlled by the setting of the programmable Reclos-ing Initiation logic. The operation of either RI2, or RB must be confirmed by the signal of TRSL,which is the trip seal of REL301/302 operation.

The most common Reclosing Initiation practice is to have Reclosing Initiation on high speed (Pi-lot, Zone-1 and high set overcurrent) trip only. On Pilot version programming can be accom-plished by closing the EXT. (External) PILOT ENABLE switch and setting the “Pilot” to “YES”.AND 84 will produce logic to operate the RI2 relay when receiving signals from TRSL and AND89.

The program is further controlled by the “RI Type” setting:

“RI Type” setting

NO RI: 3PRN provides no output, therefore, will not operate RI2.


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“RI Type” setting ØG RI:3PRN will provide output “1”on single-phase-to-groundfault only and will operateRI2.

“RI Type” setting ØØ, ØG, RI:3PRN will provide output “1” on single- phase- to- groundfault or 2-phase faults, andwill operate RI2.

“RI Type” setting 3Ø, ØØ, ØØG, ØG RI: 3PRN will provide output “1” on anytype of fault, and will operate RI2.

The Zone-1, Pilot and Highset overcurrent “Fast RI”, “Zone-2 RI” (Z2RI) and “Zone-3 RI”(Z3RI) settings are provided for programming on applications where the Reclosing Initiation onHigh-speed, Zone-2 or Zone-3 trips are desired. Logic AND 62A is controlled by the signal of3PRN, therefore, the setting of “ØG RI”, “ØØ, ØG, RI” and “3Ø, ØØ, ØØG, ØØ RI” also affectthe Fast RI, Zone-2RI and Zone-3RI.

In general, the Reclosing Block (RB) relay will operate on TDT (Time Delay Trip) or OSB(Out-of-Step Block condition). However, it will be disabled by the setting of Fast RI, Z2RI, andZ3RI signal.

2.4.16 Output Contact Test

A “Push-to-Close” feature is included in order to check all output relay contacts, which includeTRIP, BFI, RI2, RB, AL1, AL2, GS, Carrier Send (Pilot), Carrier Stop (Pilot) and each program-mable contact output (if supplied). The relay contact check is supplementary to the self-checkbecause the Microprocessor self-check routine cannot check the output hardware. In order toenable the contact test, jumper JP5 on the Microprocessor module must be in place. (See Sec-tion 5.1.7 for detailed procedures.)

2.4.17 Out-of-Step Block Logic (Figures 2-19a & 2-19b)

The Out-of-Step Blocking (OSB) logic (power swing block supervision) in REL301/302 is a dou-ble blinder scheme. It contains two blinder units, providing 4 blinder lines. (See Figure 2-19b.)The nature of the logic (shown in Figure 2-19a) is that the outer blinder 21BO must operate50ms or more ahead of the inner blinder 21BI, in order for an OSB condition to be identified.Blinder reaches are determined by the setting of “OS Inner” and “OS Outer”, respectively. TheOSB signal is a negated input to the AND 131 (Z1P), AND 147 (Z2P), AND 160 (Z3P), and AND176 (PLTP) for supervising the 3-phase distance tripping. In addition to controlling the OSB log-ic, the blinder units are also used to supervise distance relay tripping (Load Restriction). Phasedistance unit tripping cannot take place unless 21BI operates. This prevents operation of the dis-tance relay on load. The OSB signal is also applied to the reclosing logic for initiating RB.

BlinderLine Polarizing Operating

Left -j(VXG + IXRC (Ang Pos.–90°) IX (Ang Pos.–90°)

Right j(VXG - IXRC (Ang Pos.–90°) IX (Ang Pos.–90°)

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The following quantities are used for the blinder sensing:

whereVXG = Phase to ground voltage, VAG or VBGIX = Phase current in ØA or ØB

RC = Setting of the unit “OS Inner” for 21BI (RT)or “OS Outer” for 21BO(RU).

“Ang Pos.” = The positive sequence line impedance angle.

Operation occurs if the operating voltage leads the polarizing voltage. The characteristics areas shown in Figure 2-19b.

2.4.17.1 Subsequent Out-of-Step Security Logic

Model power system tests, when using a motOR generatOR set, show that the Zone-1 imped-ance unit may overreach or respond to a reversed fault. This was attributed to motOR generatorset instability following delayed clearing on an external fault. The Zone-1 relay, in all cases, iden-tified the fault location and type correctly and responded much later to the swing condition.

Logic was added, OR 131A, AND 131B, AND 131C and OR 122A, utilizing the inner blinder andZone-1 sensing sequence, plus a 50 millisecond timer (as shown in Figure 2-19a) to differenti-ate between a fault and a subsequent out-of-step condition. This logic will not affect normalZone-1 trip time, nor will it affect normal out-of-step blocking.

2.4.18 Fault and Oscillographic Data

The following sections explain the mechanisms for data capture and retrieval. As mentioned inSection 1.5, communication port access requires Remote Communications Program (RCP)software.

2.4.18.1 Fault Data

REL301/302 systems capture the latest sixteen fault data records in non-volatile memory. Thatis, all records are saved even if control power is removed from the system. The two most recentfault data records can be accessed via the front panel MMI. All sixteen fault data records canbe accessed via the communication port(s). Complete details concerning communication portusage is contained in Section 4.6. For a detailed listing of fault data information see Table 4-3.

When a fault occurs, the MMI mode is switched to “L-FLT” mode and is set to provide informa-tion on the most recent fault (Latest Fault). By pressing either the RAISE or LOWER push-buttons,the fault data, for “L-FLT” may be reviewed. Also, when the fault occurs, the LEDs related to“L-FLT” (e.g. ZONE-1 and AG LEDs) flash. LEDs flash, until reset, at a once per second rateindicating one fault record exists, and at a twice per second rate indicating more than one faultrecord exists.

Pressing the SELECT push-button once, will change the MMI display mode to “P-FLT” and allowaccess to the second most recent fault record (Previous Fault). By pressing the RAISE or LOWER

push-buttons, the fault data, for “P-FLT” may be reviewed.

Pressing the RESET push-button will “reset” the LED target indicators and cause the display toreturn the “METER” mode. Pressing the RESET push-button does not erase the stored targetdata.


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Fault data capture is initiated by one of the following selections of “Flt Data” setting:

“Trip” – data captured only if trip action occurs

“Zone-2” – data captured if Zone-2 logic operates or any trip action occurs

“Zone-2, Zone-3” – data captured if Zone-2 or Zone-3 logic operates or any trip action occurs

2.4.18.2 Oscillographic Data

REL301/302 systems capture the latest sixteen oscillographic data records in volatile memory.That is, all records are lost if control power is removed from the system. Oscillographic datarecords can only be accessed via the communications port(s).

Oscillographic data records consist of 8 cycles of 8 analog quantities and 24 digital quantitiestaken at a frequency of eight samples/cycle. The 8 cycles of information is comprised of onecycle of pre-trigger and 7-cycles of post-trigger data.

When the data is retrieved, using RCP, it can be displayed in it’s ASCII tabular form and savedas a file for display at a later time. The file can also be used for graphical display of the user’sdesign or by using the Oscillographic Capture and Recording (OSCAR) software.

Oscillographic data is initiated by one of the following selections in the “OSC Data”:

“Trip” – data taken only if trip action occurs

“Zone-2” – data taken if Zone-2 units pick up or any trip action occurs

“Zone-2, Zone-3” – data taken if Zone-2 or Zone-3 units pick up, or any trip action occurs.

“dV or dI” – data taken if DI, DV, Zone-2 or Zone-3 units pick up, or any trip actionoccurs

NOTE: See Section 2.4.10 for DV D I definition.

2. 5. REL302 PILOT SYSTEM

NOTE: The external Pilot Enable Switch (PLT ENA) must have voltage applied in conjunc-tion with the “Pilot” setting set to “Yes” to enable the pilot system.

2.5.1 Pilot System Type

As mentioned in Section 2.3.4, choice of system type is controlled by the setting “Syst Type”.Both the REL301/302 have system type selection settings as shown below:

• “Non Pilot” –3 zone distance (REL301 and REL302)

• “Zone-1 Extension” –(REL301 and REL302)

• “POTT” –Permissive Overreach Transfer Trip/Simplified Unblocking(REL302 only)

• “PUTT” –Permissive Underreach Transfer Trip (REL302 only)

• “Blocking” –Directional Comparison Blocking (REL302 only)

The following settings are recommended for POTT and BLOCKING systems:

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• “Osc Data” –Zone-2, Zone-3

• “Flt Data” –Trip

• “FDOGTime” –3 cycles or longer

• “Pilot Ø” & “Pilot G” –150% overreach the next bus

• “Zone-1 Ø” & “Zone-1G” –80% of the protected line

• “Zone-3 Ø” & “Zone-3G” –100% of the reversed line

• “Zone-3” –Reverse Dir. (required setting)

2.5.1.1 Permissive Overreach Transfer Trip/Simplified Unblocking (Figures 2-20, 2-21, 2-22)

If the system type setting “Syst Type” is set to “POTT”, REL302 will perform either the POTTscheme or the Simplified Unblocking scheme, depending on the applied pilot channel.

The basic operating concepts of a POTT scheme are:

1) Pilot distance measurement units PLTP and PLTG (“Pilot Ø” and “Pilot G”) are set tooverreach the next bus.

2) Pilot channel is a frequency shift type device; its signal may be through either metallic wire,leased telephone circuits, power line carrier, microwave or fiber optic channels.

3) Transmitter frequency should be different at each terminal: channel is normally operatedon a guard frequency; and the channel frequency will be shifted from guard to trip when thepilot relay(s) are operated; and pilot trip is performed when the pilot relay(s) operate and apilot trip frequency signal from the remote end is received.

The basic operating concepts of a Simplified Unblocking scheme are the same as the POTTscheme, except for differences in applied pilot channel equipment. In an unblocking scheme, thepilot channel is a frequency-shift type power line carrier. The transmitter frequency must be dif-ferent at each terminal. It is normally operated on a blocking frequency and will be shifted to anunblocking frequency when the pilot relay(s) operate. The carrier receiver should provide logicfor which, in the event of loss-of-channel or low SNR ratio, the pilot trip circuit is automaticallylocked out after a short time delay. Pilot trip is provided, however, if the tripping distance relay(s)operate during this short time period between loss-of-channel and pilot trip lockout. PulsarTechnologies Inc. type TCF-10B Power Line Carrier receiver provides this logic; it provides a150 ms trip window, then automatic lockout after loss-of-channel. Provision for a secondhigh-speed pilot trip is provided, for the situation when a permanent fault causes a permanentloss-of-channel and the breaker closes onto the fault.

The operating concepts of the pilot distance measurement units PLTP and PLTG are the sameas for the non-pilot zone distance measurement units, and are supervised by the same LOPBS,OSB, IOM, FDOP, and FDOG units, as shown in Figure 2-20. The pilot phase and/or pilotground function(s) can be disabled by setting the “Pilot Ø” and/or “Pilot G” to “Disabled”.

The POTT and Simplified Unblocking schemes include the following types of logic:

a. Tripping logic (Figure 2-21)

1) For a forward external fault, the local pilot distance measurement units PLTP or PLTG de-tect the fault, operates and keys the pilot channel. The output from OR 40 will satisfy thefirst input to AND 30. Assuming that TBM (POTT) does not operate and PILOT ENABLE(see Figures 2-21 and 2-31 for definition) is set, then three out of four inputs of AND 30


30

are satisfied, but pilot trip cannot occur since the remote transmitter is still sending a guard(or blocking frequency) signal. CR input to AND 30 is not satisfied.

2) For an internal fault, the pilot relays at both ends PLTP or PLTG, or the zone-1 relays Z1Por Z1G, detect the internal fault and operate and together with the received trip (or unblock-ing frequency) signal CR, via AND 44 (Figure 2-22), satisfy AND 30 (Figure 2-21). PT(Pilot Trip) output of AND 30, will cause high speed tripping via OR 2 (Figure 2-5). Targetsof pilot phase trip or pilot ground trip will result after the breaker trips (TRSL).

b. Carrier Keying Logic (Figure 2-22)

1) Forward Fault Keying

For a forward internal or external fault, the local pilot relays PLTP or PLTG, or the zone-1relays Z1P or Z1G, detect the fault operates OR 40 or OR 25, and causes pilot channelSEND reed relay to operate, via AND 35, if PILOT ENABLE is set. Operation of the SENDrelay will key the local transmitter, shift the transmitting frequency from guard to trip (or froma blocking to an unblocking), which allow the remote pilot relay system to trip.

2) Echo Keying

Since the POTT and the Simplified Unblocking schemes require the receiving of a permis-sive signal from the remote end, for pilot trip, provision is made for the condition when theremote breaker is opened.

When the breaker is opened, three of the inputs of AND 34B (Figure 2-22) are satisfied bythe NOT FORWARD (from OR 14), NOT REVERSE (from POTT-TBM) and 52b. Channelreceive from either RCVR-1 (2 terminal system configuration) or RCVR-1 and RCVR-2 (3terminal system configuration, Figure 2-28) will produce an output from AND 34B (ECHO)which will cause a SEND signal via OR 18. This echo keying will be continue for 150 milli-second or less if any inputs to AND 34B change state (e.g. receive input stops).

3) Signal Continuation

This logic includes an input from the TRSL signal and a 0/150 millisecond (ms) timer. The0/150 ms signal continuation time is required to keep the local transmitter at the trip fre-quency (or unblock frequency) for 150 ms after the local end high speed trips which in-cludes pilot trip, zone-1 trip, and high-set overcurrent trip, in case of sequential trip on thesystem. This logic will be disabled by a time delay trip (TDT) for 300 ms after the trip deci-sion (AND 34A), and will be blocked from operation by close into fault trip (CIF, AND 49A).

c. Carrier Receiving Logic (Figure 2-22 and 2-28)

This logic includes RCVR-1 input, OR 15, AND 63 and AND 44, for 2 terminal system configu-ration. RCVR-2 input is through OR 21 from AND 63A (Figure 2-28) for 3 terminal system con-figuration. Output “trip” (or unblocking) frequency signal from the channel receiver operates thelogic and produces a channel receive (CR) signal.

d. Channel Indicators (Figure 2-22)

The target indicating channel send “Car Send”, will be stored after the send decision has beenmade and the breaker trips. The target indicating a receive operation, “Rx Ch1” will be storedafter the breaker trips and a carrier trip signal is received from the receiver.

e. Reverse (Transient) Block and Unblock Logic (TBM, Figure 2-16)

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For a loop system or a parallel line application, power reversal may introduce problems for a pilotrelay system especially when a 3-terminal line is involved, since the pilot distance units mayhave to be set greater than 150% of the line impedance in order to accommodate the infeed ef-fect from the tapped terminal. Pilot distance units may operate for an external fault on the parallelline when the third source is out of service. The TBM block and unblock logic solves this prob-lem.

There are some other typical cases of the protected line being tripped by a ground directionalrelay upon clearing of a fault in the adjacent (but not parallel) line. When the adjacent line break-er trips, it interrupts the current in the faulted phase as well as the load current in the unfaultedphases. Dependent on the direction of this load current, and the contact asymmetry of thebreaker, there can be a short pulse of load-derived Io with possible “tripping direction” polarity,which provides an electrical forward-torque to the ground directional relay. Therefore, it is de-sired to increase TBM security by adding the transient block timer (0/50) logic. This security isincluded automatically for POTT schemes. Note for the TBM logic to function correctly:Zone-3 must be set in the reverse direction (“Zone-3” set to “Reverse Dir.”), zone-3 phase(“Zone-3 Ø”) and zone-3 ground (“Zone-3 G”) distance, should be set to 100% of the re-verse line impedance.

f. Channel Simulation (Figure 2-22)

The MMI “TEST” mode provides the capability to simulate the SEND (“SEND”) logic for keyingaction without the operation of pilot relay units. Also receiver inputs 1 (“Rx1”) and 2 (“Rx2”,Figure 2-28) can simulate receiving of a permissive trip or unblocking frequency signal withoutthe operation of the remote transmitter. Receiving of both channels can be simulated if “Rx1,Rx2” is selected. See Section 5.2 for details.

g. Programmable Reclosing Initiation (Figure 2-18)

The basic programmable reclose initiation application is as described in Section 2.4.14. How-ever, on pilot systems, to activate the reclose initiate output RI2, for any high-speed trip, the EXT.PILOT ENABLE SW. (Figure 2-18) must be satisfied, and the setting “FAST RI” should be setto “Pilot/Z1/Inst I”. The operation will occur via the logic AND 89, AND 84 as shown in Figure2-18.

2.5.1.2 Permissive Underreach Transfer Trip (Figure 2-23)

If a permissive underreaching transfer trip (PUTT) system is desired, the system type setting“Syst Type”, is set to “PUTT”. Basic operating concepts of a PUTT scheme are:

1) Pilot distance measurement units PLTP and PLTG (“Pilot Ø” and “Pilot G”) are set tooverreach. The pilot channel is a frequency-shift type device, and the transmitter frequencyis different at each terminal.

2) The pilot channel is normally operated with a guard frequency, the channel frequency willbe shifted from guard to trip when the zone-1 distance measurement units Z1P or Z1G op-erate, and pilot trip is performed when the pilot relay PLTP or PLTG operates, together withthe receiving of a carrier trip signal from the remote end.

PUTT includes the following logic:

a. Pilot Tripping Logic


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The Pilot Tripping Logic for the PUTT scheme is the same as for the POTT scheme (Figures2-20, 2-21).

b. Carrier Keying Logic

1) Forward fault keying (Figure 2-23)

For a forward end zone fault, the PUTT scheme will not key except when the internal faultis within the zone-1 reach. This means that the PUTT scheme keys only on Zone-1 faults.Keying is via AND 46, AND 33, OR 18 and AND 35.

2) Signal continuation (Figure 2-23)

Same as for POTT scheme.

The TBM logic is not required because the carrier keying units are set to underreach.

NOTE: For open breaker condition, the echo keying will not work due to lack of the“SEND” signal from the remote terminal for an end zone fault. The remote termi-nal relies on Zone-2 to clear the fault.

c. Programmable Reclosing Initiation (Figure 2-18)


d. Carrier Receiving Logic (Figure 2-29)

Same as for POTT scheme except as shown.

e. Channel Indicators (Figure 2-22)

Same as for POTT scheme except recorded as PUTT.

2.5.1.3 Directional Comparison Blocking (Figure 2-24)

If a directional comparison blocking (Blocking) system is desired, the system type setting “SystType”, is set to “Blocking”. Refer to Section 2.5.1 for other recommended settings for Blockingsystems. Basic operating concepts of a Blocking system are:

1) Pilot distance measurement units PLTP and PLTG (“Pilot Ø” and “Pilot G”) are set tooverreach the and the zone-3 distance measurement units Z3P/Z3G (“Zone-3 Ø”/”Zone-3G”) must be set in the reverse direction to detect reverse external faults for carrier start andReverse Block Logic (TBM).

2) Pilot channel is an “ON-OFF” type power line carrier. Transmitter frequency at each termi-nal can be the same. Channel is normally OFF until a disturbance is detected (DV, DI) whichwill cause a SEND output for a minimum of 65 milliseconds via AND 50. Continued sendingwill occur as the result of any reverse logic operating via OR 41 and continuation for 50 mil-liseconds after the reverse logic resets.

3) Pilot tripping is performed when pilot distance measurement units operate and a carrierblocking signal is not received.

The Blocking system, as shown in Figure 2-24, includes the following logic:

a. Tripping Logic (Figure 2-24)

1) For a forward internal fault, the local pilot distance measurement units PLTP or PLTG de-tect the fault and which causes an output from OR 40 stopping the channel send circuit (DI,DV starts the carrier before the distance measurement units operate), via OR 16, SQ timer(0/150 ms) and AND 50. (The receiver receives the signal from both local and remote trans-

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mitters.) At the same time, output of OR 40 will satisfy one input of AND 48 and also startsthe Channel Coordination Timer (BLKT). (See Section 3.2.7e for BLKT setting.) After thepreset time of the channel coordination timer, logic AND 47 will satisfy AND 48, if there isno received carrier signal from either remote or local, and if the local transient block is notset (0/50 timer input to AND 51). If PILOT ENABLE (Figure 2-21) and AND 48 are satisfied,AND 52 will produce pilot trip. Pilot trip target would be recorded the same as for POTT.

2) For a forward external fault, the local pilot distance measurement units PLTP or PLTG de-tects the fault and operates in the same manner as for a forward internal faults. However,at the remote terminal, the carriers units DI/DV/ Reverse Z3P/Z3G/RDOG also detect thisexternal fault and operates the SEND relay, which keys the carrier transmitter, sending theblocking signal to the remote terminal(s) via OR 41, AND 51, OR 18, and AND 35. The localreceiver receives the blocking signal, disables the output of AND 47; and prevents pilot trip-ping.

3) A timer 50/8 and OR47 are added between the RCVR and AND47. This logic is to over-come the fact that the receiver (RCVR) input may drop out momentarily due to the externalfault clearing noises.

b. Carrier Keying Logic

1) Reverse fault keying (Figure 2-24)

2) For a reverse fault, the DI and DV will operate and begin transmitting the blocking signaland if local reverse “looking” measurements units, Reverse Z3P/Z3G or RDOG detects thefault, operation of the Send relay, continues sending the blocking signal to the remote ter-minal(s).

