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MSP-REF Technical Manual

01/09/03 Page 0 Issue 2

MSP-REFRestricted Earth Fault Relay

P&B EngineeringBelle Vue WorksBoundary StreetManchesterM12 5NGTel: 0161 230 6363Fax: 0161 230 6464Internet Address http://www.pbeng.co.ukE-mail [email protected]


01/09/03 Page ii Issue 2

Contents

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

2. APPLICATION ..................................................................................................................................................................2

3. FEATURES AND CHARACTERISTICS........................................................................................................................2

4. DESIGN...............................................................................................................................................................................3

4.1 APPLICATION DIAGRAMS.................................................................................................................................................34.1.1 Analogue input circuits............................................................................................................................................34.1.2 Output relays ...........................................................................................................................................................34.1.3 Remote data communication ...................................................................................................................................4

5. FRONT PANEL..................................................................................................................................................................4

5.1 DISPLAY ..........................................................................................................................................................................45.2. BUTTONS........................................................................................................................................................................55.3. LED INDICATORS. ..........................................................................................................................................................6

6. WORKING PRINCIPLES ................................................................................................................................................6

6.1 ANALOGUE CIRCUITS.......................................................................................................................................................66.2 DIGITAL CIRCUITS............................................................................................................................................................66.3. POWER SUPPLY...............................................................................................................................................................66.4. OPERATION OF HIGH IMPEDANCE DIFFERENTIAL PROTECTION.......................................................................................76.5. REQUIREMENTS FOR CURRENT TRANSFORMERS. ...........................................................................................................7

7. OPERATION AND SETTING..........................................................................................................................................8

7.1 LAYOUT OF THE CONTROL ELEMENTS..............................................................................................................................87.2. ACCESSING THE MSP-REF MENU SYSTEM....................................................................................................................87.3. MENU TREE ...................................................................................................................................................................97.4. RELAY SETTING PRINCIPLES............................................................................................................................................9

7.4.1. Communication Settings. ........................................................................................................................................97.4.2. System/Unit Settings. ............................................................................................................................................107.4.3. Protection Settings................................................................................................................................................107.4.4. Auxiliary Relay Settings. ......................................................................................................................................127.4.5. Contrast Settings. .................................................................................................................................................127.4.6. Settings Summary .................................................................................................................................................13

8. DISPLAYED DATA.........................................................................................................................................................14

8.1 INDICATION OF MEASURED VALUES ...............................................................................................................................148.2 INDICATION OF FAULT DATA ..........................................................................................................................................14


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9. RELAY CASE ..................................................................................................................................................................14

9.1 INDIVIDUAL CASE ..........................................................................................................................................................149.2 RACK MOUNTING...........................................................................................................................................................149.3 TERMINAL CONNECTIONS ..............................................................................................................................................14

10. TEST AND MAINTENANCE.......................................................................................................................................14

11. TECHNICAL DATA MSP-REF. ..................................................................................................................................15

11.1. MEASURING INPUT CIRCUITS......................................................................................................................................1511.2. AUXILIARY POWER SUPPLY.........................................................................................................................................1511.3. COMMON DATA. .........................................................................................................................................................1511.4. SETTING RANGES, STEPS AND ACCURACIES. ..............................................................................................................1611.5. OUTPUT CONTACT RATINGS. .......................................................................................................................................1611.6. SYSTEM DATA. ...........................................................................................................................................................1611.7. TYPE TESTS................................................................................................................................................................1711.8. HOUSING. ...................................................................................................................................................................20

12. ORDER FORM ..............................................................................................................................................................22


01/09/03 Page 1 Issue 2

1. Introduction

The application of powerful microprocessors opens a new chapter for power system protectiverelaying. The digital processing of measured values and the ability to perform complex arithmeticand logic operations, give digital protection relays significant performance and flexibilityimprovements over their traditional analogue counterparts. Additional advantages - very smallpower consumption, adaptability, self-supervision, fault diagnosis through fault data recording,smaller physical construction and selectable relay characteristics - all combine to allow theimplementation of accurate and highly reliable protection schemes at a significantly reducedfinancial burden.