NOTE: The use of DI and DV for carrier start provides more security to the blockingscheme by starting carrier in approximately 4-6 milliseconds.

3) This SEND circuit includes logic AND 173, OR 41, AND 51, AND 50, OR 18 and AND 35.The logic of OR 222A and the 32/0 ms timer circuit is to stop the internal fault SEND on aweakfeed terminal condition.

4) Since the present keying practice on carrier systems use either the contact open (negativeor positive removal keying) or contact close (positive keying) approach, a form-C dry con-tact output for SEND is provided in REL302.

5) Signal continuation and TBM logic

For a reverse fault, both the local carrier start relay(s) and the remote pilot relay(s) detectthe fault and operate. The local carrier start relay(s) start the carrier and send a blockingsignal to block the remote pilot relay from tripping. After the fault is cleared by the externalbreaker, the remote breaker may have a tendency to trip falsely if the carrier start unit re-sets faster than the pilot trip unit. The 0/50 ms timer between the AND 41D and AND 51continues the SEND signal for 50 ms after the carrier start units have been reset. This logicalso provides transient block and unblock (TBM) effect for power reversal on parallel lineapplications.

The subsequent out-of-step condition, as described in Section 2.4.17.1, may cause the re-verse looking units to fail to operate on external faults, and introduce false pilot tripping atthe remote terminal(s). Additional logic has been added to the design which includes OR41C, 32/0 ms timer, AND 41B and OR 41 to prevent false tripping. It utilizes the not FDOP(or FDOG) and LV condition (LV units can be set between 40 and 60 volts) to initiate theTBM circuit; and sends a blocking signal to the remote terminal(s). Setting “OS Block” to“YES” supervises AND 41B when this additional logic is required.


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6) Internal fault preference and squelch

On a close-in fault, the carrier start logic may operate and start the transmitter. This oper-ation may block the system from pilot tripping. The negating signal from OR 16 to AND 50will provide an internal fault preference feature to prevent this problem. The squelch 0/150millisecond timer is required for improving the problem if the local breaker tripped fasterthan the remote breaker on an internal fault. The logic prevents SEND from operating for150 ms after any high speed tripping, including pilot trip, zone-1 trip and instantaneousovercurrent trip.

c. Channel Receiving Logic (Figure 2-24)

Channel receive signal, from the receiver output, will be directly applied to AND 47 to disablethe pilot tripping function.

d. Channel Indication (not shown in Figure 2-24)

Since the carrier channel turns “ON” for external faults only, the channel indicators for send andreceive will not be recorded.

e. Channel Simulation


f. Programmable Reclosing Initiation (Figure 2-18)


2.5.2 Pilot Ground Overcurrent

Pilot Ground Overcurrent Supplement is added for high resistance faults and improves securityon POTT/unblocking schemes on some special power system conditions, such as shown in Fig-ure 2-25. A ØØG fault is on the paralleled line section. Due to the system condition, fault currentflowing in the protected line would be I1+I2 from A to B, and Io from B to A. The operation ofpilot distance relays would be a phase relay at A and a ground relay at B. The result would beerroneous directional comparison of an external fault as an “internal” one. The POTT/unblockingscheme will incorrectly trip the protected line.

REL302 POTT/Unblocking pilot ground unit is supervised by the reverse-looking ground unitRDOG as shown in Figure 2-31 (REVERSE BLOCK LOGIC). At terminal A, the RDOG disablesthe PILOT KEY and PILOT TRIP functions via AND 35 and AND 30. Terminal B will not receivea signal for permissive trip since none is sent. The reverse-block logic also provides the conven-tional TBM feature to prevent false operation on power reversal. It should be noted that aBLOCK-THE-BLOCK logic is also included in the circuit, as shown in Figure 2-31. TheBLOCK-THE-BLOCK logic is to prevent the REVERSE BLOCK LOGIC from over-blocking. If thebreaker is unequal-pole closing on a ØØG fault, say pole-A, pole B and C close at a later time(see Figure 2-26). If, due to breaker contact asymmetry, the first breaker contact to close is theone of the faulted-phase, the zero-sequence (or negative sequence) polarizing voltage will ini-tially have a polarity opposite to its fault-derived polarity. Reverse looking ground unit couldpick-up, start the reverse block logic and maintain it for 50 ms causing the correct tripping to bedelayed. The BLOCK-THE-BLOCK logic prevents this delay. The Reverse Block Logic also in-cludes the reverse looking Zone-3 Ø /Zone-3 G (Z3P/Z3G) logic as shown in Figure 2-31.

40-386.1

35

2.5.3 High Resistance Ground Fault Supplement (Figure 2-27)

Supplemental protection is provided on overreaching pilot systems to detect high resistanceground faults. The instantaneous forward directional overcurrent ground function FDOG worksin conjunction with the pilot ground distance unit. The FDOG directional unit operation is deter-mined by the setting of “Dir Type”. Refer to Section 2.4.12 for the setting of “Dir Type”. FDOGis supervised by the “Iom” setting. A coordination timer “FDOGTime” (FDGT) is provided toallow preference for pilot ground distance unit operation. The delay time can be set from 0 to 15cycles in 1 cycle steps. It is recommended to set the “FDOGTime” to 3 cycles or longer due tothe sensitivity of FDOG.

2.5.4 Instantaneous Reverse Directional Overcurrent Ground

Similar to FDOG, the instantaneous reverse directional overcurrent ground function RDOG sup-plements the pilot zone logic.

2.5.4.1 Supplement to Carrier Ground Start, Blocking Scheme

In the blocking system, RDOG, supervised by IOS, provides additional ground fault detection(high resistance) beyond what is available by Z3G (reverse looking) for carrier start.

2.5.4.2 Pilot Ground Start, POTT

In the POTT/UNBLOCK systems, RDOG supervises PLTG and prevents keying or tripping onreverse faults.

2.5.5 3-terminal Line Application

For Blocking 3-terminal line applications, since the frequency of the 3 transmitters are the same,any one transmitter starting will block the pilot system from tripping, therefore, logic for the 3-ter-minal pilot system would be the same as that used for the 2-terminal system. However, forPOTT/Unblock and PUTT systems, since the transmitter frequencies are different at each ter-minal, logic for the second receiver (RCVR-2) is added to the system when the application in-volves 3-terminal lines. Setting “3-Term.” should be set to “YES” when a 3-terminal line systemis required.

a. Additional Logic For POTT and Simplified Unblocking (Figure 2-28)

This logic includes a contact converter (CC) for RCVR-2, AND 55, and logic for the secondreceiver indication (not shown). Voltage applied to RCVR-2 operates the contact converterand produces the channel receive signal (CR) from AND 63A via AND 55 and AND 64which allows pilot tripping (Figure 2-22, OR 21).

b. Additional Logic for PUTT (Figure 2-29)

The additional logic for PUTT is similar to that described for POTT scheme, except logicincludes AND 56, AND 57 and 50/0 millisecond timer. Since Zone-1 reach dictates trans-mitting of the permissive signal, the fault could possibly be detected by only one remoteterminal. For a close-in Zone-1 fault, only the local terminal can key its transmitter and theother two may not. This logic provides a CR pilot trip signal for 50 ms for, system security,if either channel is received. For a fault which is detected by relays at both remote terminals,AND 55 logic will not be satisfied, then channel (CR) will be performed via the logic whichallows pilot tripping (Figure 2-22, OR 21).


36

2.5.6 Weakfeed Trip Application

a. Block/Weakfeed

Special logic for a weakfeed terminal is not required for Blocking systems since Blockingsystems requires no permissive trip signal from the remote end, even though the remoteend is a weakfeed terminal. The strong end has no problem tripping for an internal fault.The weak end is usually assumed either as a “no feed” source, for which it does not needto trip on an internal fault, or it can pilot trip sequentially.

NOTE: For the case of “OS Block” is set to YES, Weakfeed should be set to YES if thisterminal can become a weak terminal (e.g. certain system configurations). Referto Figure 2-24, logic AND 41B and OR 41C.

b. PUTT/Weakfeed

The logic for a weakfeed terminal is not required for the PUTT system. Because the PUTTsystem uses underreaching relay(s) only for pilot trip keying, it is not necessary to applyweakfeed logic.

c. POTT/ Weakfeed

For POTT and unblocking schemes, at the weak source terminal, the Zone-3Ø /Z3G dis-tance relays should be set for reverse-looking, and the undervoltage units (LVA, LVB, LVC)should be used. The basic operating principle of the weakfeed trip logic for the POTT andsimplified unblocking scheme is as follows:

1) Echo key for trip permission (Figure 2-30)

On internal faults, the strong terminal(s) send the permissive (or unblocking) frequency sig-nal to the weak terminal, and the strong terminal(s) pilot trip logic will trip, once echo trippermission is received from the weak terminal. The pilot trip relay(s) at the weak terminalcannot operate since there is insufficient fault energy, and does not perform the normal key-ing function. With one weakfeed condition, when the weak end receives a permissive (orunblocking) signal, the output from the receiver operates the echo key logic via AND 65A,providing both pilot relay (from OR 40) and reverse logic (from REVERSE BLOCK LOGIC)have not operated and if system disturbance is detected (DV orDI). Output of AND 65A willkey the weak terminal transmitter to the permissive (or unblocking) frequency via OR 18,AND 35. On weak end reverse external fault, the strong source terminal(s) send the per-missive (or unblocking) frequency signal to the weak end, and the strong source terminal(s)pilot trip relay(s) wait to receive the echo trip permission from the weak end. However, atthe weak end, the echo key logic AND 65A will not operate, because of the REVERSEBLOCK LOGIC operation. Both the strong/weak terminals will not trip on this external fault.

2) Weak end trip on internal fault (Figure 2-30)

The output of AND 65A (echo keying) together with no output from OR 40 (pilot trip relays),no output from the REVERSE BLOCK LOGIC and with output from OR 44 (low voltage con-dition) will satisfy AND 66. Weakfeed trip (a high speed trip) will occur after 50 ms via OR2 (Figure 2-5). The time delay is for coordination because the voltage trip units are non-di-rectional.

2.5.6.1 Weakfeed System Application

For weakfeed applications, an inherent part of the logic requires reverse fault detection; Zone-3Ø/Zone-3 G and RDOG, which are a part of the REVERSE BLOCK LOGIC, supply this require-ment.

40-386.1

37

2.5.7 Reclose Block on Breaker Failure Squelch

For a pilot system, the BFI signal can be used to stop (for a blocking system) or start (for per-missive schemes) the carrier channel and allow the remote terminal to trip should the localbreaker fail to trip. The problem is how to inhibit the remote terminal from reclosing.

REL301/302 solves this problem by the with the RemBF RB squelch logic in the reclosing initi-ation logic. The logic, as shown in Figure 2-18, includes AND 61A and a 132/0 millisecond tim-er.

If the “RemBF RB” is set to “Yes” the logic will initiate reclose block (RB) 132 ms after the faultis detected by DV or DI, assuming the pilot is enabled and the TRSL signal is received on anypilot trip operation.

2. 6. PROGRAMMABLE CONTACT OUTPUTS

Most of the functions described in this section can be directed (single or combined) to the pro-grammable contact outputs. Refer to Section 4.10 for further details.


38

9651A57Sub 3

Figure 2-1: REL301/302 Characteristics/R-X Diagram

9654A13Sub 2

Figure 2-2: Mho Characteristic for Phase-to-Ground Faults

40-386.1

39

9654A14Sub 1

Sub 1

9654A15

Figure 2-3: Mho Characteristics for Three-Phase Faults (No Load Flow)

Figure 2-4: Mho Characteristics for Phase-to-Phase and Two Phase-to-Ground Faults (No Load Flow)


40

AND

ANDINPUTSA

BOUTPUT

ìíî

INPUTSOUTPUT

A B00II

0I0I

000I

A B

ELECTROMECHANICALCONTACT EQUIVALENT

SIGNAL ON ALL INPUTS REQUIRED TO PROVIDE AN OUTPUT

Notes: I – Active state of a signal (may be defined as positive or negative voltage or current)

0 – Inactive state of a signal (reference)

– Can have more than two (2) inputs

ORINPUTSA

BOUTPUT

ìíî

INPUTSOUTPUT

A B00II

0I0I

0III

ELECTROMECHANICALCONTACT EQUIVALENT

SIGNAL INPUT WILL PRODUCE AN OUTPUTALL INPUTS PRODUCE AN OUTPUT

A

B

=

=

= =

=

INCLUSIVE OR

INPUTS OUTPUT

0

I

I

0

NEGATION (NOT)

INPUT

INPUT

OUTPUT

OUTPUTOR

ABSENCE OF INPUT SIGNAL PRODUCES OUTPUT

TIMERS

INPUT OUTPUTTPTD

Input changes to Active State “1” -Output changes to Active State AfterTime Delay “On Pickup” (TP)

Input Changes to Inactive State “0”(Only After Having Been Active) - Output Changes to Inactive State AfterTime Delay “On Dropout”

Figure 2-5a: Logic Drawing Symbols

40-386.1

41

9657A49Sub 2

9657A50Sub 3

Figure 2-5b: Zone-1 Trip Logic

Figure 2-6: Zone-2 Trip Logic


42

1503B49Sub 2

9662A64Sub 1

Figure 2-7: Zone-3 Trip Logic

Figure 2-8: Zone-1 Extension Scheme

40-386.1

43

Figure 2-9: Inverse Time Overcurrent Ground Backup Logic

Figure 2-10: Loss-of-Potential Logic

9665A63* Sub 1

9665A64* Sub 1

* Denotes Change


44

Figure 2-11: Loss-of-Potential Logic (System Diagram)

Figure 2-12: Loss of Current Monitoring Logic

9654A18Sub 1

Sub 29657A54

40-386.1

45

Figure 2-13: Overcurrent Supervision

Figure 2-14: Instantaneous Overcurrent Highset Trip Logic

9662A66Sub 1

9665A65

* Sub 1

* Denotes Change


46

Figure 2-15a: REL301/302 Close-Into-Fault Trip (CIFT) Logic

Figure 2-15b: Special Application for CIF Logic with Time Delay Pickup

Figure 2-16: Unequal-Pole-Closing/Load Pickup Trip Logic & Reverse Block (TBM) Logic

9657A55Sub 3

9661A32Sub 2

9657A56Sub 2

40-386.1

47

9657A59

Sub 2

Figure 2-17: Load Loss Accelerated Trip Logic

Figure 2-18a: Reclosing Initiation Logic1503B51Sub 3

Figure 2-18b: Out-of-Step Block Logic (Blinder Characteristics)

9654A25Sub 1


48

9657A63Sub 4

Figure 2-20: REL302 POTT/Unblocking, PUTT and Blocking Pilot Relay

1503B50Sub 2

Figure 2-19: Out-of-Step Block Logic

40-386.1

49

9662A67Sub 2

1503B52Sub 3

Figure 2-21: REL302 POTT/Unblocking and PUTT Pilot Trip Logic

Figure 2-22: REL302 Channel Sending/Receiving Logic in POTT/Unblocking Schemes


50

9657A62Sub 2

Figure 2-23: REL302 Channel Sending /Receiving Logic in PUTT Scheme

Figure 2-24: REL302 Blocking System Logic

* Denotes Change

1506B53* Sub 1

40-386.1

51

9654A17Sub 1

Figure 2-25: Power Reversal on POTT/Unblocking Schemes

Figure 2-26: Unequal Pole Closing on Fault

9654A29Sub 1


52

9662A68Sub 1

9657A65Sub 3

FDOG TRIP

Figure 2-27: REL302 Pilot Ground Trip Supplemented by FDOG

Figure 2-28: REL302 Additional Logic for POTT/Unblocking Schemes on 3-Terminal Line Application

40-386.1

53

9662A69

Sub 1

Figure 2-29: REL302 Additional Logic for PUTT Scheme on 3-Terminal Line Application

Figure 2-30: REL302 Weakfeed Application

* Denotes Change

1503B54

*Sub 4


54

1503

B55

Sub

3

Fig

ure

2-31

: R

EL3

02 R

ever

sibl

e Z

one-

3 P

hase

and

Gro

und

(Rev

erse

Blo

ck L

ogic

)

I.L. 40-386.1

55

3.1. MEASUREMENT UNITS AND SETTING RANGES

DISTANCE MEASUREMENTS

• Three variable mho phase-to-ground units and one variable mho phase-to-phase impedanceunit per zone. Three Zones Phase and Ground Distance (Zone-1, 2, 3):

0.01 - 50 ohms in 0.01 ohm steps for 5 A (ct type)0.05 - 250 ohms in 0.05 ohm steps for 1 A (ct type)Any Zone (phase or ground distance) can be disabled

• Zone Timers – Separate timers for phase and ground:

Zone-1 (0 to 15 cycles in 1 cycle steps)Zone-2 (0.10 to 2.99 seconds in 0.01 second steps, Blocked of Torque Control Overcurrent)Zone-3 (0.10 to 9.99 seconds in 0.01 second steps, Blocked)Forward Directional Ground Timer (FDOGTime) (0 to 15 cycles in 1 cycle steps, Blocked)

OVERCURRENT MEASUREMENTS

• One ground directional (

“Inst. G”

)

1

and one phase directional (

“Inst. Ø”

) high-set overcur-rent setting for (I

AH

, I

BH

, I

CH

, I

OH

):

2.0 - 150 in 0.5 A steps for 5 A (ct type)0.4 - 30 in 0.1 A steps for 1 A (ct type)

• Three-phase non-directional overcurrent units (I

AL

, I

BL

, I

CL

) for Load Loss Trip and Close-IntoFault Trip with one setting (

“Low IØ”

).

• One ground overcurrent unit (

“3I0s”

) for Loss Of Current monitoring.

• Three non-directional medium set overcurrent units (IA

M

, I

BM

, I

CM

) for phase distance super-vision with one setting (

“IM”

).

• One non-directional medium set ground overcurrent unit (I

0M

) for ground distance supervi-sion with one setting (

“3I0m”

).

0.5 - 10 in 0.1 A steps for 5 A (ct type)0.1 - 2 in 0.02 A steps for 1 A (ct type)

• Three inverse time overcurrent phase units with CO type characteristics (see

Figures 2-32

through

2-38

) for Zone-2 phase torque control, time delay:

Pickup (0.5 - 10.0) in 0.1 A steps for 5 A (ct type).Choice of 7 time-curve families (CO-2, 5, 6, 7, 8, 9, 11 Characteristics), 63 curves per familywith instantaneous or time delay reset.

(Pickup (0.1 - 2.0) in 0.02 A steps for 1 A (ct type).)

• One inverse time overcurrent ground unit with CO characteristics (see

Figures 2-32

through

2-38

) for Zone-2 ground torque control, time delay:

Pickup (0.5 - 10.0) in 0.1 A steps for 5 A (ct type).Choice of 7 time-curve families (CO-2, 5, 6, 7, 9, 11 Characteristics), 63 curves per familywith instantaneous or time delay reset.


1. Bold type in quotation marks indicates LCD display quantities

Section 3. SETTING CALCULATIONS


56

• One inverse overcurrent ground unit with CO characteristics (see

Figures 2-32

through

2-38

) for ground backup:

Pickup (0.5 - 4.0) in 0.1 A steps for 5 A (ct type).Choice of 7 time-curve families (CO-2, 5, 6, 7, 8, 9, 11 Characteristics), 63 curves per familywith instantaneous or time delay reset. Set for directional or non-directional operation.


• One forward set instantaneous directional overcurrent ground unit. (REL 302 only, Pilot-highresistance ground faults, supervised by I

OM

).)

• One reverse set instantaneous directional overcurrent ground unit. (REL 302 only, CarrierStart, Weakfeed and Transient Block Logic, supervised by I

OS

.)

UNDERVOLTAGE MEASUREMENTS (“Low V”)

• Three under-voltage units (L

VA

, L

VB

, L

VC

) for Close-Into-Fault and Weakfeed Trip (REL 302only) supervision with one setting

“Low V”

.

40 to 60 Vrms in 1 - Volt steps.

OHMS PER UNIT DISTANCE (“X / Dist”)

• For fault locator measurement

0.300 - 1.500 in 0.001 Ohms per Distance Unit (Kilometers or Miles) in primary ohms.

OUT-OF-STEP BLOCK (“OS Block”)

• OUT-OF-STEP BLOCK Override Timer (

“OSOT”

)400 - 4000 ms in 16 ms steps

• OUT-OF-STEP BLOCK Inner Blinder (

“OS Inner”

)1.0 - 15.0 Ohms in 0.1 Ohm steps

NOTE: The inner blinder (RT) is a required setting since it is used as a load re-striction blinder even when OUT-OF-STEP BLOCK is not used.

• OUT-OF-STEP BLOCK Outer Blinder (

“OS Outer”

)3.0 - 15.0 Ohms in 0.1 Ohm steps

3.2. CALCULATION OF REL 301/302 SETTINGS

The following REL 301/302 setting calculations correspond to the setting categories in the In-stallation Section (4). Assume that the protected line has the following data:

• 18.27 miles

• Line reactance 0.8 ohms/mile (primary ohms)

• 69 kV, 60 cycles

• Positive and negative sequence impedances:

ZIL (Pri) = Z2L (Pri) = 15

Ð

77

o

ohms

• Zero sequence impedance:

Z0L (Pri) = 50

Ð

73

o

ohms

I.L. 40-386.1

57

• Current Transformer Ratio: (ct Ratio)RC = 1200/5 = 240 (set ct ratio = 240)

• Voltage Transformer Ratio: (vt Ratio)

RV = 600/1 = 600 (set vt ratio = 600)

Relay secondary ohmic impedances are:Z = Z

pri

x R

C

/R

V

Z1L = Z2L = 15

Ð

77˚ X 240 ____ 600

= 6

Ð

77˚ ohms

Z

0L

= 50

Ð

73

°

x 240/600 = 20

Ð

73

°

ohms

3.2.1 Ratio of Zero and Positive Sequence Impedances (ZR)

Z

0L

/Z

1L

= 20/6 = 3.33

Then REL 301/302 will automatically calculate the zero sequence current compensation factor(k

0

) by using the value of

“Z0L/Z1L”

,

“Ang Pos.”, “Ang Zero”

and reference to equation 1 in

Section 2.2.1

i.e.,

NOTE: The setting range of ZOL/ZIL has been expanded from 0.1 - 7.0 to 0.1 - 10 in 0.1steps. Also the setting ranges of Ang Pos. (Positive sequence line impedanceangle) and Ang Zero (Zero sequence line impedance angle) have been expand-ed from 40

°

-90

°

to 10

°

-90

°

as well. These changes were made to accommodatea wide variety of system components and configurations. However, the selec-tion of each setting has to be carefully considered if the maximum fault currentis 200 Amperes (secondary or above).

If the maximum fault current is 200 Amperes (secondary) the following restric-tions must be observed:

ZOL/ZIL less than or equal to 7.5The setting difference of |Ang Pos| - |Ang Zero| = 50 or less

If the maximum fault current is less than 200 Amperes (secondary) these re-strictions do not apply.

3.2.2 Zone-1 Distance Settings

A setting of 80% of the line impedance for Zone-1 reach is recommended, thus the Zone-1phase and ground reach should be

“Zone-1 Ø”

= 6 x 0.8 =

“4.8 OHMS”

and

“Zone-1 G”

= 6 x 0.8 =

“4.8 OHMS”

NOTE: “Zone-1 Ø” and “Zone-1 G” can be set for different values if the applicationrequires.

As stated above, start with a setting of 80% of the line impedance for the Zone-1 reach setting.Adjustment of the Zone-1 reach (line percentage) should be considered if any of the followingare true:

k0= Z0L Z1L–( )/Z1L ZOL Z1L¤( ) (AngZero AngPos– ) 1–Ð=


58

1) If the calculated Zone-1 impedance is 0.5 ohms (secondary) or less the line percentage,used for the calculation, should be 70-75%.

2) If the Source Impedance Ratio or SIR, (ratio of positive sequence source impedance topositive sequence line impedance) is in the range of 3-5 the line percentage, used for thecalculation, should be no more than 75%.

3) Circuit fault impedance angles in the range of 80 degrees produce dc time constant ofabout one cycle. One cycle time constants result in maximum overreach error of about16%. Hence the line percentage used should be no more than 70 - 75%. If the total faultimpedance angle is greater than 86 degrees, the dc time constant is greater than 2.3 cy-cles, and the overreach error is reduced to 10 percent or less. The same is true if the faultimpedance angle is less than 75 degrees. If system fault impedance angles are knownto be either above 86 degrees or below 75 degrees, the line percentage, used for theZone-1 calculation, can be increased by 5 percent.(All angles are based on 60 Hz sys-tems.) See figure 3-1.

NOTE: The fault impedance angle is fixed and is a measurement of the line char-acteristic, therefore the fault impedance angle is the angle of current look-ing from the relay into the fault.

4) If CCVT’s, of the low-capacitance type, (e.g. 1960’s vintage PCA-5 and PCA-8 designs)are in use, the line percentage, used for the Zone-1 calculation, should be 70-75%. Se-vere subsidence-transient related overreach has been noted in cases where low-capac-itance CCVT’s are used in “short line” applications. An alternative to reducing the Zone-1 setting, is to introduce a Zone-1 time delay (T1) of one or two cycles and using the 80percent Zone-1 reach calculation.


Generally, Zone-2 reach is set for 100% of the protected line plus 50% of the shortest adjacentline. If the shortest (or only) adjacent line primary impedance is 20 ohms, then the Zone-2 reachsetting would be:

“Zone-2 Ø”

= 6 + (20 x 0.5) x 240/600 = “

10 OHMS”

and

“Zone-2 G”

= 6 + (20 x 0.5) x 240/600 =

“10 OHMS”

NOTE: “Zone-2 Ø” and “Zone-2 G” can be set for different values if the applicationrequires.


Generally, Zone-3 reach is set for 100% of the protected line plus 100% of the longest adjacentline emanating from the remote bus, while accounting for the infeed from the same remote bus.

If the longest (or only) adjacent line from the remote bus is 25 ohms primary, and the infeed ef-fect may increase its impedance by 30%, then the Zone-3 reach setting should be:

“Zone-3 Ø”

= 6 + (25 x 1.3) x 240/600 =

“19 OHMS”

and

“Zone-3 G”

= 6 + (25 x 1.3) x 240/600 =

“19 OHMS”

I.L. 40-386.1

59

3.2.5 Overcurrent Settings

a. IL – Low-set Phase Overcurrent. The low set phase overcurrent unit is used for supervisingthe load-loss-trip and close into fault functions. It should be set higher than the line chargingcurrent and below the minimum load current.

NOTE: It should be set above the maximum tapped load current if applicable.

Assume that the line charging current is negligible for this line section and the minimumload current is 2.0 Amps secondary, then the low set phase overcurrent unit setting shouldbe:

“Low IØ”

=

“1 Amps”

b. IM – Medium-set Phase Overcurrent. The medium set phase overcurrent unit is used forsupervising the out of step blocking function and all phase distance tripping functions. Carein selecting the medium set phase overcurrent setting (

“IM”

) must be exercised to preventlimiting the Zone-3 distance reach. Traditionally,

“IM”

is set higher than load current when-ever possible.

In general, the criteria for setting medium set phase overcurrent is 1.13 X Maximum load cur-rent. Assume maximum load current is 4.0 amps secondary then:

“IM”

= 4.0 Amps X 1.13 =

“4.5 Amps”

(approximately)

The setting should be reviewed to assure it does not limit the reach of zone-3.

c. IOS – Low-set Ground Overcurrent. The low-set ground overcurrent unit is used for super-vising the reverse directional overcurrent ground unit (RDOG). It should be set as sensitiveas possible. A setting of 0.5 amperes is recommended:

“3I0s”

=

“0.5 Amps”

d. IOM – Medium-set Ground Overcurrent. The medium set ground overcurrent unit is usedfor supervising all ground distance units, the forward directional overcurrent ground unit(FDOG). Generally, it is recommended to be set 2 times the 3I0s setting.

“3I0m”

= 2 x

“3I0s”

=

“1.0 Amps”

e. ITP – High-set Phase Overcurrent / ITG High-set Ground Overcurrent. The directional highset overcurrent phase and ground units,

“Inst. Ø”

and

“Inst. G”

are used for direct trippingfunctions. The general setting criterion for the instantaneous direct trip unit is:

The unit should be set higher than 1.15 times the maximum fault on the remote bus, wherethe factor of 1.15 is to allow for the transient overreach. For this example, assume that themaximum load is not higher than the maximum forward end zone fault current, and themaximum phase and ground fault currents on the remote bus are 20 and 24 amperes, re-spectively, then the settings of the high-set phase (ITP) and the high-set ground (ITG)should be:

“Inst. Ø”

= 20 x 1.15 = “23 Amps”

“Inst. G” = 24 x 1.15 = “27.6 Amps”


60

3.2.6 Out-of-Step Block (“OS Block”) Blinder Settings (“OS Inner” and “OS Outer”)

The requirements for setting the blinder units are:

• Inner blinder must be set to accommodate maximum fault resistance for internal 3-phasefault

• Inner blinder should not operate on severe stable swings

• Outer blinder must have adequate separation from inner blinder for fastest out-of-step swingto be acknowledged as an out-of-step condition

• Outer blinder must not operate on load

a. Setting the Inner Blinder

If the out of step blocking (OSB) is used to supervise tripping of the 3Ø unit on heavy loadcurrent, the inner blinder 21BI must be set sufficiently far apart to accommodate the maxi-mum fault arc resistance. A reasonable approximation of arc resistance at fault inception is400 volts per foot. If a maximum ratio of “line voltage per spacing” is 10,000 volts/ft. for ahigh voltage transmission line, and if a minimum internal 3-phase fault current is calculatedas:

Imin. = [E / 1.73(ZA+ZL)]

where ZA is maximum equivalent source impedance, ZL is line impedance and E is line-to-line voltage.

then Rmax = 400 x FT / Imin.

= 400 x 1.73(ZA+ZL)/10000

= 0.0693 (ZA+ZL)

Adding a 50% margin to cover the inaccuracies of this expression:

Rmax. = 0.104(ZA+ZL) primary ohms

RS = 0.104(ZA+ZL)RC/RV secondary ohms

Set inner blinder to:

“OS Inner” = RT = RS x COS (90o - PANG) (1)

This is the minimum permissible inner blinder setting when it is used to provide a restrictedtrip area for a distance relay.

Another criterion that may be considered is based upon the rule of thumb that stable swingswill not involve an angular separation between generator voltages in excess of 120o. Thiswould give an approximate maximum of:

“OS Inner” = (ZA+ZL+ZB)/ (2x1.73) (2)

= 0.288(ZA+ZL+ZB) primary ohms

“OS Inner” = 0.288(ZA+ZL+ZB)RC/RV secondary ohms

where ZB is the equivalent maximum source impedance at the end of the line away from ZA.

An inner blinder setting between the extremes of equations (1) and (2) may be used. Thisprovides operation for any 3-phase fault with arc resistance, and restraint for any stable

I.L. 40-386.1

61

swing. Except in those cases where very fast out-of-step swings are expected, the largersetting can be used.

It will usually be possible to use the minimum inner blinder setting of 1.5 ohms.

b. Setting the Outer Blinder

For slow out-of-step swings, a reasonably close placement of outer to inner blinder charac-teristic is possible. The separation must, however, be based on the fastest out-of-step swingexpected. A 50 ms interval is inherent in the out-of-step sensing logic, and the outer blindermust operate 50 ms or more ahead of the inner blinder.

Since the rate of change of the ohmic value manifested to the blinder elements is depen-dent upon accelerating power and system WR2, it is impossible to generalize. However,based on an inertia constant (H) equal to 3, and the severe assumption of full load rejection,a machine will experience (assuming a uniform acceleration) an angular change in positionof no more than 20o per cycle on the first half slip cycle.

If the inner blinder were set for (0.144 ZT), and the very severe 20o per cycle swing ratewere used, the outer blinder should be set for approximately:

“OS Outer” = 0.5 ZT primary ohms (3)

where

ZT = ZA + ZB + ZL

This is the minimum setting of the outer blinder for a 20o per cycle swing rate.

3.2.7 Timer Settings (Definite Time Setting)

a. Zone-1 has an adjustable definite time timer, “T1 Timer” which is normally set to “0 cy-cles”. The zone-1 timer could be used to delay tripping when coordinating with a sloweroperating device at a remote terminal. The timer also can be used to delay tripping for co-ordination of relay systems at the same terminal when the coordination is with a slowerdevice.

b. Zone-2 timers, for phase and ground, have two choices of time delay type. Choices are def-inite time (“T2Ø Type” and “T2G Type” set to “Definite Time”) or zone-2 torquecontrolled, time delay overcurrent (“T2Ø Type” and “T2G Type” set to “Torque Control”).Torque control overcurrent time delays will be discussed in Section 3.2.8.

Zone-2 definite time delay (“T2Ø Time” and “T2G Time”) settings should be coordinatedwith the Zone-1 and other high-speed trip units on the adjacent line terminals. CoordinationTime Interval of 0.3 to 0.5 seconds is recommended. For example, if “T2Ø Time” and“T2G Time” of 0.4 seconds is used, then the phase and ground Zone-2 timers should beset as follows:

“T2Ø Time” = 0.4 seconds and“T2G Time” = 0.4 seconds

NOTE: T2Ø Time and T2G Time are separate timers; they can have different timesettings if the application requires.


62

c. Zone-3 timers (“T3Ø Time” and “T3G Time”) settings would be similar to the above. Forexample, if T3 of 0.8 seconds is required, then the phase and ground Zone-3 timers shouldbe set as follows:

“T3Ø Time” = 0.8 seconds and“T3G Time” = 0.8 seconds

NOTE: T3Ø Time and T3G Time are separate timers; they can have different timesettings if the application requires.

d. For Out-of-Step Block (“OS Block”), if applied, the Out-of-Step Block Override Timer Set-ting (“OSOT”) is determined by the power system operation. Its range is 400 to 4000 ms,in 16 ms steps.

e. For the REL 302 blocking system only, the channel coordination timer setting (“Blk Time”)is based on the following application criteria:

“Blk Time” > (Slowest remote carrier start time + channel time + margin) - (the fastest local21P/21NP pickup time)

Where channel time includes the transmitter and receiver times, and the times which occurbetween these devices, e.g., wave propagation, interfacing relays, etc.

For REL 302: fastest 21P/21NP pickup time = 14 msslowest carrier start time = 4 mssuggested margin time = 2 ms

For example, the REL 302 channel coordination timer should be determined as shown be-low, if the channel time is 3 ms.

“Blk Time” = (4 + 3 + 2) - 14 = -5

i.e., set “Blk Time” = 0

3.2.8 Timer Settings (Torque Control Overcurrent)

Zone-2 timers, for phase and ground, can be set for a timed overcurrent delays. Zone-2 torquecontrolled, time delay overcurrent (“T2Ø Type” and “T2G Type” set to “Torque Control”) pro-vides access to seven sets of overcurrent curves which are similar to ABB CO curves. Threesettings “T2Ø CV”, “T2Ø PkUp” and “T2Ø TC” must be determined to apply phase torquecontrolled overcurrent protection. Similar settings are required for the ground torque controlledovercurrent protection.

a. “T2Ø CV” - Zone-2 phase overcurrent curve family setting. Seven sets (families) of COtype overcurrent curves are provided and shown in Figures 2-32 through 2-38. As with anyovercurrent function, curve family selection is based on the application and coordinationwith other overcurrent devices. Setting the family setting is by choosing CO-2, C0-5, CO-6,CO-7, C0-8, CO-9 or CO-11. Each of the curve sets offers a choice of reset characteristicwhich is explained below.

b. “T2Ø PkUp” - Zone-2 phase overcurrent pickup setting. In general, the pickup setting isset above maximum load current and below maximum phase fault current. For maximumsensitivity, the pickup should be set as close to maximum load current as possible. Pickupsetting range is 0.50 - 10.00 Amps.

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c. “T2Ø TC” - Zone-2 phase overcurrent curve selection setting. This setting can also be re-ferred to as the time dial setting. As shown in Figures 2-32 through 2-38, “T2Ø TC” issettable in steps of one from 1 to 63. As with any overcurrent function, curve time dial isbased on the application and coordination with other overcurrent devices.

Similarly, three settings “T2G CV”, “T2G PkUp”, “T2G TC” must be determined to applyground, torque controlled overcurrent protection. Similar to any overcurrent application, thesame criteria as in a, b, and c above are used to select appropriate settings for ground, torquecontrolled overcurrent protection.

The following equations can be used to calculate the trip time for all phase and ground backupcurves

T (sec) = (for IP >1.5 x “T2Ø PkUp”)

T (sec) = (for 3I0 >1.5 x “T2G PkUp”)

T (sec) = (for 1< 3IP < 1.5 x “T2Ø PkUp”)

T (sec) = (for 1 < 3I0 < 1.5 x“T2G PkUp”)

Where:

IPF = Applied fault current3I0F = Applied zero sequence fault current

“T2Ø PkUp” = Phase pickup current setting (0.50 to 10.0 Amps)

“T2Ø TC” = Phase time dial curve setting (1 to 63)

“T2G PkUp” = Ground pickup current setting (0.50 to 10.0 Amps)

“T2G TC” = Ground time dial curve setting (1 to 63)

T0, K, C, P and R are constants, and are shown in Table 3-1

Torque control of the overcurrent functions is by way of the operation of zone-2 phase and/orground distance logic operating. When a zone-2 distance decision is made, the overcurrent log-ic is enabled and the curve timing begins. Operation time of the zone-2 distance (phase orground) decision must be added to the overcurrent trip time calculated above. Since zone-2 op-erate time is approximately 22 milliseconds, add 22 milliseconds to the times calculated for totaltrip time.

T0K

IP C–( )P------------------------+

T2f TC24 000,---------------------´

T0K

3I0 C–( )P---------------------------+

T2GTC24 000,---------------------´

RIP 1–( )

-------------------T2f TC24 000,---------------------´

R3I0 1–( )

----------------------GBT Curve

24 000,--------------------------------´

IPIPF

T2Æ PkUp------------------------------= 3I0

3IoFT2G PkUp-----------------------------=


64

REL 301/302 offers two reset characteristics for the torque control overcurrent functions, instan-taneous or time delayed. Instantaneous reset, as the name implies, means reset with no inten-tional time delay. Time delay reset function is a linear characteristic shown in Figure 3-9 and isintended to replicate the reset characteristics of electromechanical overcurrent relays.

3.3. REQUIRED SETTINGS APPLICATION

The following settings are determined by the application. They do not require calculation.

3.3.1 Oscillographic Data (“OSC Data”) Capture Setting

The OSC setting is for selecting one of the 4 choices, “TRIP”, “Z2TR”, “Z2Z3” or “DIDV”, toinitiate the oscillographic data taken, where:

“TRIP” – data taken only if trip action occurs.

“Z2TR” – data taken if Zone-2 units pick up, or any trip action occurs.

“Z2Z3” – data taken if Zone-2 or Zone-3 units pick up, or any trip action occurs.

“DIDV” – data taken if DI, DV, Zone-2 or Zone-3 units pick up, or any trip action occurs.

NOTE: The setting of “DIDV”, for OSC is not recommended since data will be col-lected for all disturbances including normal operations.

3.3.2 Fault Data (“Flt Data”) Capture Setting

Is for selecting one of the 3 ways “TRIP”, “Z2TR”, “Z2Z3” to initiate the fault data taken, where:

“TRIP” – to store fault data only if trip action occurs.

“Z2TR” – to store fault data if Zone-2 units pick up or any trip action occurs.

“Z2Z3” – to store fault data if Zone-2 or Zone-3 units pick up or any trip action occurs.

3.3.3 Current Transformer Ratio Setting (“CT Ratio”)

The “CT Ratio” is used for the fault distance calculation and load current monitoring, if it is se-lected to be displayed in primary amperes. It has no effect on the protective relaying system.

For this example, set “CT Ratio” = 240.

3.3.4 Voltage Transformer Ratio Setting (“VT Ratio”)

The “VT Ratio” is used for the fault distance calculation and system voltage monitoring, if it isselected to be displayed in primary volts. It has no effect on the protective relaying system.

For this example, set “VT Ratio” = 600.

3.3.5 Frequency Setting (“Freq.”)

Should be selected to match the power system operating frequency.

For this example, set “Freq.” = 60

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65

3.3.6 Current Transformer Type Setting (“CT Type”)

Provides the flexibility for 5 amp or 1 amp rated current transformer selection.

For this example, set “CT Type” = 5 since a 5 amp current transformer is used.

The setting of “CT Type” affects all the distance unit and overcurrent unit setting ranges. Theranges will be automatically changed as listed in Table 3-3.

3.3.7 Read Primary Setting (“Read Out”)

The “Read Out” should be set to “Primary Units” if all the monitoring ac voltages and currentsare selected to be displayed in primary KV and KA values, respectively. Select “SecondaryUnits” to view voltages and currents in relay or secondary values.

NOTE: When reading secondary units only one digit will read out after the deci-mal point. When reading primary units RP must be set to “yes”.

3.3.8 Ohms Per Unit Distance (“X / Dist”)

The line reactance setting “X / Dist” is the multiplier for fault distance calculation. It has a rangeof 0.3 to 1.5 ohms (primary) in 0.001 steps. In this example, the line reactance is 0.8 ohms/mile;set “X / Dist” = “0.8 Ohms”.

The fault distance calculation is as follows:

Where ZS is the secondary impedance magnitude, and FANG is the fault angle.

3.3.9 Distance Type (“DistUnit”) Setting

Distance type (“DistUnit”) has a selection of “MILE” or “KM”. It should be selected to matchwith the setting of “X / Dist”. For this example, select “DistUnit” = “MILE”.

3.3.10 Reclosing Mode (“RI Type”) Setting

“RI Type” is for selecting the reclosing mode. It has four setting positions, “No RI”, “ØG RI”,“ØØ,ØG RI', “3Ø, ØØ, ØØG, ØG RI”. Refer to the guidelines for reclosing mode programmingfor the “RI Type” setting selection in Section 2.4.14.