The development of microprocessor based protective relays and their introduction into the markethas been stimulated by the recent trend to replace analogue with digital equipment. This moderntrend has prompted the development of a new P&B protective relay family - the MSP relay series.This comprehensive family of protection relays can satisfy the demands of even the most complexprotection schemes:

MSP - Overcurrent or Earth Fault Relays (Independent time/I.D.M.T)MSP-REF- Restricted Earth Fault (or Ground) RelayMSP- V - Voltage Protection RelaysMRI - Overcurrent Relay (Independent time/I.D.M.T + earth + directional facilities)MRI-V - Voltage Dependent Overcurrent RelayMREF - Restricted Earth Fault RelayMRAR - Auto-Reclosing RelayMRMF - Mains Failure RelayMRVT - Voltage ProtectionMRFT - Frequency ProtectionMROS - Vector SurgeMRNS - Negative Sequence RelayMRRP - Power RelayMRCS - Check Synchronising RelayMRFF - Field Failure RelayMRDG - Differential Relay

The superiority of digital protective relaying over traditional analogue devices, as embodied by theMSP-REF relay family, is summarized by the following features:

•••• Integration of many protective functions in a single compact case•••• High accuracy owing to digital processing•••• Digital relay setting with very wide setting ranges and fine setting steps•••• Comfortable setting procedure through extensive user - relay dialogue•••• Measured values and fault data indication by means of alpha-numeric display•••• Data exchange with DCS/SCADA by means of RS485 interface•••• Operational reliability through self-supervision

The digital overcurrent and earth fault relay MRI, was designed as a universal overcurrentrelay for applications in medium voltage networks. A similar, but simplified version, theMIRI, with reduced functions and without display, is also available.


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Similarly for protection against undervoltage, overvoltage and neutral voltage displacement, areduced function non-display relay, the MIRV is available.

To complement the MR series, a range of Auxiliary, Timing and Tripping devices are alsoavailable.

The MSP range of relays were added to create a new series of single pole, competitive overcurrentor voltage protection relays. They have the added feature of a large LCD Display, enabling greaterdisplay of data.

2. Application

The MSP-REF digital overcurrent relay, is a universal protection device for high, medium andlow voltage networks. It is aimed primarily at high impedance differential schemes such asrestricted earth fault and generator differential protection.

In this type of protection scheme, based on circulating current measurement, heavy through faultcurrents during a fault condition can cause current transformers to approach or exceed theirsaturation level and allow sufficient unbalance current to operate the relay. This is due to theasymmetrical current of extreme magnitude which has dissimilar effects on seemingly identicalCT's.

In order to ensure stability under these circumstances, it is usual practice to employ a highimpedance differential scheme, the stability of which is achieved through careful selection of CT's,stabilising resistors, settings and non-linear resistors.

For further details of the application of the relay, please refer to technical note MR901.

3. Features and characteristics•••• Single phase current measurement•••• Stabilisation by means of a resistor in series with the current relay in differential circuit•••• The harmonics produced by current transformer saturation should be rejected by a series

resonant circuit.•••• The total impedance of the relay should be low enough to prevent the current

transformers developing high voltages during maximum internal faults•••• The current setting range of 5% - 1000% In (in steps 1% x In)•••• The time delay is not selectable, but for currents of 1 to 2 x Is there should be a small

time delay of about 40 mS so that no maloperation occurs due to a heavy through fault.• Complete digital sampling and processing of the measured values• High quality filtering of measured values using both 8th order filters and software

filtering to suppress high frequency harmonics and d.c component induced byfaults or system operations

• Wide setting ranges with fine setting steps• Continuous self-supervision of software and hardware• Unauthorized user access control through user defined password protection• Numerical display of setting values, actual measured values and their

active/reactive components and memorized fault data etc, with contrast adjustment.• Serial data communication facilities via RS485• Wide voltage range for DC or AC power supply


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4. Design

4.1 Application Diagrams

POWER

SUPPLY

1 2Supply

CASE

4External Reset

L

AUXILIARY RELAY 1

12

16

14

+

7 5 9

Gnd-RS485

MSP-REF

EARTH3

(TRIP A)

AUXILIARY RELAY 2

6

10

8(PROGRAMMABLE)

AUXILIARY RELAY 3

11

15

13(PROGRAMMABLE)

27

28RS

4.1.1 Analogue input circuits.

The constantly monitored current is galvanically isolated, rectified, filtered, fed to an analogue todigital converter and sampled by the processor.

4.1.2 Output relays

The MSP-REF has three output relays, with single pole change-over contacts as detailed in theprevious diagrams. Relay 1 is set to Trip A. The remaining two relays can be programmed withany of the following:

options:-• Trip A.• Trip A Fail Safe.• Trip B.• Trip C.• Warn.• Alarm Fail Safe.• Self Supervision.

See Section 7.4.4. for more details.


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4.1.3 Remote data communication

The MSP-REF has an RS485 interface for remote data communication with a control centre. Theunit provides the following information:

• Measured phase fault current values• Status signals• Self supervision alarm signal• Relay settings• Fault Status

5. Front panel

The front panel of the MSP-REF comprises of thefollowing operation and indication elements:

• Alphanumeric back lit display (2 x 16 Digits)• 4 push buttons for setting and other operations• 3 Tri colour LEDs for power and health status.