3.3.11 Reclose Initiation Settings

“Fast RI”, “Zone-2 RI” and “Zone-3 RI” provide the selectivity for High speed tripping units,Zone-2 and Zone-3 reclosing initiation, respectively. See Section 2.4.14 for details

3.3.12 Remote Breaker Failure, Reclose Block (“RemBF RB”)

For a pilot system (REL 302 only), set “RemBF RB” to “Yes” if reclose block output to preventthe remote breaker from reclosing for local breaker.

Flt DistVT RatioCT Ratio--------------------------

ZS FANGÐsin´

X / Dist--------------------------------------------´=


66

3.3.13 Remote Pilot Control (“Pilot”) Setting

“Pilot” set to “Yes” combines with the signal of PLT ENA2 (external 85CO input) and controlsthe operation of pilot logic tripping and reclosing initiation. The absence of either signal will dis-able the pilot system logic.

The “Pilot” setting can be set either locally from the front panel, or via the communication in-terface.

3.3.14 System Type Selection (“SystType”)

“SystType” selects the desired relaying system for the application. REL 301 has two settingchoices: “Non Pilot” and “Zone-1 Extension”. REL 302 has five setting choices: “Non Pilot”,“Zone-1 Extension”, “POTT” (permissive overreach transfer trip), “PUTT” (permissiveunderreach transfer trip) and “Blocking” (directional comparison blocking).

3.3.15 For The Pilot REL 302 Only

a. “3-Term.”, 3- terminal line configuration setting, should be set to “Yes” for all three terminalline applications.

b. “Weakfeed” (weakfeed terminal logic enable) selection should be set to “Yes” for all weak-feed terminal applications.

c. For applications of “POTT” or “Blocking”, systems, the transient block logic is always au-tomatically enabled and is initiated by the reverse looking units. Set “Zone-3” to “ReverseDir.” and “Zone-3 Ø” and “Zone-3 G” should be set to 100% of the reverse lineimpedance.

d. The “FDOGTime” (FDOG trip delay timer) can be set from “0” to “15 cycles” or“Blocked” as desired. It is recommended to set “FDOGTime” to 3 cycles or longer. Referto Section 2.5.2 for the detailed information.

3.3.16 Distance/Overcurrent

Individual distance and overcurrent logic can be disabled, if required by the application by set-ting the unit to “Disabled”:

a. List of units which can be disabled:

“Pilot Ø”, “Pilot G”, “Zone-1 Ø”, “Zone-1 G”, “Zone-2 Ø”, “Zone-2 G”, “Zone-3 Ø”,“Zone-3 G”, “Inst. Ø”, “Inst. G” and “GB Type”.

b. Procedure to disable the unit:

Switch REL 301/302 to the setting mode (see Section 4.4.2), scrolling the function field tothe desired function. Then set the unit to “Disabled”.

3.3.17 Step Distance Timers

a. “T1 Timer” can be set from 0-15 cycle delay and cannot be disabled.

2. Bold type, with small capital letters, indicates an input e.g. RESET push-button or voltage inputs.

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67

b. The “T2Ø Type”, “T2G Type”, “T3Ø Time” and/or “T3G Time” timer functions can be dis-abled, if desired, by setting the timer to “Blocked”. Timers set to “Blocked”, block outputfrom the associated trip logic. For example, if “T3Ø Time” is set to “Blocked” Zone- 3 logicwill not produce a trip output.

3.3.18 Zone-3 Direction Setting (“Zone-3”)

“Zone-3 Ø” and “Zone-3 G” can be selected to be forward-looking or reverse-looking by set-ting the “Zone-3” (Zone-3 forward or reverse setting) to “Forward Dir.” or “Reverse Dir.”

3.3.19 Positive Sequence Impedance Line Angle (“Ang Pos.”)3

Set the Positive Sequence Line Impedance Angle setting “Ang Pos.”, to the value of the posi-tive sequence line impedance angle. From the example data (Section 3.2), the setting wouldbe “Ang Pos.” = “77o”.

3.3.20 Zero Sequence Impedance Angle (“Ang Zero”)3

Set the Zero Sequence Impedance Angle setting (“Ang Zero”) to the value of the zero se-quence line impedance angle. From the example data (Section 3.2), the setting would be “AngZero” = “73o”.

3.3.21 Zero Sequence/Positive Sequence Ratio (“ZOL/Z1L”)4

Set the “ZOL/Z1L” value based on the absolute value of the ratio of the line impedances. Fromthe example data (Section 3.2), the setting would be “ZOL/Z1L” = “3.3”.

3.3.22 Low Voltage Settings (“Low V”)

The low voltage units are used to supervise close into fault logic and weakfeed trip logic (REL302 only). “Low V” should normally be set to “40 Volts” unless a higher setting is required formore sensitive applications.

3.3.23 Polarizing Settings

Settings for the directional ground overcurrent polarization is controlled by the setting of “DirType”. It has 3 selections:

“Zero Sequence” — Zero sequence voltage polarization.

“Negative Sequ.” — Negative sequence voltage polarization.

“Dual Polariz.” — Both zero sequence voltage and current polarization.

3.3.24 Overcurrent Ground Backup

The overcurrent ground backup function provides seven sets of curves, which are similar to theCO curves, for backing up the ground distance protection. Four settings “GB Type”, “GB Pick-up”, “GBT Curve” and “GB Dir.” must be determined for applying this function.

3. See application note under Section 3.2.14. See application note under Section 3.2.1


68

a. “GB Type” is the ground backup curve selection. Seven sets of familiar CO curves areprovided (C02,5,6,7,8,9 and 11), and are shown in Figures 2-32 through 2 -38. The selec-tion is based on the application and coordination time. A selection of “Disabled” preventsthe ground backup function from operating.

b. “GB Pickup” is the current level setting. The setting range is 0.5 to 4.0 amperes in 0.1steps. In general, the current level setting criteria is:

(IFmin /2) > “GB Pickup” > 2 x Max. Residual 3I0

where IFmin = Minimum ground fault current for a fault two buses away

For the best sensitivity, “GB Pickup” should be set at 0.5 amperes, this is normally ade-quate for most applications.

c. “GBT Curve” is the time delay setting of the ground backup function. As shown in Figures3-2 through 3-8, the “GBT Curve” is settable in steps of one from 1 to 63. As with any timedelay overcurrent function, the time delay setting must be coordinated with other overcur-rent devices.

d. “GB Dir.” is the setting for directional control selection. The ground backup function be-comes a forward-directional torque control overcurrent ground function if “GB Dir.” is set to“Yes”. If “GB Dir.”is set to “No”, the overcurrent ground backup function is non-directionaland will produce a trip output for faults in the forward and reverse directions.

The following equation can be used to calculate the trip time for all CO curves from CO-2through CO-1 :

T (sec) = (for 3I0 >1.5 x “GB Pickup”)

T (sec) = (for 1< 3I0 < 1.5 x “GB Pickup”)

Where 3I0 =

IF = Applied fault current

“GB Pickup” = Pickup setting

“GBT Curve” = Time curve dial setting (1 to 63).

T0, K, C, P and R are constants, and are shown in Table 3-1.

Taking the CO-8 curve set as an example (see Figure 2-36), assuming that the maximum3Io of unbalanced load is 0.2A, the minimum ground fault current for a fault two buses awayis 10A, and 0.7 seconds is required for coordination with current of 20 times the “GB Pick-up” setting, then the settings of the ground overcurrent backup function should be asshown below:

T0K

3I0 C–( )P---------------------------+

GBT Curve24 000,

--------------------------------´

R3I0 1–( )

----------------------GBT Curve

24 000,--------------------------------´

IFGB Pickup-------------------------------

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69

10/2 > “GB Pickup” > 2 x 0.2 set “GB Pickup” = 0.5

Choosing from the curves, in Figure 2-36, for 0.7 seconds at 20 times the “GB Pickup”setting, “GBT Curve” should be set to “24”. Set “GB Type” to “C0-8” and set “GB Dir”to “YES” if directional control is required.

REL 301/302 offers two reset characteristics for the ground backup overcurrent function,instantaneous or time delayed. Instantaneous reset, as the name implies, means reset withno intentional time delay. Time delay reset function is a linear characteristic shown in Fig-ure 3-9 and is intended to replicate the reset characteristics of electromechanical overcur-rent relays.

3.3.25 Close-Into-Fault Trip Setting (“CIF Trip”)

Set “CIF Trip” setting by selecting the value field “CIF Trip” if line side potential is used to sup-ply the relay. See Section 2.4.7 for special applications of close-into-fault logic.

3.3.26 Load Loss Trip Setting (“LL Trip”)

Set “LL Trip” to “YES”, FDOG or NO, where:

“YES” – “LL Trip” trip with Z2 supervision.

“FDOG” – “LL Trip” with both Z2 and FDOG supervision.

“NO” – “LL Trip” function is not used.

3.3.27 Loss of Potential Block Setting (“LOP Blk”)

Set “LOP Blk” to “YES”, if loss-of-potential block trip function is required.

3.3.28 Loss of Current Block Setting (“LOI Blk”)

Set “LOI Blk” to “YES”, if loss-of-current block trip function is required.

3.3.29 Trip Alarm Setting (“Trip Alm”)

Set “Trip Alm” to “Seal-in”, if trip alarm seal-in is required. The front panel, reset push-buttoncan be used to reset the sealed alarm.

3.3.30 Remote Setting (“Rem. Set”)

Set the “Rem. Set” to “Remote Allowed” if remote setting, via communications port, is re-quired.

3.3.31 Real-Time Clock Setting

With REL 301/302 in the “setting” mode, scroll the function field to “Set Time”, and change thevalue to “Yes”. Depress function push-button RAISE to display Year, Month, Day, Weekday,Hour, and Minute, and set the corresponding number via the value field. The REL 301/302 clockwill start at the time the enter button is pushed while the display is showing the minute value.


70

3.4. RECLOSE INITIATION MODE PROGRAMMING

3.4.1 For Non-pilot and Pilot Systems

1. Select “RI Type” = “No RI”; “ØG RI”; “ØØ, ØG RI”; or “3Ø, ØØ, ØØG, ØG” (See Table3-2)

2. Use one of the two (RI-1 or RI-2)5 output contacts for the reclosing initiation circuit

3. Select one or all of the “Fast RI”, “Zone-2 RI”, and/or “Zone-3 RI” to “Yes”, depending onthe application. (REL 302 set for Pilot System: For reclose initiation, following Pilot tripping,“Fast RI” should be set to either “Pilot” or “Pilot/Z1/Inst I”)

5. Bold italic type indicates an output e.g. LEDs or contact output

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Table 3-1: TRIP TIME CONSTANTS FOR CURVES

CURVE # T0 K C P R

C02 111.99 735.00 0.675 1 501

C05 8196.67 13768.94 1.13 1 22705

C06 784.52 671.01 1.19 1 1475

C07 524.84 3120.56 0.8 1 2491

C08 477.84 4122.08 1.27 1 9200

C09 310.01 2756.06 1.35 1 9342

C011 110 17640.00 0.5 2 8875

Table 3-2: RECLOSING INITIATION MODE PROGRAMMING

“RI Type” Type Of Fault Reclosing Initiation Mode

“No RI” All Faults No reclosing initiation

“ØG RI” ØG RI-1, RI-2 contacts close;All Other Faults no reclosing

“ØØ, ØG RI” ØG, ØØ RI-1, RI-2 contacts close;3Ø Faults no reclosing

“3Ø, ØØ, ØØG, ØG” All Faults RI-1, RI-2 contacts close

Table 3-3: CURRENT TRANSFORMER SETTINGS

REL 301/302 At CTYP = 5 At CTYP = 1

Z1P/Z1G/Z2P/Z2G

Z3P/Z3G/PLTP/PLTG

0.01 - 50.00, in 0.01 W steps 0.05 - 250, in 0.05 W steps

ITP/ITG 2.0 - 150.00, in 0.5 A steps 0.4 - 30.0, in 0.1 A steps

IL/IOS/IOM/IM 0.5 - 10.0, in 0.1 A steps 0.1 - 2.0, in 0.02 A steps

INS

TR

UC

TIO

N M

AN

UA

L R

EL

301/302

72

Figure 3-1: % Overreach Resulting from dc Offset Effect

5

0

-5

10

15

20

8786858483828180797877767574

% Overreach Resulting from DC Offset Effect On Sampling

Line Angle

%O

verr

each

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Figure 3-2: CO-2 Curve Characteristics

605879 REV 0


74


605882 REV 0

I.L. 40-386.1

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605881 REV 0


76


605880 REV 0

I.L. 40-386.1

77


605878 REV 0


78

Figure 3-7: CO-9 Curve Characteristics605877 REV 0

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Figure 3-8: CO-11 Curve Characteristics605876 REV 0


80

Figure 3-9: Overcurrent Reset Characteristics

95

90

85

80

75

70

65

60

55

50

45

40

35

30

25

20

15

10

5

00 3 6 12 18 24 30 36 42 48 54 63

CO-5

CO-8

CO-11

CO-9

CO-7

CO-6

CO-2

Typ

ical

To

tal R

eset

Tim

e (S

eco

nd

s)

Time Dial Position

Sub 19669A10

I.L. 40-386.1

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Section 4. INSTALLATION AND OPERATION

4. 1. SEPARATING THE INNER AND OUTER-CHASSIS

It is recommended that the user of this equipment become acquainted with the information inthese instructions before energizing the REL 301/302 and associated assemblies. Failure to ob-serve this precaution may result in damage to the equipment.

All integrated circuits used on the modules are sensitive to and can be damaged by the dis-charge of static electricity. Electrostatic discharge precautions should be observed when oper-ating or testing the REL 301/302.

! CAUTION

Use the following procedure when separating the inner chassis from the outerchassis; failure to observe this precaution can cause personal injury, undesiredtripping of outputs and component damage.

a. Unscrew the front cover knob and remove cover.

b. Open all FT switches completely.

! WARNING

Do Not Touch the outer contacts of any FT-10 switch; they may be energized.

c. Release frame latches by pushing the top and bottom latches inward towards the center ofthe relay.

d. The inner chassis removal lever is located on the left center (vertical mount) or on top cen-ter (horizontal mount) of the inner chassis. Push the lever towards the middle tab on theframe.

e. Slide out the inner chassis.

f. Reverse procedures above when replacing the inner chassis into the outer chassis.

4. 2. TEST PLUGS AND FT SWITCHES

Test Plugs are available as accessories (Section 1.6.6). They are inserted into the FT-10 switch-es for the purpose of System Function Tests.

4. 3. EXTERNAL WIRING

All electrical inputs/outputs are made through the back of the REL 301/302. Figure 4-1 illus-trates where the different input/output signals are located. The vertical REL 301/302 is used asa reference in the location column of the Connection Specification Chart (similarly for the hori-zontal REL 301/302).

Note: If the separate polarizing input (FT-12 and FT-13) is not used,a shorting jumper must be installed.


82

1. Contact rating information see

Section 1.6

CONNECTION SPECIFICATION CHART

Location Notes

ANALOG INPUTS

See Figure 4-2 Voltages and Currents

SIGNAL INPUTSNon-Pilot Connection

52a52bEXT RESET

Pilot Connection REL 302(Add FollowingConnections)

PLT ENARCVR1RCVR2

Reclosing/Sync-check

HOLDEXT.RIRECLOSE LOCKOUT

Terminals TB4-3 (+), TB4-4 (-)Terminals TB4-5 (+), TB4-6 (-)Terminals TB4-7 (+), TB4-8 (-)



52a only required for some reclosing applications.52b contact required for some logic functions.External Reset - resets LEDs and

erases

protection targets.

85CO input required for pilot logic operation.Channel 1 receiver input.Channel 2 receiver input 3-term.

Stops reclosing cycle.Begin (initiates) reclosing cycle.Drives reclosing cycle to lockout.

CONTACT OUTPUTSTrip Connection

TRIP A1TRIP A2

Terminals TB1-4, FT-6Terminals TB1-3, FT-7

Isolated TRIP 1, switched by FT-6Isolated Trip 2, switched by FT-7

Basic System Connections

OC1SYS TEST

BFI/RI ENA

RI-1RI-2RB1RB2OC3BFIA-1BFIA-2OC2OC4OC5/STOP GSAL-1AL-2

Terminals TB1-2, FT-8Terminal TB1-1

Breaker Failure Initiate/Reclose InitiateTerminals TB3-1, TB3-2Terminals TB3-3, TB3-4Terminals TB3-5, TB3-6Terminals TB3-7, TB3-8Terminals TB3-11, TB3-12Terminals TB3-13, TB3-14Terminals TB3-15, TB3-16Terminals TB3-17, TB3-18Terminals TB3-19, TB3-20Terminals TB3-21, TB3-22Terminals TB3-23, TB3-24Terminals TB3-15, TB3-26Terminals TB3-27, TB3-28

Trip rated

1

programmable contactJumper connected to FT-5, required to power BFI/I enable function.Enabled/Disabled by FT-5.*

Isolated Reclose Initiate, (FT-5*)Isolated Reclose Initiate, (FT-5*)Isolated Reclose Block, (FT-5*)Isolated Reclose Block, (FT-5*)Non-trip rated

1

programmable output contact.Isolated Breaker Failure Initiate, (FT-5*)Isolated Breaker Failure Initiate, (FT-5*)Non-trip rated

1

programmable output contact.Non-trip rated

1

programmable output contact.Non-trip rated

1

programmable output contact.General Start, closes for any disturbance detectionIsolated Failure AlarmIsolated Relay Trip Alarm

Pilot Connection(Add followingConnections)

SENDSTOP

Terminals TB3-9, TB3-10Terminals TB3-21, TB3-22

Pilot Channel Equipment StartPilot Channel Equipment Stop (Programmed Stop Function)

Reclosing/Sync-check

CLOSE-1CLOSE-2LOCKOUTFAIL RECLOSEIN PROGRESS

(Optional)

Terminals TB2-1, TB2-2Terminals TB2-3, TB2-4Terminals TB5-1, TB5-2Terminals TB5-3, TB5-4Terminals TB5-5, TB5-7

Isolated Close Contact #1Isolated Close Contact #2Alarm for Lockout StateProgrammable Output for Failed Reclose State/Sync StatusProgrammable Output for Reclose in Progress/Sync Status

CommunicationConnection

:See Sections 4.6 and 4.7

I.L. 40-386.1

83

LED Color Condition

PROTECTION LEDS

PROTECTION IN SERVICE Yellow ON– For Normal condition of dc power Successful self-check Self-test routinesOFF – Any of the above failed

PILOT Red Pilot TrippedZONE-1 Red Zone 1 TrippedZONE-2 Red Zone 2 TrippedZONE-3 Red Zone 3 TrippedAG Red AG FaultBG Red BG FaultCG Red CG FaultM

f

Red Multi-phase FaultOTHER Red Fault Generated by Overcurrent

Load Loss, orTrip Relays Testing

RECLOSING AND SYNCH-

(

OPTIONAL

)

CHECK RELATED LEDS

RECLOSING IN SERVICE Yellow ON – dc power ONLOCKOUT Yellow Reclosing Logic in Lockout StateFAILED RECLOSE Yellow Breaker associated with Recloser failed to recloseHBDL Yellow Bus is Live and Line is DeadHLDB Yellow Line is Live and Bus is DeadSYNCHRONISM Yellow Bus and Line Voltages in Synchronism

FRONT PANEL LED INDICATOR CHART

4. 4. FRONT PANEL MAN-MACHINE INTERFACE (MMI)

4.4.1 LED Indicators

The REL 301/302 comes with LEDs on the front panel. “IN SERVICE” LED should be on, allother indicators are off in normal conditions, but after a trip, the ones related to the trip blink. Ifa second trip occurs, the LEDs related to the latest fault double blink. See Section 5.1.1 for moredetails.

4.4.1.1 LEDs and Display Reset

The push-button labelled RESET is used to reset all the trip LEDs and send the display to themetering mode.

4.4.2 Display Module

The front panel operation provides a convenient means of checking and changing settings, andfor checking relay unit operations after a fault.

It consists of a 2-line 16-character/line LCD display, 4 push-buttons (SELECT, LOWER, RAISE,ENTER) and a switch. The latter selects the display of either the protection or the optional re-closer. It should always be in protection mode when no reclosing information is being viewed orduring re-initialization.

The front panel has different modes of operation, shown at the top right of the display. The 4push-buttons labeled SELECT, LOWER, RAISE, and ENTER, are used to interface with theREL 301/302 relay menu and settings.


84

4.4.2.1 Front Panel Operation

There are five different modes, described below:

MODE As Displayed

SETTINGS [SET]METERING [METER]LAST-FAULT [L-FLT]PREVIOUS-FAULT [P-FLT]TEST [TEST]

By keeping the SELECT push-button depressed, the list of modes is scrolled in the sequenceshown above, at a one second rate. For each selected mode, the corresponding functions canbe scanned (also every second) with the LOWER or RAISE push-buttons.

a. SETTING MODE

In this mode, functions and their values can be scrolled or changed. See

Table

4-1, forcomplete listing. The FUNCTION (shown on the top left of the display), can be scrolledby continuously depressing either the LOWER or RAISE push-button, depending on thedesired scrolling direction. The corresponding VALUE displayed on the second line can

be changed by pressing the ENTER push-button once. An underscore dash will thenflash alternatively between the first and last characters on the second line. At this point,

other values for the same function can be scrolled through by depressing the LOWERor RAISE push-button. When the desired value is reached, select it by pressing ENTERuntil VALUE UPDATED shows on the display. After the value is updated the systemthen returns to the function scroll state.

In order to restore the original value while in the middle of the scrolling values, pressSELECT instead of ENTER, the system returns to the function scroll state, without up-dating the setting. In the function scroll state, a jump to the next mode is performed bypressing SELECT.

b. METERING MODE

In this mode, all metered data is displayed. See

Table

4-2, page 4-18, for complete list-ing. This includes all phase currents and voltages with their angle referred to V

AG

,

conditions such as loss-of-potential, loss-of-current and out-of-step blocking and alsothe present time. Depending on the Read

Out setting, the currents and voltages areshown either in primary or secondary side units.

Set time No

SET

Set time SET

— No —

IA : 0.0A

METER

I.L. 40-386.1

85

To scroll through the metered data press the LOWER or RAISE push-buttons.

c. TARGET MODE (LAST-FAULT and PREVIOUS-FAULT)

REL 301/302 saves the 16 latest fault records. See

Table

4-3, for complete listing. TheL-FLT is the most recent fault, the P-FLT is the one prior to the L-FLT. These tworecords can only be viewed from the front panel. All other targets must be viewedthrough one of the remote communications interfaces.

They can be deleted by External Reset or through a remote communication interface.The front panel RESET push-button resets the LEDs and resets the display to the me-tering mode.

As soon as a fault event is detected, the most recent two sets of target data are avail-able for display. If the setting Flt Data is set to Trip, the L-Flt is the data associated withthe most recent trip event. If a single fault occurs, the fault related LEDs blink. If reclos-ing is applied and the system trips again, the original L-Flt information is transferred tothe P-Flt memory. The latest trip information is stored in the L-Flt memory and the L-Fltrelated LEDs double blink. If Flt Data is set to Zone 2, two events (Zone 2 pickup andtrip) will be stored. If Flt Data is set to Zone 2, Zone 3, the two events will be either Zone2 pickup or Zone 3 pickup, and any type of trip.

NOTE: All displayed Phase Angles use V

AG

as reference. A minimum of 0.5 A is re-quired for angle measurement.

d. TEST MODE

The test display mode provides diagnostic and testing capabilities for REL301/302. Relaystatus display, and relay output testing are among the functions provided.

Test Mode is selected by the SELECT push-button.

• Relay Self-Check Status

The REL 301/302 continuously performs self-checking. The results of the self-check are rep-resented by a hex value in the VALUE FIELD of the Status Function:

The results of the system self-check routines are accessible using the following procedure:

a. Depress the SELECT push-button until the TEST mode is displayed. Then, depress theRAISE or LOWER key until the word status appears in the FUNCTION FIELD.

b. The VALUE FIELD will display the status of the relay in hexadecimal Format.

For example: if the display shows status with a Value 1B.

Zone 1 f Trip on 1f AG

L-FLT

Inst f Trip

P-FLT

Status TEST 1B


86

The bit pattern which results from HEX Value 1B is described in detail in

Section 5.1.3

paragraphStep 5(a).

Relay Output Test

All relay outputs can be tested using the procedure described below

(1) Open the red FT switches, of the breaker trip circuits, making sure that the following FT switchis not opened:

FT-5 BFI/Reclose Enable

(2) Move the spare blue jumper to position JP5 on the Microprocessor module (refer to Table 5-3).

(3) Press the SELECT push-button until the TEST mode is displayed; then depress the RAISE orLOWER key until the output function to be tested appears in the FUNCTION and VALUE fields,respectively.

(4) Press the ENTER push-button for the desired duration of the output relays operation.

(5) Press the RAISE push-button to select the following parameters, as desired:

NOTE: Pressing the ENTER push-button operates selected output relays.

(6) After completion of this test, restore the system to its operating state by moving the blue jumperto position JP3 on the Microprocessor module, and closing the FT switch red handles.

4. 5. JUMPER CONTROLS

All jumpers are set at the factory; the customer normally does not need to move the jumpers. Referto

Tables 5-1, 5-2 and 5-3

for the recommended jumper positions.

FunctionField

ValueField Description

m RX1m RX2m RX1, RX2 Trip BFI RI2=3RI RBu Fail Alarm Trip Alarm Gen Startm Sendm Stops OC1s OC2s OC3s OC4s OC5/Stop

SimulateSimulateSimulateRelayRelayRelayRelayRelayRelayRelayRelayRelayRelayRelayRelayRelayRelay

Carrier Receiver #1 Simulated TestCarrier Receiver #2 Simulated TestCarrier Receiver #1 and #2 Simulated TestTripBreaker Failure3-Pole Reclose InitiateReclose BlockFailure AlarmTrip AlarmGeneral AlarmSendStopProgrammable Output Contact, 1Programmable Output Contact, 2Programmable Output Contact, 3Programmable Output Contact, 4Programmable Output Contact, 5/Stop

Note

:

m denotes for pilot option only.

u a Vac balanced 3-phase voltage must be applied to relay

for change of state to occur; without it the Failure alarm is

always in the Alarm State.

s denotes available with programmable contact output option.

I.L. 40-386.1

87

4. 6. COMMUNICATION PORT(S) USE

4.6.1 Introduction

REL 301/302 can be communicated with for target data, settings, etc., through the man-ma-chine interface (MMI), The relay can also be communicated with via one of the communication(comm.) ports. Comm port communications, provides the user with more information than isavailable with the MMI. For example, all 16 targets are available and a more friendly user inter-face for settings can be accessed (all settings are displayed on a single screen on the user’sPC). This section will provide the details of the comm port options, personal computer require-ments, connecting cables and all information necessary to communicate with and extract datafrom the relay. Additional communications details are contained in I.L. 40-603, (RCP)

RemoteCommunication Program.

As stated in Section 1.5, RCP is required for all comm. port com-munications. Information about the communications protocol can be found in the RCP I.L.

4.6.2 Communication Port Options

REL 301/302 is supplied with a rear communications port. If the network interface is not speci-fied, a RS-232C (hardware standard) communications port is supplied. Network interfacecomm. port option,

NET-PONI

(see I.L. 40-611 for details) allows the connection of the relaywith many other devices to a 2-wire network. A detailed discussion of networking capabilitiescan be found in

AD 40-600, Substation Control and Communications Application Guide

.

RS-232C, rear comm. ports are of the removable, Product Operated Network Interface (PONI)type and are available in two styles. One is identified by a 25 pin (DB-25S) female connector, itis usually black and has a single data comm. rate of 1200 bps. The second style is a

RS-PON

I(see I.L. 40-610 for details) identified by a 9 pin (DB-9P) male connector and externally acces-sible dip switches (next to the connector) for setting the communication data rate. This port op-tion is always black in color, can be set for speeds of 300, 1200, 2400, 4800, or 9600 bps (see

Table 4-7

) and offers an option for IRIG-B time clock, synchronization input.

Front communications is another comm. port option. The front panel RS-232C communicationsport, is supplied with a 9 pin (DB-9S) female connector and can be configured for 300, 1200,2400, 2400, 4800, 9600, or 19200 bps. Data comm. rate choice is made by dip switch settingswhich will be discussed later in this chapter.

4.6.3 Personal Computer Requirements

Communication with the relay requires the use of Remote Communication Program (RCP) re-gardless of the comm. port option. RCP is supplied by ABB Relay Division and is run on a per-sonal computer (PC).

NOTE: REL 301/302 relays should use latest version of RCP.

To run the program requires an IBM AT, PC/2 PC or true compatible with a minimum of 640kilobytes of RAM, 1 hard disk drive, a RS-232C comm. port and a video graphics adapter card.The PC must be running Version 3.3, or higher, MS-DOS.

4.6.4 Connecting Cables

With each comm. port option the connecting cable requirement can be different. Also, connect-ing directly to a PC or connecting to a modem, for remote communication, affects the connectingcable requirements. Table 4-5 provides a summary of a plug pin assignments, pins required andcable connectors.


88

Some terminology will be defined to aid the user in understanding cable requirements in Table4-5. Reference, is often made to the “RS-232C” standard, for data communication. The RS-232C standard describes mechanical, electrical, and functional characteristics. This standard ispublished by the Electronics Industry Association (EIA) and use of the standard is voluntary butwidely accepted for electronic data transfer. ABB relay communications follows the RS-232Cstandard for non-network data communication.

Although the RS-232C standard does not specify a connector shape, the most commonly usedis the “D” shape connector. As stated in Section 4.6.2 above, all ABB relay communication con-nectors are of the “D” shape (such as DB-25S).

Data communication devices are categorized as either Data Terminal Equipment (DTE) or DataCommunication Equipment (DCE). A DTE is any digital device that transmits and/or receivesdata and uses communications equipment for the data transfer. DCE’s are connected to a com-munication line (usually a telephone line) for the purpose of transferring data from one point toanother. In addition to transferring the data, DCE devices are designed to establish, maintain,and terminate the connection. As examples, a computer is a DTE device and a modem is a DCEdevice.

By definition the connector of a DCE is always female (usually DB-9S or 25S). Similarly, DTEsare always male (usually DB-9P or 25P). These definitions apply to the equipment being con-nected and to the connectors on the interconnecting cables.

One additional piece of hardware that is required, in some applications, is a “null” modem. Nullmodem’s function is to connect the transmit line (TXD), pin 2 by RS-232C standard, to the re-ceive line (RXD), pin 3. A null modem is required when connecting like devices. That is DTE toDTE or DCE to DCE. A DCE to DCE, example, where a null modem is required, is the connec-tion of a 25 pin, PONI to a modem.

A null modem function can be accomplished in the connecting cable or by separate null modempackage. That is, by using a conventional RS-232C cable plus a null modem. One type of nullmodem, available from electronics suppliers, is B & B Electronics Type 232MFNM.

4.6.5 Relay Password and Settings Change Permission

To gain access to certain communication port(s) functions, the REL 301/302 must have the re-mote setting capability permission

“Rem. Set”

set to

“Remote Allowed”

and knowledge of therelay password is required. All communications port functions listed below require

“Rem. Set”

set to


before the actions can be performed:

Update/Change SettingsUpdate Programmable Contact SettingsEnable Local Settings (capability)Disable Local Settings (capability)Activate Output Relays (contact testing function)

Access control, both setting permission and password knowledge is required for all communi-cation port options.

Before attempting any of the above functions, the setting of

“Rem. Set”

must be verified via thefront panel MMI. Using the setting change procedure in

Section 4.4.2.1

, verify or change

“Rem.Set”

such that it is set to


.

I.L. 40-386.1

89

Using comm. port communications, the ability to change settings from the MMI can be dis-abled.The RCP, Password Menu Choice “Disable Local Settings” when selected, will block set-ting changes via the MMI. Blocking the front panel setting changes, may be useful for situationsin which the access to the relay cannot be secured from tampering by unauthorized persons.

Password:

When the REL 301/302 is received from the factory or if the user loses the relay password, anew password can be assigned with the following procedure:

1) Turn off the relay dc supply voltage for a few seconds,

2) Restore the dc supply voltage and wait for the relay to complete the self check/start-uproutine,

3) Using RCP, perform the Password Menu choice “Set Relay Password”,

4) Use the word “password” when prompted for the “current relay password” and

5) Then enter a new password.

NOTE: Password setting change procedure must be completed within 15 minutesof energizing relay or “password” will not be accepted as the “current”password.

4. 7. FRONT RS-232C COMMUNICATIONS PORT

4.7.1 Communications Port Set Up

The front RS-232C comm. port, on the relay, consists of a printed circuit board that plugs flatinto the rear of the microprocessor module. On the front panel, of the relay, is the 9-pin (DB-9S)DCE connector with it’s associated enabling push-button, next to the connector. As describedabove, communications with the relay requires a serial cable from the comm. port to the com-municating device (usually a local PC).

The front comm. port data rate must match the comm. port data rate of the device connected tothe port. This data rate is set when configuring communications on the communicating device.If the communicating device is a PC, the data rate is set by RCP either when setting up RCP orby changing settings while running RCP.

To select the data rate on the front comm. port, the five pole dip switch S1 must be set accordingto Table 4-6. When the relay is viewed from the front, (front cover removed) the switch S1 islocated on the right side of the front panel near the top. (On the top of the front panel and on theleft for horizontally mounted relays.) Only the first three poles, #1, #2 and #3, of the switch, areused to set the communications bit rate. Refer to Table 4-6 for the correct position of the switchpoles. Note that settings 110 and 111 result in the default bit rate of 1200 bps.

4.7.2 Operations

When the communication hardware is in place, communicating with the front port requirespressing the push-button beside the connector in order to switch from the rear port to front port.There after, the communication will remain with the front until no data transfer has taken placefor fifteen minutes. After the fifteen times out, the active communications port returns to the rearport. The push-button can be pressed again to enable an additional fifteen minutes of front portcommunication activity.


90

RCP operations are identical for front and rear communication (RS-232C or INCOM). It is pos-sible that the communication is unsuccessful the first time after a relay power-up or switchingbetween protection and recloser. In this case, a second attempt usually proves to be successful.

4.7.3 Troubleshooting

In the event the communication remains unsuccessful, first make sure that the front communi-cation push-button has been depressed, the relay is powered and the connection is solid.

For further testing, remove the front cover and check that the bit rate (baud) on the communi-cation board (dip switches: refer to Dip Switch Setting Chart

Table 4-6

) is set to correspond tothe one displayed at the bottom right of the RCP display.

If after these verifications the problem remains, try to remove the power from the relay and applyit again. If the communication still fails (several attempts), the communication board needs tobe serviced.

4. 8. SIXTEEN FAULT TARGET DATA

The REL 301/302 saves the latest 16 fault records, but only the latest two fault records can beaccessed from the front panel. For complete 16 fault data, one of the communication interfacedevices are necessary. The activation of fault data storage is controlled by setting FDAT. Referto Section 2.4.17.1 for detailed information.

4. 9. OSCILLOGRAPHIC DATA

Sixteen sets of oscillographic data are stored in REL 301/302. Each set includes seven analogtraces (Va, V

b

, V

c

, I

a

, I

b

, I

c

and I

n

), with one cycle pre-fault and 7-cycle fault information, and 20sets of digital data based on 8 samples per cycle. Refer to Section 2.4.18.2 for detailed infor-mation.

NOTE: IF POWER IS INTERRUPTED TO RELAY ALL PRIOR “INTERMEDIATE TARGETDATA” AND “OSCILLOGRAPHIC DATA” WILL BE LOST.

4. 10. PROGRAMMABLE CONTACT OUTPUTS

(Optional Feature)

REL 301/302 has five output contacts OC-1 to OC-5 which can be dedicated to user-selectedfunctions, OC-1 has the same rating as the trip contacts. OC-2 - OC-5 have the same rating asnon-trip contacts. See

Section 1.6.3

for contact ratings. The 30 available functions are listed in

Table 4-4

. Each function can be inverted if desired. For REL 302 (Pilot) OC-5 is preprogrammedwith the STOP function. However OC-5 is fully programmable and can be changed by the user.

Logic AND & OR.

Several functions can be directed to one contact, using either an OR or anAND operator. With OR, any selected function operates the contact, whereas with AND all theselected functions need to be active in order to operate the contact. A pickup and a dropout tim-er can also be individually set for each programmable contact output.

Programming the output contacts is made via RCP and requires the password to be entered.An example of the programmable contact output screen is shown at the end of this section.

Connect Function to Output

. Selecting a function for an output contact is made by first tog-gling the <F2> function key to select Logic True (T) or Logic Negation (F). The current logic is

I.L. 40-386.1

91

shown on the right side of the display under contact 5 Dropout Timer selection. Then move thecursor with the arrow keys to the intersection of the desired function and contact, then press theINSERT key. T for logic true or F for logic Negation will show at that position. If is desired toremove the selection, the DELETE key can be used to de-select a previously selected function.

If a contact is to be controlled by several functions, the same procedure applies for each func-tion, without forgetting the combining operator OR or AND, shown at the beginning of each con-tact line.

Time Delay Pickup and Dropout

. To set the timers, move the cursor to the desired timer, lo-cated beneath the contact output table and press ENTER. The value to be set is displayed inthe upper right corner of the screen and can be adjusted with the Up or Down direction keysfollowed by ENTER when the desired time is displayed.4 Timer setting selection can be accel-erated by using the Page Up and Page Down direction keys. Each timer can be set from 0 -2000 cycles in 1 cycle increments, with an accuracy of

±

0.5 cycle.

4.10.1 Programmable Contact Outputs Applications

4.10.1.1 Breaker Failure Protection

A

Breaker Failure Scheme Using REL 301/302 programmable outputs and internally derivedovercurrent signals is described in the following. The REL 301/302's programmable logic capa-bilities permit its use in this application. The scheme can be simple, two contacts with time de-lays BF1 and BF2, or more complex using the two contacts mentioned plus one contact (OC1)as a Retrip and another contact, with time delay, as the control timer function. A simple schemeis described below.

Note: The input terminal P52a can be used as an external BFI. For the BFI applica-tion, the setting of ”52a/ManCls” on the Reclose setting menu MUST be set to“No, Disabled”.

Due to the operating time of the telephone relays, the BFI-A1 and BFI-A2 are 10 ms slower than the Trip A-1 and A-2.

1. Operation

When a breaker failure initiate (BFI) is detected, after the trip decision or via the P52a input, inconjunction with an overcurrent signal (IM or IOM), the pickup delay timers called BF1 and BF2begin timing. Seperate BF timers are used to allow individual settings for phase and groundfaults. The breaker failure times should allow ample marginto give the breaker an opportunity tointerrupt the current and clear.

At the end of the pickup time delay, BF1 or BF2, if BFI and the overcurrent signals are stillpresent, the breaker failure lockout 86BF will operate via programmable OC3 or OC4 (see

Fig-ure 4-4

). Transfer tripping, if applied, would then operate appropiate remote breakers to com-plete isolation of the failed breaker. If current above the settings of IM or IOM is not present, atthe end of the breaker failure time, all logic simply resets. Breaker failure timing considerationsare shown in the table at the top of the next page.


92

2. REL 301/302 Contact Programming

Each relay output contact can be programmed as a combination of internally generated signalsand an associated on delay and/or off delay timer(s). The programming is accomplished usingthe Relay Communications Program (RCP) and selecting the “UPDATE PROG CONT SET-TINGS” from the Password Commands menu. For complete details on using RCP, refer to

Sec-tions 4.6

and 4.7 and IL 40-603, RCP Remote Communication Program, USER’S GUIDE.

Programming of the contacts starts by establishing communication with the relay and selectingcontact programming choices screen. Programming each contact, and the associated timer(s),is explained in Section 4.10. When the contact programming is complete the contact program-ming choices screen should appear as in REL 301/302 PROGRAMMABLE CONTACT SET-TINGS (Breaker Failure) table, at the end of this section, with time delays filled in for each ofthe following:

BF1 = Breaker Failure Time (Phase)

BF2 = Breaker Failure Time (Ground)

R1,2 = Reset Time Delay

3. Settings

(a) Overcurrent units

The phase unit, IM, must be set below the minimum expected (CT secondary) phase fault cur-rent through the protected breaker, and the ground unit must be set less than the minimum ex-pected 3I0 fault current.

Settings should be made to assure a multiple of pickup of at least 2, under minimum fault con-ditions. Where the breaker contains a resistor, that is inserted on tripping, the overcurrent faultdetectors are set below the resistor current.

(b) Breaker failure timers (BF)

Breaker Failure Timing Diagram

Normal Clearing

Backup Breaker Failure Total Clear Time

Normal Clearing Time Local Remote

RELAY BKR INTERRUPT Margin

BFI BF1 & 2 TIMERS 86BF LOCAL BACKUP CLEARING

TT REMOTE BACKUP CLEARING

CONTROL TIMER CT R

Inoperative Breaker

I.L. 40-386.1

93

The breaker failure timers (BF1,2) should be set to exceed the breaker normal clearing time byan appropriate margin. A secure margin is 2 cycles (32 ms). Refer to Breaker Failure TimingDiagram (above). Often it is desirable to set the breaker failure times for different values forphase and ground faults.

(c) Reset Timers (R)

A small reset time is suggested to assure the 86BF lockout device has operated. OC3 and OC4have a low interrupting capability (see Section 1.6 for contact ratings).

4. External Connections

See Figure 4-4 for external connections to complete the breaker failure scheme.


94

Contact C P P 3 S 3 E P S P

A I Z Z Z Z L L I E O R I C C V I Z Z C L W T 5 I B L

Output O N F 2 2 3 3 G T T O N S I O R R Ø T 1 1 H T R F O 2 T I L F O

# R D T P G P G B G P S D B 2 M 1 2 T G G P O X B T P a P M V I P

1

2

3 X T T

4 X T T

5

Contact 1 Pickup Timer = cycle Contact 1 Dropout Timer = cycle


Contact 3 Pickup Timer = BF1 cycle Contact 3 Dropout Timer = R cycle

Contact 4 Pickup Timer = BF2 cycle Contact 4 Dropout Timer = R cycle


Use up, down, right, left arrows, Ins or Del keys for logic or Enter for timers.