5.1 Display

The MSP-REF is equipped with a 2 line, 16 character per line display. The display is used for thefollowing functions:

• Viewing and changing of setting parameters• Viewing of Data Parameters• Trip and Alarm Messages.

As the display is able to generate text messages. Multiple buttons and LEDs are not required. TheMSP-REF only requires four buttons which are used inconjuction with information on the displayto access and enter data using menus.

You are also able to change the contrast on the display.


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5.2. Buttons.

MSP-REF has a 2 line 16 character display which allows for the four buttons to have multipleapplications. The four buttons comprise of:-

• Value Up/Scroll Up (UP)• Value Down/Scroll Down (DOWN)• Enter/Yes (S1)• Exit/No (S2)

The bottom left and right corners are accessed by using the S1 and S2 buttons. They will dowhatever appears in that area of the display.

For example, with the display as shown above:

UP and DOWN will scroll the user up and down the setting options.

S1 which is below the left hand corner of the display corresponds to the "tick" and will thereforeenter the "Protection Settings". This button would also, in other screens, be used to enter a value.

S2, which is below the right hand corner of the display, corresponds to the "cross" and willtherefore exit this screen. This button would also be used to abandon a setting value withoutstoring it.

For more details see Section 7.


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5.3. LED Indicators.

On the front of the MSP-REF are two Tri color LEDs which indicate the following information:-

LED Colour Left LED - Relay Status Right LED - Fault StatusGreen Power Healthy

Yellow N/A AlarmRed Irf Trip

6. Working principles

6.1 Analogue circuits

The incoming voltages from the external transformers are converted to signal levels in proportionto the voltages, via the internal input transducers and shunt resistors. The noise signals caused byinductive and capacitive coupling are suppressed by an active filter circuit and an 8th orderswitched capacitive filter. The analogue signals are fed to the A to D converter of the micro-processor and transformed to digital signals through sample-hold circuits. The analogue signalsare sampled at a frequency of 2 kHz, namely a sampling rate of 0.5 mS for every measuredquantity.

6.2 Digital circuits

The essential component of the MSP-REF relay is a powerful micro-controller. All of theoperations, from the analogue digital conversion to the relay trip decision, are carried out by themicro-controller. The relay program, located in EPROM, allows the CPU of the micro-controllerto calculate the phase voltage in order to detect a possible fault.

The digitised low level signals are processed within the software to give an actual value. Theactual calculated voltage values are compared with the relay settings. When a voltage is over (orunder) the unit starts the corresponding time delay calculation. When the set time delay haselapsed, a trip signal is given.

The relay setting values for all parameters are stored in EEPROM, so that the actual relay settingscannot be lost, even in the event of auxiliary supply interruption. The micro-processor issupervised through a built in "Watch-dog" timer. Should a failure occur the watch-dog timer resetsthe micro-processor and gives an alarm signal via the self supervision output relay.

6.3. Power supply.

Each relay can be operated from a wide range of power supplies:

Vaux = 80 - 265V AC/DC


01/09/03 Page 7 Issue 2

6.4. Operation of High Impedance Differential Protection.

The relay is connected in the differential circuit across the CT's as shown below.

In the case of a through fault condition, both CT's will reflect the fault current into the secondary.If the CT magnetising curves, internal impedance’s (Rs) and lead resistances (RL) are similar forboth the CT's, the voltage Vs will be approximately zero.

During saturationis short circuit

Rs RL RL Rs

Rsr Vs

R

Z Z

Protected ObjectIF IF

Equivalent Circuit to describe the working principles of the MSP-REF

However, if the fault current passes only through one CT (in zone fault) then the second CT willappear as an open circuit (magnetising current only), and Vs will be of sufficient magnitude tooperate the relay through Rsr.

During severe fault conditions, this voltage may rise to an extremely high value. Thus, a voltagedependent non-linear resistor may be required to limit this voltage.

In practice if one CT becomes saturated first, during a through fault, inadvertent operation mayoccur. In order to prevent this a stabilising resistor Rsr is fitted.

The relay input circuit is tuned to the network supply frequency (50/60 Hz) by means of a resonantcircuit and harmonics produced by the CT's can be effectively rejected.

6.5. Requirements for Current Transformers.

In order to ensure the correct operation of the MSP-REF protection relay, the characteristic of theCT must be selected to suit its application.