F2: Toggle Logic Input; Logic True (T) or Logic Negative (F)

Contact C P P 3 S 3 E P S P

A I Z Z Z Z L L I E O R I C C V I Z Z C L W T 5 I B L

Output O N F 2 2 3 3 G T T O N S I O R R Ø T 1 1 H T R F O 2 T I L F O

# R D T P G P G B G P S D B 2 M 1 2 T G G P O X B T P a P M V I P

1

2

3

4

5 T

Contact 1 Pickup Timer = 0 cycle Contact 1 Dropout Timer = 0 cycle





Use up, down, right, left arrows, Ins or Del keys for logic or Enter for timers.

F2: Toggle Logic Input; Logic True (T) or Logic Negative (F)

Refer to Table 4-4 for a description of the functions

REL 301/302 PROGRAMMABLE CONTACT SETTINGS

Logic Input True

Logic Input True

(Breaker Failure)

REL 301/302 PROGRAMMABLE CONTACT SETTINGS(Factory Default Settings)

I.L. 40-386.1

95

Dtp drawing

123

456

78

910

11121314

1

2

3

4

Output

1

Output2

123

456

78

910

1

2

3

4

123456789

1011

1213141516171819202122232425262728

CommunicationsPort Connector

Use Mounting Stud ForCase Grounding

CommunicationsSpeed Dip SwitchRef: Table 4-2

Figure 4-1: REL 301/302 Terminals


96

*Sub 31613C80Sheet 1 of 2

Figure 4-2: REL 301/302 Systems External Connection

* Denotes Change

I.L. 40-386.1

97

Sub 31613C80Sheet 2 of 2

* SEE SHEET 1 FOR DETAILS OF FT SWITCH1 CONNECTIONS

Figure 4-3: REL 301/302 Systems External Connection

INS

TR

UC

TIO

N M

AN

UA

L R

EL

301/302

98

52TC

52a

86BF

+ DC Supply Voltage

- DC Supply Voltage

86 BF

OC1

OC2

OC3

OC4

BF TIME 1

BF TIME 2

TRIP A1FT-6

FT-8TB1-3

TB1-2

TB3-17

TB3-18

TB3-12

TB3-11

TB3-19

TB3-20

BREAKER FAILURE

Figure 4-4: REL 301/302 Breaker Failure DC Schematic

I.L. 40-386.1

99

Table 4-1: Setting Display

Setting

Function FieldValue Field

(Using 5 A and 60 Hz see note on Sheet 3)

Front Panel

RCP Front Panel RCP

Software Version Version VERSION Numerical NUMERICAL

Oscillographic Data Initiation Osc Data OSC Trip/Zone2/Zone2, Zone3/dV or dI TRIP/Z2TR/Z2Z3/dVdI

Fault Data Initiation Flt Data FDAT Trip/Zone2/Zone2, Zone 3 TRIP/Z2TR/Z2Z3

CT Ratio CT Ratio CTR 10 - 5000 10 - 5000

VT Ratio VT Ratio VTR 30 - 7000 30 - 7000

Rated Frequency Freq. FREQ 60 / 50 Hz 60 / 50 Hz

CT Secondary Rating CT Type CTYP 5 / 1 Amps 5 / 1 AMP

Read Out I and V in Primary or Secondary Units

Read Out RP Primary Units / Secondary Units YES/NO

Reactance for Fault Location X / Dist XPUD 0.300 - 1.500 W/mile or W/km depen-

dent on “DistUnit” Setting 0.300 - 1.500/DTY

Fault Location Units DistUnit DTYP Miles/Kilometers MILES/KM

Reclosing Mode RI Type TTYPNo RIØG RIØØ, ØG RI3Ø, ØØ, ØØG, ØG RI

Off1PR2PR3PR

High Speed RI Fast RI HSRINoneZ1/Inst IPilotPilot/Z1/Inst I

NOZ1/IPLTALL

RI on Zone2 Trip Zone2 RI Z2RI Yes/No YES/NO

RI on Zone3 Trip Zone3 RI Z3RI Yes/No YES/NO

Breaker Failure Reclose Block RemBF RB BFRB Yes/No YES/NO

Enable Pilot Logic Pilot PLT Yes/No YES/NO

Pilot System Selection SystType STYP

Non PilotZone1 ExtensionPOTTPUTTBlocking

3ZNPZ1EPOTTPUTTBLK

Forward Directional Ground Timer FDOGTime FDGT Blocked/0 - 15 cycles BLK/0 - 15 CYCL

Weakfeed Enable Weakfeed WFEN Yes/No YES/NO

3-Terminal Line Application 3-Term. 3TRM Yes/No YES/NO

Blocking System Channel Coordination Timer Blk Time BLKT 0 - 98 msec 0 -98 MSEC

Pilot Phase Setting Pilot Ø PLTP Disabled/ 0.01 - 50.00 OHMS OUT/0.01-50.00 OHMS

Pilot Ground Setting Pilot G PLTG Disabled/0.01 - 50.00 OHMS OUT/0.01-50.00 OHMS

Zone1 Phase Unit Zone1 Ø Z1P Disabled/ 0.01 - 50.00 OHMS OUT/0.01-50.00 OHMS

Zone1 Ground Unit Zone1 G Z1G Disabled/0.01 - 50.00 OHMS OUT/0.01-50.00 OHMS

Zone1 Delay Trip Timer T1 Timer T1 0 - 15 cycles 0 - 15 CYCL

Zone2 Phase Unit Zone2 Ø Z2P Disabled/0.01 - 50.00 OHMS OUT/0.01-50.00 OHMS

SET

(Sheet 1 of 3)


100

Zone2 Phase Timer– Timer Type

– Definite Time– Torque Control CO

Curve (with Time Delay or Inst. Reset)

– Torque Control Pickup

– Torque control Time Curve

T2Ø Type

T2Ø TimeT2Ø CV

T2Ø PkUp

T2Ø TC

Z2PT

T2PTP2CV

T2PPU

T2PTC

Blocked/Definite Time/Torque Control

0.10 - 2.99 secCO-2/C0-5/C0-6/CO-7 /CO-8/CO-9/CO/11 Each w/Reset or Inst

0.50 - 10.00 Amps

1 - 63

DISAB/DEFTM/TORQ

0.100 - 2.99 SECCO-2/5/6/7/8/9/11 I/R

0.500 - 10.00 AMPS

1 - 63


Zone2 Ground Timer–Timer Type

– Definite Time– Torque Control CO

Curve (with Time Delay or Inst. Reset)

– Torque Control Pickup

– Torque Control Time Curve

T2G Type

T2G TimeT2G CV

T2G Pickup

T2G TC

Z2GT

T2GT2GCV

T2GPU

T2GTC

Blocked/Definite Time/ Torque Control

0.10 - 2.99 SecCO-2/CO-5/CO-6/CO-7/CO-8/CO-9/CO-11 Each w/Reset or Inst

0.50 - 10.00 Amps

1- 63

DISAB/DEFTM/TORQ

0.100 - 2.99 SECCO-2/5/6/7/8/9/11 I/R

0.500 - 10.00 AMPS

1- 63

Zone3 Phase Unit Zone3 Ø Z3P Disabled/0.01 - 50.00 OHMS OUT/0.01-50.00 OHMS

Zone3 Phase Timer T3 Ø T3P Blocked/0.10 - 9.99 Sec BLK/0.10 - 9.99 SEC


Zone3 Ground Timer T3 G T3G Blocked/0.10 - 9.99 Sec BLK/0.10 - 9.99SEC

Zone3 Direction Zone3 Z3FR Forward Dir.Reverse Dir.

FWDREV

Pos. Seq. Line Impedance Angle Ang Pos. PANG 10 - 90O 10 - 90 DEG

Zero Seq. Line Impedance Angle Ang Zero GANG 10 - 90 O 10 - 90 DEG

Z0L/Z1L Z0L/Z1L ZR 0.1 - 10.0 0.100 - 10.00

Low Voltage Unit Low V LV 40 - 60 Volts 40 - 60 VOLTS

Overcurrent Units:– Low Set Phase– Medium Set Phase– Low Set Ground– Medium Set Ground– High Set Phase– High Set Ground

Low I ØIM3I0s3I0mInst. ØInst. G

ILIMIOSIOMITPITG

0.50 - 10.00 Amps0.50 - 10.00 Amps0.50 - 10.00 Amps0.50 - 10.00 AmpsDisabled/ 2.0 - 150.0 AmpsDisabled/ 2.0 - 150.0 Amps

0.500 - 10.00 AMPS0.500 - 10.00 AMPS0.500 - 10.00 AMPS0.500 - 10.00 AMPSOUT/ 2.00-150.0 AMPSOUT/ 2.00-150.0 AMPS

Out-of-Step Block OS Block OSB Yes/No YES/NO

OSB Override Timer OSOT OSOT 400 - 4000 msec 400 - 4000 msec

OSB Inner Blinder OS Inner RT 1.00 - 15.00 OHMS 1.0 - 15.0 OHMS

OSB Outer Blinder OS Outer RU 3.00 - 15.00 OHMS 3.00 - 15.00 OHMS

Directional Overcurrent Dir Type DIRUZero SequenceNegative SequDual Polariz

ZSEQNSEQDUAL


Setting



Front Panel

RCP Front Panel RCP

SET

(Sheet 2 of 3)

I.L. 40-386.1

101

NOTE: WHEN THE CTYP FUNCTION IS SET AT 1 AMPERE, THE RANGE OF THE FOL-LOWING FUNCTIONS ARE AS SHOWN BELOW:

• ZIP/ZIG/ZEP/Z2G/Z3P/Z3G/PLTP/PLTG 0.05-250.00, in 0.05 W steps.

• ITP/ITG 0.4-30.0, in 0.1 A steps.

• IL/IM/IOS/IOM 0.1-2.0, in 0.02 A steps.

NOTE: SEE ALSO SECTION 3.3.6, SELECTIONS OF CTYP SETTINGS.

NOTE: The increments of timers are based on the line frequency, e.g., 16 msec for 60Hz and 20 msec for 50 Hz (to the nearest msec).

Directional Overcurrent Ground Backup Time Curve Family (With Time Delay or Inst. Reset)

GB Type GBCV Disabled/CO-2/CO-5/CO-6/CO-7/CO-8/CO-9/CO-11 (Each w/Reset or Instant)

OUT/CO-2/5/6/7/8/9/11 I/R

Ground Backup Pick-up GBPickup GBPU 0.50 - 4.00 Amps 0.500 - 4.00 AMPS

Ground Backup Time Curves within Family GBTCurve GTC 1 - 63 1 - 63

Choice of Directional or Non-Directional Ground Backup

GB Dir. GDIR Yes/No YES/NO

Close-Into-Fault Trip CIF Trip CIFCIF TripCIF Trip w/delayNo CIF Trip

CFCFTOUT

Load Loss Trip LL Trip LLT Yes/FDOG/No YES/NO/FDOG

Loss of Potential Block LOP Blk LOPB Yes/All/No YES/NO/ALL

Loss of Current Block LOI Blk LOIB Yes/No YES/NO

Trip Alarm Seal-In Trip Alm AL2S Seal-In/No Seal-In YES/NO

Remote Setting Change Enable Rem. Set —— Remote Allowed/No Remote ————

Real Time Clock Set1. Set Year2. Set Month3. Set Day4. Set Weekday5. Set Hour6. Set Minute

Set TimeYearMonthDayWeekdayHoursMinutes

——

Yes/No1980 - 20791 - 121 - 31Sunday through Saturday0 - 230 - 59

————


Setting



Front Panel

RCP Front Panel RCP

(Sheet 3 of 3)

SET


102

Table 4-2: Metering Display

Front Panel

Function Field

Value Field

Phase A Current (Magnitude & Angle) IA: Magnitude (A) and Angle (°)

Phase A Voltage (Magnitude & Angle) VAG: Magnitude (V) and Angle (°)

Phase B Current (Magnitude & Angle) IB: Magnitude (A) and Angle (°)

Phase B Voltage (Magnitude & Angle) VBG: Magnitude (V) and Angle (°)

Phase C Current (Magnitude & Angle) IC: Magnitude (A) and Angle (°)

Phase C Voltage (Magnitude & Angle) VCG: Magnitude (V) and Angle (°)

Time and Date TimeDate

Local, Remote or Both Setting Control Settings

Carrier Receive-1 (Yes or No) Rx Ch1

Carrier Receive-2 (Yes or N0) Rx Ch2

Date Of Last Setting Change Last Set

LOP Condition if present LOP

LOI Condition if present LOI

Out-of-Step Block if present OS Block

RCP

Function Value Value Field Function Value Value Field

VAG MAG =ANG =

_ _ _ VOLTS_ _ _ DEG.

IA MAG =ANG =

_ _ _ AMPS_ _ _ DEG.

VBG MAG =ANG =

_ _ _ VOLTS_ _ _ DEG.

IB MAG =ANG =

_ _ _ AMPS_ _ _ DEG.

VCG MAG =ANG =

_ _ _ VOLTS_ _ _ DEG.

IC MAG =ANG =

_ _ _ AMPS_ _ _ DEG.

V1 MAG =ANG =

_ _ _ VOLTS_ _ _ DEG.

I1 MAG =ANG =

_ _ _ AMPS_ _ _ DEG.

V2 MAG =ANG =

_ _ _ VOLTS_ _ _ DEG.

I2 MAG =ANG =

_ _ _ AMPS_ _ _ DEG.

3V0 MAG =ANG =

_ _ _ VOLTS_ _ _ DEG.

3I0 MAG =ANG =

_ _ _ AMPS_ _ _ DEG.

DATE = 10/28 POWER FLOW=

_ _ _ WATTS

TIME = 11:20 VAR FLOW = _ _ _ VARS

LOI = NO (STATUS) PF ANGLE = _ _ _ DEG.

LOP = YES (STATUS) PF = _ _ _

OSB = NO (STATUS) SETTING STAT=

BOTH

RX1 = NO (STATUS) —— ——

RX2 = NO (STATUS) —— ——

METER

I.L. 40-386.1

103

Table 4-3: Target (Fault Data) Display (2 Pages)

Information

Function Value

Front Panel

RCP Front Panel RCP

Fault Type Flt type FTYPAG/BG/CG/AB/BC/CA/ABG/BCG/CAG/ABC/Blank if other/Test

AG/BG/CG/AB/BC/CA/ABG/BCG/CAG/ABC/Blank if other/TEST

Breaker 1 Tripped Breaker 1 BK1 Yes/No YES/NO

Breaker 2 Tripped Breaker 2 BK2 Yes/No YES/NO

Zone1 Phase Trip Zone1 Ø Z1P Yes/No YES/NO

Zone1 Ground Trip Zone1 G Z1G Yes/No YES/NO





Pilot Phase Trip Pilot Ø PLTP Yes/No YES/NO

Pilot Ground Trip Pilot G PLTG Yes/No YES/NO

Carrier Send Car Send SEND Yes/No YES/NO

Receiver 1 Rx Ch1 RX1 Yes/No YES/NO

Receiver 2 Rx Ch2 RX2 Yes/No YES/NO

Weakfeed Trip Weakfeed WFT Yes/No YES/NO

High Set Phase Trip Inst. Ø ITP Yes/No YES/NO

High Set Ground Trip Inst. G ITG Yes/No YES/NO

Close-Into-Fault Trip CIF Trip CIF Yes/No YES/NO

Load-Loss Trip LL Trip LLT Yes/No YES/NO

Ground Backup Trip GB Trip GB Yes/No YES/NO

Fault Location Imp. Flt ZFANG

Magnitude (W) and angle (°)Magnitude (W) and angle (°)

OHMSDEG.

Fault Distance Flt Dist DMI/DKM in Miles or Kilometers MILES/KM

Prefault Load Current PFlt I PFLC Numerical in Amps Numerical in AMPS

Prefault Phase Volt-age

PFlt V PFLV Numerical in Volts Numerical in VOLTS

Prefault Load Angle PFlt Ang LP Numerical in Degrees Numerical in DEG

Phase A Fault Volt-age

VAG Flt VPA MAGANG

Magnitude (V)Angle (°)

VOLTSDEG.

Phase B Fault Volt-age

VBG Flt VPB MAGANG

Magnitude VoltsAngle (°)

VOLTSDEG.

Phase C Fault Volt-age

VCB Flt VPC MAGANG


VOLTSDEG.

NOTE: On front panel display, all Yes or No information displayed when the answer is “YES”

L-FLT


104

3V0 Fault Voltage 3V0 Flt 3V0 MAGANG


VOLTSDEG.

Phase A Fault Current IA Flt IPAMAGANG


VOLTSDEG.

Phase B Fault Current IB Flt IPB MAGANG


VOLTSDEG.

Phase C Fault Current IC Flt IPCMAGANG


VOLTSDEG.

IP Fault Current IP Flt INMAGANG

Magnitude Volts)Angle (°)

VOLTSDEG.

Date of Fault Date Flt —— Month/day and year ——

Time of Fault Time Flt —— Hours, Minutes, Seconds and Hundredths

——

Information

Function Value

Front Panel

RCP Front Panel RCP

NOTE: On front panel display, all Yes or No information displayed when the answer is “YES”

L-FLT

I.L. 40-386.1

105

List of the 30 functions to choose from for the programmable contact outputs.

Function Description

OR Logic OR when several functions are combinedAND Logic AND when several functions are combined

CIFT Close into fault tripZ2P Zone2 phase Trip PickupZ2G Zone2 ground Trip PickupZ3P Zone3 phase Trip PickupZ3G Zone3 ground Trip PickupGB Ground backup (overcurrent) Trip PickupPLTG Pilot ground tripPLTP Pilot phase trip3IOS Low set ground overcurrent indicationSEND Carrier SendOSB Out-of-step block pickupRI2 Reclose initiationIOM Mediumset overcurrent groundCR1 Receive Channel 1 signalCR2 Receive Channel 2 signal3VØT Produce an output when 3VØT > 105 voltsITG High set overcurrent ground tripZ1G Zone1 ground tripZ1P Zone1 phase tripECHO Weakfeed echo keyPLTX Pilot in service (includes external 85CO input)RB Reclosing blockWFT Weakfeed tripSTOP Carrier stopP52a 52a input terminal sensingITP High set overcurrent phase tripIM Mediumset overcurrent phaseLV Low voltageBFI Breaker failure initiationLOP Loss of potential pickup

NOTE: The pickup and dropout timers can be set between 0 and 2000 cycles in 1 cycle steps.

Table 4-4: Programmable Contact Outputs


106

Table 4-5: Communications Cable Requirements

* Note: A communications cable kit (item identification number 1504B78G01) that will accommodate most connec-tion combinations (* in Table 4-5), is available through your local ABB representative.

Table 4-6: Dip Switch Setting Chart

Table 4-7: RS-PONI (9-Pin) Communications Speed Setting

NOTE: The RS PONI Dip Switches are acessible from the top rear of REL 301/302. (ref. figure 4-1)

Connection Type Cable(Straight =

nonull modem)

Pins Req’d.(All pins

not required)

Cable Connectors Notes

DB-25S, RS-232C connected to PC* Straight 2, 3, 7 To port: 25 pin DTETo PC: 9 or 25 pin DCE

DB-25S, RS-232C connected to modem

Null Modem 2, 3, 7 To port: 25 pin DTEto Modem: 25 pin DTE

DB-9P, RS-232C connected to PC* Null Modem 2, 3, 5 To port: 9 pin DCETo PC: 9 or 25 pin DCE

See IL 40-610 For set-tings

DB-9P, RS-232C connected to modem*

Straight 2, 3, 5 To port: 9 pin DCETo Modem: 25 pin DTE

See IL 40-610 For set-tings

DB-9S, RS-232C connected to PC* Straight 2, 3, 5, 7, 8 To port: 9 pin DTETo PC: 9 or 25 pin DCE

See Table 4-6 For set-tings

DB-9S, RS-232C connected to modem

Null Modem 2, 3, 5, 7, 8 To port: 9 pin DTETo Modem: 25 pin DTE

See Table 4-6 For set-tings

Dip Switch Pole

1 2 3

Port Data Rate

(bps)

0 0 0 300

Logic 1 is towardsPrinted Circuit Board

Dip Switch poles 4 & 5are not used

0 0 1 1200

0 1 0 2400

0 1 1 4800

1 0 0 9600

1 0 1 19200

1 1 0 1200

1 1 1 1200

DIP Switch1 2 3 BPS

0 0 00 0 10 1 00 1 11 0 01 0 11 1 01 1 1

3001200240048009600

1920012001200

NOTE: DIP switches 4 and 5 are not used

I.L. 40-386.1

107

PURPOSE

The purpose of this procedure is to provide a test that can be used for incoming inspection orto determine at any time if the REL 301 or 302 is functioning correctly. The Acceptance Testconfirms that a particular unit is serviceable with a minimum of time and effort. During the Ac-ceptance Test the emphasis is on hardware verification.

If the reader’s goal is to completely evaluate REL 301 and/or REL 302 firmware, the

Engineer-ing Evaluation Test Manual

is recommended for that purpose. The manual is intended to aidthe user in understanding the software design and/or decide if the REL 301 or REL 302 is suit-able for a specific application. For further details see Engineering Evaluation

Test Manual, TM40-386.

The Acceptance Test Will Cover:

• Front Panel, Man-Machine-Interface (MMI) testSelf test relay status displayMetering mode display testSettings application

• Hardware Verification

• Impedance Accuracy Check

• Tests of all inputs and contact outputs

• Additionally, if the relay under test is a REL 302, the pilot logic and pilot distance measuringfunction will be tested.

Test Equipment:

The minimum test equipment required is:

• One 3-phase, variable (magnitude and phase angle), Y-connected voltage source

• One 1-phase, variable (magnitude and phase angle), current source synchronized to the volt-age source

• Two Flexitest (FT) test plugs

• Appropriate test leads and hand tools

The test equipment can be in the form of popular multi-function test equipment, such as theequipment offered by AVO International Multi-Amp, Doble Engineering Company or PowertecIndustries Inc., or by using conventional phase shifter, load box, various test setups.

! CAUTION

Before energizing the relay it is extremely important to check that all jumpers on thefilter, power supply and microprocessor modules are in the correct position.

Section 5. REL 301/302 ACCEPTANCE TEST

AND PERIODIC MAINTENANCE PROCEDURES


108

Acceptance Test

Before beginning any testing, verify that voltage selectable input, and contact configurationjumpers are in the correct position. The following tables, with appropriate reference figures, willprovide a guide for the jumper settings. In-service settings may vary according to specific appli-cations.

Table 5-1: Filter Module Jumper Settings

Filter ModuleSee Figure 5-1

for Location

Jumper Identification Jumper Purpose Factory Setting

P2 52 a Input Voltage Selection 48/125 Vdc

P18 52 b Input Voltage Selection 48/125 Vdc

P7 External Reset Input Voltage Selection 48/125 Vdc

P9 Pilot Enable Input Voltage Selection 48/125 Vdc

P10 Receiver 1 Input Voltage Selection 48/125 Vdc

P12 * Sync-Check Voltage Reference VA

P13 Receiver 2 Input Voltage Selection 48/125 Vdc

* When using the 120 V option, Jumper setting V

A

= V

AB

, V

B

= V

BC

, V

C

= V

CA

Table 5-2: Power Supply Module Jumper Settings

Power Supply Module See Figure 5-2 for Location


JMP1 Carrier Stop Normally Open NO

JMP2 Carrier Send Normally Open NO

JMP5 Output contact 4 Normally Open NO

JMP4 Output Contact 3 Normally Open NO

JMP3 Output Contact 2 Normally Open NO

JMP6 Relay Fail Alarm AL1 Normally Closed NC

JMP7 Relay Trip Alarm AL2 Normally Open NO

Table 5-3: Microprocessor Module Jumper Settings

Microprocessor Module ** See Figure 5-3 for Location


JP3 Spare Jumper Storage IN (Jumper Present)

JP4 Trip Dropout Delay OUT (No Jumper)

JP5 Enable Output Test OUT (No Jumper)

JP6 A/D Calibration OUT (No Jumper)

** To verify or change jumper positions on the microprocessor module it is necessary to remove the front panel of the REL 301/302.

I.L. 40-386.1

109

To prepare the relay for testing, it is necessary to make certain test connections. Test connec-tions can be made to the rear terminals of the relay, or through test plugs and built-in FT switch-es. The easiest connection, for the voltage and current inputs, is through the FT test plugs andtest switches.

NOTE: When using the conventional FT switch test plugs, it is recommended to re-move the front nameplate to allow the plug to be fully inserted in the switchjaws.

5. 1. NON-PILOT ACCEPTANCE TESTS FOR REL 301/302

5.1.1 Front Panel Man-Machine-Interface (MMI) Test

REL 301/302 front panels consists of 9 Light Emitting Diodes (

LED

s)

1

,

R

ESET

2

push-button andthe Man-Machine-Interface (MMI) which includes a 2 line (16 character per line) Liquid CrystalDisplay (LCD) with 4 push-buttons. All settings, two most recent targets, display quantities andrelay test functions can be accessed with the MMI. For acceptance testing, the MMI will be ref-erenced for all access to and data acquisition from the relay. See

Figure 1-5

for a detailed layoutof the front panel with MMI.

If the system under test is not equipped with the MMI or it is desired to utilize one of the com-munication ports, all access to and data acquisition from the relay can be accomplished. Datacommunications via the communication ports will not be covered in this procedure. (Refer to

Section 4.6

for complete details.)

If the relay under test is equipped with reclosing the front panel has additional LEDs (up to 6with sync check) and the MMI has a switch to toggle between the reclosing settings and protec-tion settings. Separation of reclosing settings from protection settings alleviates the need toscroll through the reclosing settings when protection settings are in progress.

STEP 1

To begin the test procedure apply rated dc voltage to terminals

F

T

-11

(+) and

F

T

-20

(-). The dcvoltage rating of the relay is stated on the front nameplate. Upon application of the appropriatedc voltage, the relay will complete a self-test/startup/initialization routine. If the startup routine issuccessfully completed, the

PROTECTION IN SERVICE

LED will light. The LCD display entersthe

“METER”

3

mode and displays the A phase current magnitude. (At this time the A phase cur-rent will read 0.0 amp and no angle will be displayed.) If the

PROTECTION IN SERVICE

LEDdoes not light, check the dc supply voltage and connections.

Using the

R

AISE

or

L

OWER

push-button to scroll (forward or backward, respectively) all meteringmode quantities can be reviewed. See

Table 4-2

for complete details of the

“METER”

displaymode quantities.

MMI is accessed by pressing the

S

ELECT

push-button, to scroll sequentially through the five dis-play modes,

“METER”

(ing),

“L-FLT”

(Last FauLT),

“P-FLT”

(Previous FauLT),

“TEST”

, andSET(ing). Current display mode is shown in the upper right corner of the LCD display. (See

Sec-tion 4.4.2

for more details.)

1. Bold italic type indicates an output e.g.

LED

s or contact output.2. Bold type, with small capital letters, indicates an input e.g.

R

ESET

push-button or voltage inputs.3. Bold type in quotation marks indicates LCD display quantities


110

Press the

S

ELECT

push-button and scroll to the

“TEST”

display. The display should read

“STA-TUS” “0”

indicating the self-checking/startup/initialization routine was completed successfullyand the system is continuously passing the self-checking routine.

STEP 2

Press the

S

ELECT

push-button until you reach the “SET” mode. Displayed is the firmware VER-SION number. Verify the VERSION number agrees with the version number shown on the coverof this instruction literature.

NOTE: Pressing the RESET push-button, at any time, will reset the target LED’s andcause the display to return to the METER display mode.

STEP 3

The settings used for the first test, impedance accuracy test, are shown in Table 5-4 (Table 5-5 for REL 302). Table 5-4 (or 5-5) settings should be applied to the relay at this time.

To enter the settings, press the SELECT push-button again until the SET mode is indicated.Then load all settings, one after the other, by using the following procedure to select, set andaccept

each

setting.

When all settings have been entered, the entire settings set should bereviewed for correctness before continuing with this procedure.

Setting application example OSC Data setting:

1. Press the RAISE push-button to display the “OSC Data” setting (upper-left corner of thedisplay).

2. Press the ENTER push-button to enable the value to be changed.

3. Press the RAISE push-button to display “OSC Data” to “Trip”.

4. Press the ENTER push-button to accept the new setting value.

5. The LCD display of “Value Updated!” Indicates the setting change is accepted.

6. Press the RAISE push-button to display the next setting and repeat Steps 1 thru 4 above.

NOTE: The ENTER push-button must be pressed to select each setting change indi-vidually, not the entire group of settings.

NOTE: Before continuing with this procedure verify the “Freq” and “CT Type” settingsmatch the line frequency and current transformer input being used.

5.1.2 Input quantities Verification and Metering Display

STEP 4

Connect the test source according to Figure 5-4. This connection will be used for verification ofthe Alarm 1 relay operation and the METER mode display. This connection will also be used forthe first test.

I.L. 40-386.1

111

Apply a balanced 3-phase voltage:

V

A

= 70 ang 0

°

V

B

= 70 ang -120

°

V

C

= 70 ang 120

°

Failure Alarm (AL-1) relay contacts (Terminals TB3-25 and TB3-26) are closed before the bal-anced voltage is applied. After applying the balanced voltage verify the normally closed contactsare open. That is, not in the alarm state.

Press the SELECT push-button again until the METER mode is selected. Displayed is the Aphase current, “IA:” and the value “0.0A”, since no current is being applied, and the current angleis blank. For any current value less than 0.5A, no current angle is displayed. This is also true forcurrents IB and IC.

NOTE: ALL angle measurements (voltages and currents) are with reference to the Aphase voltage (VAG) which is always assumed at zero degrees, relative.

Press the RAISE or LOWER push-button to view the other currents, voltages and associatedangles. See Table 4-2 for the details of the “METER” mode displayed quantities.

5.1.3 “TEST MODE”

The “TEST” display mode provides diagnostics and testing capabilities for REL 301/302. Relayself-check routine results, as previously described in Step 1 above, and output relay contacttesting are among the functions in the “TEST” mode. Also included is the ability to test front pan-el LED’s and verification of selected contact inputs.

NOTE: In order to test the output contacts, place a jumper in the JP-5 position and re-move this jumper after the test.

STEP 5

a. Press the SELECT push-button until the “TEST” mode is selected. Displayed is the resultof the self-test routine. Results of the self-check routine are represented by a hex numberin the VALUE FIELD of the “Status” function. A normal status, (relay system passing theself-check routine) is “STATUS” “0”. If REL 301/302 fails the self-check routine another hexvalue is displayed, which can be interpreted to provide failure mode information.

For example if the display shows “STATUS” “1B”, the binary equivalent which results is:

HEX VALUE 1 B

Binary Equiv. 0001 1011

Bit Number 7654 3210


112

Using the following table, failure mode can be determined by equating bit numbers (from above)to failure description. A bit set to “1” indicates the corresponding failure has been detected.

For reference the binary-to-hexadecimal conversion is shown below:

RELAY STATUS FAILURE MODE

FAILURE DESCRIPTION BIT NUMBER

RAM Failure 0

EEPROM* Warning** 1

EPROM Checksum Fail *** 2

EEPROM Failure 3

Analog Input Failure 4

Microprocessor Failure 5

* Electrically Erasable Programmable Read Only Memory (non - volatile memory** “EEPROM Warning” indicates a non-fatal error related to the failure of the EEPROM

check routine. All data stored in the EEPROM is written to 3 identical arrays.These arrays are continuously checked for agreement with each other. If any of the 3 arrays disagree (2 arrays must agree with each other) an “EEPROM Warning” is given. This is the only failure which does not take the protection out of service. (Also the “Protection In-Service” LED remains lighted.)

*** EPROM Checksum Failure indicates the program memory has failed.With the exception noted above, (“EEPROM Warning”) relay tripping is blocked to prevent false operation, upon failure of the self-check routine. Also the “Protection In-Service” LED goes out.

HEX DIGITBINARY

REPRESENTATION

0 0 0 0 0

1 0 0 0 1

2 0 0 1 0

3 0 0 1 1

4 0 1 0 0

5 0 1 0 1

6 0 1 1 0

7 0 1 1 1

8 1 0 0 0

9 1 0 0 1

A 1 0 1 0

B 1 0 1 1

C 1 1 0 1

D 1 1 0 1

E 1 1 1 0

F 1 1 1 1

I.L. 40-386.1

113

b. The “TEST” display mode also provides access for testing for REL 301/302 output relaycontacts. All output relays will be tested using the procedure described in Step 12. In asso-ciation with the contact test, receiver 1 and/or 2 units can be simulated for verification ofREL 302 pilot logic. These input simulations will be used later in

Section 5.2 Pilot Accep-tance Tests for REL 302.

As previously stated, when REL 301 or REL 302 are energized the system performs a completeself-test/startup/initialization routine. Upon successful completion of the startup routine the sys-tem firmware enters what is referred to as the background mode. In the background mode all“non-fault analysis” functions are performed. In the background mode, current and voltage sam-pling is done continuously (2 millisecond resolution) as well as the calculation of current andvoltage phasors. Also, when the system is in background mode MMI functions and (continuous)self-checking are performed. See Figure 1-6 for software flowchart reference.

Tripping decisions are made in the fault mode. Both the REL 301 and REL 302 utilize a uniquedisturbance detector that is used to switch from background mode to fault mode processing. Infault mode only processing related to fault calculation trip logic analysis are done. All back-ground mode functions not related to tripping are stopped.

The operate criteria for the disturbance detector (Fault Detector) are:

Phase current (

D

IA,

D

IB, or

D

IC) > 1.0A peak and 12.5% changeGround current (

D

I0)>0.5 A peakPhase voltage (

D

VA,

D

VB, or

D

VC) >7V and 12.5% change with a current change of

D

I>0.5 A

When one of the above is met, REL 301 or REL 302 will switch to fault mode processing.

In order to perform all tests, voltages will be applied first then the designated value of currenthas to be

suddenly

applied. If REL 301 or REL 302 does not trip, adjust the current to a highervalue, and then suddenly reapply current. Unlike conventional electromechanical relays, slowlyramping up the current will not cause Zone 1tripping. The current required to trip is shown foreach test.

5.1.4 Zone 1 Impedance Accuracy Check

STEP 6

The following impedance accuracy tests use a predetermined fault voltage and current for thetest impedance applied to the system under test. If it is desired by the user to test impedanceaccuracy at another impedance setting, the following formula can be used to calculate test cur-rent for any phase-to-ground fault, impedance setting:

where: PANG = “Ang Pos”Z

R

= Z

0L

/Z

1L

From Table 5-4 (for example):

•

“Zone1 G”

=

“4.5 Ohms”

IVLN

Z1GCOS PANG X–( ) 1ZR 1–( )

3---------------------+

----------------------------------------------------------------------------------------------=


114

•

“Ang Pos.”

=

“75

°

“

•

“ZOL/Z1L”

=

“3.0”

using: X = 75

°

(lagging)V

LN

= Fault voltage chosen for faulted phase, in this example 30 volts

The current required to trip = 4.00A +/-5 % for fault current lagging fault voltage by 75

°

. This isthe maximum torque angle test. For other points on the MHO circle, change X to a value be-tween 0

°

and 150

°

, and calculate the value of I.

With the system under test connected as shown in Figure 5-4 and with the settings from Table5-1 (5-2 for REL 302) applied to the system, adjust the voltages as follows:

V

A

= 30 ang 0

°

V

B

= 70 ang -120

°

V

C

= 70 ang 120°

Apply current to the A phase current input as shown. The current required to trip is 4.00 amps± 5% at an angle of 75° lagging the fault voltage. This is the “maximum torque angle” test.

When the relay trips, remove the fault current. Zone 1 and AG LED’s will light. The LCD displaywill indicate the fault distance. Using the RAISE and LOWER push-buttons the complete faultrecord can be reviewed. See Table 4-3 for a description of the displayed fault data quantities.

The significant quantities to review are:

Fault Type – “FLT Type” “AG”Targets – “Zone1G” “Yes”Fault Voltages (VA, VB, VC, 3V0 and Currents (IA, IB, IC, IP)

All trip associated contact outputs, should be monitored as a part of this test. Connect appropri-ate monitoring equipment to the “dry” contact outputs to be monitored. See Figures 4-1, 4-2 and4-3 for contact output connection. Additionally, with an external jumper connected betweenTB1-1 (SYST TEST) and FT-5 (BFI/RI ENA), the following can be observed:

1. Breaker failure initiate (BFI) BFIA-1 and BFIA-2 are closed as long as the fault is appliedafter the trip decision is made. BFI contacts “follow” the trip contacts.

2. General Start (GS) contact will pick-up for approximately 50 ms immediately after the faultis applied.

3. Trip alarm (Trip alarm, AL-2), relay will pick-up and remain picked up as long as the fault isapplied, after the trip decision is made. The AL-2 contact “follows” the trip contacts. Afterthe fault has been removed, AL-2 will remain picked up since the “Trip Alarm” is set to Seal-in. Alarm 2 can then be reset by pushing the RESET push-button.

4. Reclosing Initiation (RI) contacts RI-1 and RI-2 will not operate since the setting “RI type”is “No RI”. Change “RI Type” to “ØG RI” and re-apply the fault current. RI-1 and RI-2should pick-up for approximately 400 ms (after the trip decision has been made).

I.L. 40-386.1

115

Repeat the A phase-to-ground fault test and measure the trip time, which should be less than 2cycles.

The following formula can be used when PANG ¹ GANG:

Assume, PANG = “Ang Pos”, GANG = “Ang Zero”, ZR = ZoL/Z1L, Zcq = Setting of Zone-1G andx = phase a or b or c.

or

or

where

or

Example:

Vag = 30 Z1g = 4.5 PANG = 85GANG = 40 Zr = 3

This is the trip current (4.3A) at the maximum torque angle of -57.76˚ (current lags voltage by57.76˚).

The following equation should be used for the angle of x on the mho circle:

Vxg IX K0I0+( )Zcg=

Vxg IxK0Ix

3-----------+è ø

æ ö Zcg=

IXVxg

Zcg 1K0

3------+è ø

æ ö-------------------------------=

K0

Z0L Z1L–

Z1L------------------------è ø

æ ö=

ZR (GANG PANG)– 1–Ð=

IXVxg

Zcg ejPANG1 Zr ej GANG PANG–( )

1–3

------------------------------------------------------------+

------------------------------------------------------------------------------------------------------------=

IXVxg

Zcg ePANG 13--- Zcg Zr ejGANG

+----------------------------------------------------------------------------------=

Ia30

23--- 4.5( )ej85 1

3--- 4.5( ) 3( )ej40

+------------------------------------------------------------------=

303 (85) j3 (85) 4.5 (40) j4.5 (40)sin+cos+sin+cos-----------------------------------------------------------------------------------------------------------------------------=

4.31 57.76–( )Ð=

Iax30

6.96 57.76 x–( )cos------------------------------------------------=


116

Using Figure 5-5 and 5-6, repeat (preceding) step 6 for BG and CG faults. Note Targets.

STEP 7

Using the test connections shown in Figures 5-5 and 5-6, repeat Step 6 above for B phase-to-ground (BG) and C phase-to-ground (CG) faults respectively. The test voltages are shown be-low:

For BG fault test, make connections as shown in Figure 5-5 and adjust the voltages as follows:

VA = 70 ang 0°VB = VF = 30 ang -120°VC = 70 ang 120°

Apply current to the B phase current input as shown. The current required to trip is 4.00 amps± 5% at an angle of 75° lagging the fault voltage.

When the relay trips, remove the fault current. Zone 1 and BG LED’s will light. The LCD displaywill indicate the fault distance. Using the RAISE and LOWER push-buttons the complete faultrecord can be reviewed. See Table 4-3 for a description of the displayed fault data quantities.


Fault Type – “FLT Type” “BG”Targets – “Zone1G” “Yes”Fault Voltages (VA, VB, VC, 3V0) and Currents (IA, IB, IC, IP)

For CG fault test make connections as shown in Figure 5-6 and adjust the voltages as follows:

VA = 70 ang 0°VB = 70 ang -120°VC = VF = 30 ang 120°

Apply current to the C phase current input as shown. The current required to trip is 4.00 Amps± 5% at the angle of 75° lagging the fault voltage.

When the relay trips, remove the fault current. Zone 1 and CG LED’s will light. The LCD displaywill indicate the fault distance. Using the RAISE and LOWER push-buttons the complete faultrecord can be reviewed. See Table 4-4 for a description of the displayed fault data quantities.


Fault Type – “FLT Type” “CG”Targets – “Zone1G” “Yes”Fault Voltages (VA, VB, VC, 3V0) and Currents (IA, IB, IC, IP)

I.L. 40-386.1

117

5.1.5 Input Opto-Coupler Check (Also see Step 12)

STEP 8External Reset

Apply an AG fault as described pin Step 6 above. As stated the Zone 1 and AG LEDs will lightand begin flashing. The LCD display will switch to the “L-FLT” mode and fault distance will bedisplayed. Pressing the front panel RESET push-button will cause the LCD display switch to the“METER” display and the LED’s to stop flashing.

Again apply an AG fault. Again the Zone 1 and AG LEDs will light and begin flashing. The LCDdisplay will switch to the “L-FLT” mode and fault distance will be displayed. Apply rated dc volt-age to terminals TB4-7(+) and TB4-8(-). The LCD will display “FLT Type”, all fault data will beerased and the LED’s will stop flashing. Remove the voltage from TB4-7 and TB4-8.

STEP 952b Input

Using the MMI change the setting of “CIF Trip” from “No” to “Yes” using the procedure in Step4 above. Apply an AG fault as described in Step 6 above, except with a current of 2 Amp at anangle of 75° lagging the fault voltage. The relay should not trip.

Apply rated dc voltage to terminals TB4-5(+) and TB4-6(-). Again apply an AG fault with a cur-rent of 2 Amp at an angle of 75° lagging the fault voltage. The relay should trip and a review ofthe target should show “CIF Trip” “Yes”. Remove the voltage from TB4-5 and TB4-6. Changethe setting of “CIF Trip” from “Yes” to “No”.

5.1.6 Input Transformer (Ip) Check

STEP 10

Change the following settings using the procedure in Step 3 above.

“Zone 1Ø” = “Disabled” (Zone 1 phase distance setting)“Zone 1G” = “Disabled” (Zone 1 ground distance setting)“Dir Type” = “Dual Polariz.” (Directional overcurrent polarization choice setting)“GB Type” = “CO-8” (Overcurrent ground backup curve family setting)“GBPickup” = “0.5 Amps” (Overcurrent ground backup pickup setting)“GBTCurve” = “24” (Overcurrent ground backup curve selection setting)“GB Dir” = “YES” (Overcurrent ground backup directional choice setting)

Since the “GB Dir” = “YES”, the Ground Backup logic is directional, torque controlled and issupervised by Forward Directional Overcurrent Ground (FDOG) logic. In order to test the direc-tional logic, 3Ø voltages must be applied for correct directional reference. With no voltage ap-plied or if the setting of Loss -of-Potential Block (“LOP Blk”) is “Yes” and at least one inputvoltage is zero volts, GB will be non-directional regardless of the GB Dir setting.

This test is to verify the dual polarizing or fourth current transformer input (Ip). For a dual polar-izing ground directional unit test, connect the test circuit shown in Figure 5-7. Apply IP = 1.0AÐ-90° to terminals FT-13 (+) and FT-12 (-), and apply a balanced 3-phase voltage (Va = Vb = Vc= 70 Vac). Apply IA= 4A to terminals FT-15 (+) and FT-16 (-) to the system under test. Vary theangle of IA relative to Ip and observe tripping at all of the following angles of IA:

• All angles between -3° and -177°


118

• Or -90° ± 87°, where -90° could be referred to as the maximum torque angle

When the relay trips, remove the fault current. OTHER will light. The LCD display will indicatethe fault distance. Using the RAISE and LOWER push-buttons the complete fault record can bereviewed. See Table 4-3 for a description of the displayed fault data.


Fault Type – “FLT Type” “AG”Targets – “GB Trip” “Yes”Fault Voltages (VA, VB, VC, 3V0) and Currents (IA, IB, IC, IP)

Using the same test connection, as above, the system should not trip at any of the following an-gles of IA:

• All angles between +3° and +177°

• Or +90° ± 87°, where +90° could be referred to as the zero torque angle

5.1.7 Output Contact and Input Circuit Verification Test

STEP 11

The purpose of this test is to check the hardware connections, output relay contact operation,and input circuit verification.

To perform these tests, jumper #5 (JP5) on the microprocessor module, must be in place. (Referto paragraph entitled “Acceptance Test” at the beginning of this chapter for details.) Jumper #3(JP3) is a spare jumper which is moved to the JP5 position for this test. Upon test completion,if front panel output contact operation is not desired, remove JP5 and return it to the JP3 posi-tion.

Press the SELECT push-button and scroll to the display to “TEST” mode. The display shouldread “STATUS” “0” indicating the self-checking/startup/initialization routine was completedsuccessfully and the system is continuously passing the self-checking routine. Press the RAISE

push-button and scroll to contact output to be tested. All contact outputs can be tested. See the“CONNECTION SPECIFICATION CHART” in Section 4.3 and “Relay Output Test” in Section4.4.2.1 for contact listing and terminal references.

After scrolling to the contact output to be tested, for example “Trip” “Relay”, pressing the EN-TER push-button will cause the trip relay to operate and hence the trip contacts to close. A sim-ilar procedure is used to test any contact output.

NOTE: Testing of the trip contacts generates a target which is reported as simply“Test” in the display. Trip contact testing is the only contact test which gener-ates a target.

In the “TEST” mode verification of the LEDs functioning is accomplished by scrolling to the“LEDs” “Protection” display and pressing the ENTER push-button. The protection LEDs willlight in the following sequence and remain lit while the ENTER push-button is depressed:

1. Pilot (REL 302 only) 6. BG2. Zone 1 7. CG

I.L. 40-386.1

119

3. Zone 2 8. MØ4. Zone 3 9. OTHER5. AG

The following inputs can be tested, in the “TEST” mode, By applying voltage to each input andobserving the “Inputs” display. Scroll to the “Inputs” display, apply rated voltage and as eachinput is energized, the associated display segment changes from “–” to “|”.

This completes the REL 301 and REL 302 (non-pilot) Acceptance Test.

5. 2. PILOT ACCEPTANCE TESTS (FOR REL 302 ONLY)

5.2.1 Non-Pilot Acceptance Tests for REL 301/302

Perform the acceptance test procedures in Section 5.1 if not previously completed. These testsare valid tests of hardware and firmware performance for either REL 301 or REL 302.

5.2.2 Input Opto-Coupler Check

STEP 12Pilot Enable (PLT ENA)

In Step 3, Section 5.1, the settings from Table 5-5 should have been loaded for Non-Pilot Ac-ceptance Tests. Change the following settings using the procedure in Step 4 above:

“Pilot” = “YES” (Enable pilot logic)“SystType” = “Blocking” (Pilot system selection setting)“Pilot Ø” = “4.5 Ohms” (Pilot phase distance reach setting)“Pilot G” = “4.5 Ohms” (Pilot ground distance reach setting)“Dir Type” = “Zero sequence” (Directional overcurrent polarization choice setting)“GB Type” = “Disabled” (Overcurrent ground backup curve family setting)

Test Using Blocking System

Apply an AG fault as described in Step 6 above. The REL 302 should not trip.

Apply rated dc voltage to terminals TB4-9(+) and TB4-10(-). Again apply an AG fault as de-scribed in Step 6 above. When the relay trips, remove the fault current. PILOT and AG LED’swill light. The LCD display will switch to the “L-FLT” mode and fault distance will be displayed.Using the RAISE and LOWER push-buttons the complete fault record can be reviewed. See Table4-3 for a description of the displayed fault data quantities.

Input Under Test Display

“52a” |- - - - -

“52b” - | - - - -

“EXT RESET” - - | - - -

“PLT ENA” (Pilot Enable, REL 302 only) - - - | - -

“RCVR1” (Receiver 1, REL 302 only) - - - - | -

“RCVR2” (Receiver 2, REL 302 only) - - - - - |


120


Fault Type — “FLT Type” “AG”Targets — “Pilot G” “YES”Fault Voltages (VA, VB, VC, 3V0) and Currents (IA, IB, IC, 3I0)

Pressing the front panel RESET push-button will cause the LCD display to switch to the“METER” display and the LEDs will stop flashing.

STEP 13Receiver Inputs 1 and 2

Apply rated dc voltage to terminals TB4-9(+) and TB4-10(-) for tests a and b below.

a. Blocking System Test

Apply an AG fault as described in Step 6. The REL 302 should trip. When the relay trips,remove the fault current. PILOT and AG LEDs will light. The LCD display will switch to the“L-FLT” mode and fault distance will be displayed. Using the RAISE and LOWER push-but-tons the complete fault record can be reviewed. See Table 4-2 for a description of the dis-played fault data quantities.


Fault Type — “FLT Type” “AG”Targets — “Pilot G” “YES”Fault Voltages (VA, VB, VC, 3V0) and Currents (IA, IB, IC, 3I0)


Applying rated dc voltage to terminals TB4-11(+) and TB4-12(-) simulates the receipt of apilot blocking signal. Again apply an AG fault as described in Step 6. The REL 302 shouldnot trip. Remove voltage from terminals TB4-11 and TB4-12.

Receipt of the pilot signal can also be simulated from the front panel. Using the procedureoutlined in Step 5, press the SELECT push-button until the “TEST” mode is selected. Dis-played is the result of the self-test routine which should show a normal status, “Status” “0”.

Pressing the RAISE push-button, scroll to “Rx1” display. Pressing the ENTER push-buttonsimulates the receipt of the blocking signal. While depressing the ENTER push-button, againapply an AG fault. The REL 302 should not trip.

b. Permissive Overreach and Underreach Transfer Trip (POTT, PUTT) System Test

Change the following setting using the procedure in Step 3.

“SystType”= “POTT” (Pilot system selection setting)

Apply an AG fault as described in Step 6. The REL 302 should not trip.

Applying rated dc voltage to terminals TB4-11(+) and TB4-12(-) simulates the receipt of apermissive signal. Again apply an AG fault as described in Step 6. The REL 302 should trip.When the relay trips, remove the fault current. PILOT and AG LEDs will light. The LCD dis-play will switch to the “L-FLT” mode and fault distance will be displayed. Using the RAISE

I.L. 40-386.1

121

and LOWER push-buttons the complete fault record can be reviewed. See Table 4-3 for adescription of the displayed fault data quantities.

The significant quantities to review are”

Fault Type — “FLT Type” “AG”Targets — “Pilot G” “YES”Fault Voltages (VA, VB, VC, 3V0) and Currents (IA, IB, IC, IP)


Receipt of the pilot signal can be simulated from the front panel as in Part a above. Usingthe procedure outlined in Step 5, press the SELECT push-button until the “TEST” mode isselected. Displayed is the result of the self-test routine which should show a normal status,“Status” “0”.

Pressing the RAISE push-button, scroll to “Rx1” display. Pressing the ENTER push-buttonsimulates the receipt of the permissive signal. While depressing the ENTER push-button,again apply an AG fault. The REL 302 should trip as in the test above as though voltage isapplied to the Receiver 1 input.

c. Repeat the tests in Part b. Above except using the Receiver 2 input by applying rated dcvoltage to terminals TB4-13(+) and TB4-14(-). In the front panel test substitute “Rx2”.

This completes the REL 302 Pilot Acceptance Test.

5. 3. MAINTENANCE PROCEDURES

NOTE: It is NOT recommended to perform any type of invasive periodic maintenancetest (requiring relay disassembly).

5.3.1 Periodic Maintenance Tests

5.3.1.1 Using Remote or Local Data Communication

• Read Metering Values

• Read Diagnostic Information

• Monitor Relay Failure Indication

• Remotely test Output Relay (Trip, Close, etc.)

• Check for Failure Alarm via annunciator or network

• Change real-time clock battery. (See Figure 5-3 for location.) Use a lithium type battery suchas Ray O’ Vac #BR2016.

5.3.1.2 Using Man-Machine Interface

• Use the front display, and push-buttons to manually perform the tests described in Section5.3.1.1 above.

5.3.1.3 Routine Visual Inspection

With the exception of routine visual inspection, the REL 301/302 relay assembly should bemaintenance free for one year. A program of routine visual inspection should include:

• Condition of cabinet or other housing

• Tightness of mounting hardware


122

• Proper seating of subassemblies

• Condition of external wiring

• Appearance of printed circuit boards and components

• Signs of overheating in equipment

5.3.1.4 Perform the Acceptance Test

Performing this test is optional if all other test results are acceptable.

5. 4. CALIBRATION

5.4.1 Pre-Calibration

NOTE: When the REL301/302 is being calibrated, move the jumper from JMP3 to JMP6position on the Microprocessor Module. After calibration, replace the jumperback to the original JMP3 position.

Three trimpots (P17, P16, P15) are used to calibrate the A/D converter; a variable capacitor (C6)is used for clock calibration (see Figure 5-1and 5-3). The REL301/302 relay has been properlyadjusted at the factory; adjustments by the user are not required. The following Factory calibra-tion procedure is for reference only.

1) Turn “OFF” all Vac and Vdc power.

2) Remove the cover and front panel by using a screw driver.

3) Connect together all terminals FT-1, 2, 3, 4, 12-19 through an external mating connector.

4) On the microprocessor module, move jumper from position JP3 to JP6 (see Figure 5-3).

5) On input/filter module, remove U6 (Sample/Hold device) from its socket.

6) Connect a digital voltmeter, with at least 5 digit accuracy, to TP3, and TP2 (common) onthe input/filter module.

7) Using a battery and potentiometer, connect the adjustable voltage to TP1, and commonto TP2 on the input/filter module. Apply voltage per steps 11 and 12 below.

8) Apply a rated dc voltage across FT-20 and FT-11. Turn “ON” the dc power source.

9) On the front panel, depress the SELECT push-button until the TEST mode is indicated.

5.4.2 A/D Calibration

10) Raise the Function field, on LCD display to A/D CAL mode. The value field display showsthe average Hex value of the analog input over one cycle.

11) Set the Voltmeter input to -4.99878 Vdc. Adjust Pot P16 until the Value display readsC009.

12) Set the voltmeter input to +4.99634 Vdc. Adjust Pot 17 until the Value display reds 3FF4.

13) Turn “OFF” the dc power supply.

14) Remove the battery voltage from TP1 and TP2.

15) Remove the digital voltmeter.

I.L. 40-386.1

123

16) Replace U6 in its socket.

17) Turn “ON” the dc power supply and adjust Pot P15 until the Value display reads 0 or FFFFHex.

5.4.3 Real-Time Clock Calibration on Microprocessor Module

18) Connect a precision period counter instrument to TP1, on the microprocessor moduleand TP7 (common) on the input/filter module.

19) On the microprocessor module, adjust variable capacitor (C6) and read the period ofpulses at TP1. It should be 1.000000 second (± 0.000002).

20) Turn “OFF” the dc power supply.

21) Remove the power leads and external connector.

22) On the microprocessor module, move jumper from position JP6 to JP3 and replace frontpanel with six mounting screws.


124

Fig

ure

5-1:

Filt

er (

Inpu

t) M

odul

e

1612

C34

She

et 3

of 3

Sub

2

52a

52b

EXTRESET

PILOT

RCVR

RCVR

SYNCCHECKREFERENCE2

1

ENABLE

Not Used

220/

250

48/

125

15/2

0

220/

250

48/

125

15/

220/

250

48/

125

20

15/2

0

15/

220/25048/125

20

15/

220/25048/125

20

220/250

15/20

48/125

*

*

*

*

*

*

* Inputs are in Volts dc

Common for clock calibration

Sample/Hold Device

Test Points for A/DCalibration

Trim Pots for A/DCalibration

I.L. 40-386.1

125

Fig

ure

5-2:

P

ower

Sup

ply/

Out

put M

odul

e

JMP1

NO NC

JMP2

NO NC

JMP5

NO NC

JMP4

NO NC

JMP3

NO NC

JMP6

NC NO

JMP

7

NC NO

CARRIERSTOP

CARRIERSEND

OC 4

OC 3

AL - 1

AL - 2

OC 2

1612

C68

She

et 4

of 4

Sub

4


126

Figure 5-3: Microprocessor Module

JP6

JP5

JP3

JP4

Clock Battery

1613C55Sheet 3 of 3

Sub 6

Variable Capacitor for ClockCalibration

I.L. 40-386.1

127

Figure 5-4: Test Connection for AØ - Ground Test

+

-

Va

Vb

Vc

If

+

-

+

-

+

-

REL 301/302

(Front View)

Rated dc Voltage (+)

(-)(Check Nameplate)

❋ Install this jumper if dual polarizing not used

❋

1

2

3

4

5

6

7

10

9

8

20

19

18

17

16

15

14

11

12

13

INS

TR

UC

TIO

N M

AN

UA

L R

EL

301/302

128

Figure 5-5: Test Connection for BØ-Ground Test

+

-

Va

Vb

Vc

If

+

-

+

-

+

-

REL 301/302(Front View)



❋


1

2

3

4

5

6

7

10

9

8

20

19

18

17

16

15

14

11

12

13

I.L. 40-386.1

129

Figure 5-6: Test Connection for CØ-Ground Test

+

-

Va

Vb

Vc

If

+

-

+

-

+

-





❋

1

2

3

4

5

6

7

10

9

8

20

19

18

17

16

15

14

11

12

13

INS

TR

UC

TIO

N M

AN

UA

L R

EL

301/302

130

Figure 5-7: Test Connection for AØ-Ground Test (Dual Polarizing)

+

-

Va

Vb

Vc

If

+

-

+

-

+

-




Ip+

-

1

2

3

4

5

6

7

10

9

8

20

19

18

17

16

15

14

11

12

13

I.L. 40-386.1

131

Table 5-4: REL 301 SETTINGS (NON-PILOT SYSTEM)

(As Displayed on Front Panel LCD)

VERSION X.XXOSC Data TripFLT Data TripCT Ratio 1000VT Ratio 2000Freq 60 HzCT Type 5 ampsRead Out Secondary UnitsX/Dist 0.500 W/KmDist Unit KilometersRI Type No RIFast RI Z1/Inst IZone 2 RI NOZone 3 RI NOSys Type Non PilotZone1 ø 4.50 OhmsZone1 G 4.50 OhmsT1 Timer 0 CyclesZone2 ø DisabledT2Ø Type Definite TimeT2Ø Time 1.00 secZone2 G DisabledT2G Type Definite TimeT2G Time 1.50 secZone3 ø DisabledT3 ø 2.00 secZone3 G DisabledT3 G 2.50 sec

Zone 3 Forward DirAng Pos. 75°Ang Zero 75°Z0L/Z1L 3.0Low V 60 VoltsLow Iø 0.50 ampsIM 0.50 amps3IOs 0.50 amps3IOm 0.50 ampsInst. ø DisabledInst. G DisabledOS Block NOOSOT 4000 secOS Inner 15.00 OhmsOS Outer 15.00 OhmsDir Type Zero SequenceGB Type DisabledGB Pickup 0.50 ampsGBT Curve 24GB Dir YESCIF Trip NOLL Trip NOLOP Blk NO LOI Blk NOTrip Alm Seal-inRem. Set Remote AllowedSet Time NO

NOTE: This REL 301 settings table is for 60 Hz and 5A ct systems. For 1A ct, change Zone1 Ø,Zone1 G, Zone2 Ø, Zone2 G, Zone3 Ø, Zone3 G, OS Inner, OS Outer by multiplying a factorof 5, and all current values mentioned in the text should be multiplied by a factor of 0.02.


132

Table 5-5: REL 302 SETTINGS (PILOT SYSTEM)

(As Displayed on Front Panel LCD)

VERSION X.XXOSC Data TripFLT Data TripCT Ratio 1000VT Ratio 2000Freq 60 HzCT Type 5 ampsRead Out Secondary UnitsX/Dist 0.500 W/KmDist Unit KilometersRI Type No RIFast RI Z1/Inst IZone2 RI NOZone3 RI NORemBF RB NOPilot NOSystType Non-PilotFDOG Time BlockedWeakfeed NO3-Term NOBlk Time 0 msecPilot ø DisabledPilot G DisabledZone1 ø 4.50 OhmsZone1 G 4.50 OhmsT1 Timer 0 CyclesZone2 ø DisabledT2 ø Type Definite TimeT2 ø Time 1.00 secZone2 G DisabledT2G Type Definite TimeT2G Time 1.50 secZone3 ø Disabled

T3 ø 2.00 secZone3 G DisabledT3 G 2.50 secZone 3 Forward DirAng Pos. 75°Ang Zero 75°Z0L/Z1L 3.0Low V 60 VoltsLow Iø 0.50 ampsIM 0.50 amps3IOs 0.50 amps3IOm 0.50 ampsInst. ø DisabledInst. G DisabledOS Block NOOSOT 4000 secOS Inner 15.00 OhmsOS Outer 15.00 OhmsDir Type Zero SequenceGB Type DisabledGB Pickup 0.50 ampsGBT Curve 24GB Dir YESCIF Trip NOLL Trip NOLOP Blk NO LOI Blk NOTrip Alm Seal-inRem. Set Remote AllowedSet Time NO

NOTE: This REL 301 settings table is for 60 Hz and 5A ct systems. For 1A ct, change Zone1 Ø,Zone1 G, Zone2 Ø, Zone2 G, Zone3 Ø, Zone3 G, OS Inner, OS Outer by multiplying a factorof 5, and all current values mentioned in the text should be multiplied by a factor of 0.02.

I.L. 40-386.1

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Table 5-6: REL 301/302 Reference Drawings

Drawing Name Drawing Number (Sheet Numbers)

General Drawing 2678F11 (1,2,3,4)

Filter Module Schematic 1612C33 (1,2)

Filter Module Assembly 1612C34 (1,2,3)

Backplane Module Schematic 1357C85

Backplane Module Assembly 1612C53 (1,2,3)

Power Supply Module Schematic 1357D14

Power Supply Module Assembly 1612C68 (1,2,3,4)

CT Module Schematic 1503B32

CT Module Assembly 1612C79 (1,2)

VT Module Schematic 1503B33

VT Module Assembly 1612C80(1,2)

Microprocessor Module Schematic 1357D38 (1,2)

Microprocessor Module Assembly 1613C55 (1,2,3)

Display Module (MMI) Schematic 1613C76

Display Module (MMI) Assembly 1613C69 (1,2)

Reclosing Module Schematic 1614C17 (1,2,3,4)

Reclosing Module Assembly 1614C19 (1,2)

Firmware Upgrade Procedure L - 682A34


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RESERVED FOR NOTES

REL301/302 Firmware Version 1.23 (08/19/03) …€¦ · The Pilot will not trip with RX=0 if the...

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Transcript of REL301/302 Firmware Version 1.23 (08/19/03) …€¦ · The Pilot will not trip with RX=0 if the...