In general the CT's must be Class X, all of the same ratio and similar secondary resistance. Theyshould have a knee point of at least twice the setting voltage.

or Vkn 2 Vset= ×


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7. Operation and setting

7.1 Layout of the control elements

All control elements required for the operation and adjustment of the MSP-REF are located onthe front panel as shown in Figure 5.1. They are divided according to function into the followinggroups:

• Alphanumeric Display: Indication of parameter set values, actual measured values andrecorded fault data.

• Push Buttons: Selection of parameter to be adjusted, quantity to be measured andadjustment of parameter values. Where each of the four buttons hasmore than one action;

<S1> This buton located in the top left of the button array is used todo whatever appears in the bottom left hand corner of thedisplay. This can be storing a value, entering a screen etc.

<UP> This button, located in the middle top of the button array, hastwo actions:-

1. Increment of the setting values for the parameter selected.2. Scrolling through the menu system.

<DOWN> This button, located in the middle bottom of the button array,has two actions:-

1.Increment of the setting values for the parameter selected.2. Scrolling through the menu system.

<S2> This buton located in the top right of the button array is used todo whatever appears in the bottom right hand corner of thedisplay. This can be reseting faults, exiting a screen etc.

7.2. Accessing the MSP-REF Menu System.

The MSP-REF menu system is accessed using the <UP> and <DOWN> buttons to scroll throughthe options and the <S1> and <S2> buttons to select the options.

Once a value screen is shown the <UP> and <DOWN> buttons are used to increase or decreasethe chosen value. The <S1> and <S2> are then used to store the value.

The full menu system can be seen in the menu tree at Section 7.3.


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7.3. Menu Tree

7.4. Relay setting principles

The setting menu is protected by a password to ensure only authorised changes to the relaysettings occur. If the password is enabled then the user must enter the password to enter thesettings. The following are the relay parameters that can be set by the user, dependent upon relaytype;

7.4.1. Communication Settings.

P&B Engineering has developed Network Gold, our own specific protocol for use with ourRelays, which permits full use of the vast amount of data available from each device. The ASCIIbased protocol has message lengths limited to 9 bytes and with the use of a 16 bit CCITTapproved CRC gives complete data integrity.

Baud Rate.This value determines the speed at which the relay communicates through its RS485 port. It can beset to 9600 Baud or 19200 Baud with a default setting of 9600.

Link Address.This setting range 0 to 32, with a default setting of 0, identifies the relay to the XCell unit (or anysoftware capable of communicating to a Data highway) to which the RS485 Data Highway of theMSP is connected. It is required to be set if the setting software is to be used. When set to 0 thefeature is turned off.

MAIN

COMMS

RELA YOUTPUT

SYSTEM

S1 = TAKES YOU RIGHT / SAVES2 = TAKES YOU LEFT / RESET

BAUD RATE,LINK ADDRESS

RELAY #3

RELAY #2 TRIP A-C, TRIP A FS,WARN, ALARM FS,SELF SUPERVISION

TRIP LEVEL,

TRIP A-C,ALARM,WARN

PANEL RESET,SERIAL RESET,REMOTE RESET,AUTO RESET

FOR EACH PROTECTION FUNCTION

M S P M E N U S Y S T E M .

= SCROLLS YOU UP THE MENU= SCROLLS YOU DOWN THE MENU

PROTECTION.

PASSWORDMSP PASSWORDSET PASSWORD

DISPLAYSPHASECURRENT& FAULTSTATUS.

S/W Ver.CONTRAST

ADJUSTMENT


01/09/03 Page 10 Issue 2

7.4.2. System/Unit Settings.

Password.The programmable password is required (if enabled) when the user enters the settings menu. If theuser attempts to change a parameter and the password has not been entered then the user is takendirectly to this screen. The password is then entered here and remains valid as long as the relay isswitched on. If the power is switched off the password must be entered into the relay, whenpowered up, to allow the changing of parameters. This also displays the current password, asentered by the user. The password has a default value of 6363.

MSP Password.The user is able to determine whether a password is required to enter the menu screen by settingthis parameter to Enabled or Disabled, with a default setting of Disabled.

Set Password.If the password is disabled or the correct password is entered then the Set Password optionappears. This option enables the user to change the password, from the default password of"6363". The password can be set in the range 0000 to 9999.

7.4.3. Protection Settings.

Trip Level.(Is)

The setting current Is,(range 5 - 1000% In in steps of 1%) and the stabilising resistor Rsr must beselected as;

IsVsRsr

=

where;

VsIn

(Rct 2R Ra)FL≈ × + +

Where;

Vs = Setting VoltageIF = Fault Level in CT Primaryn = CT RatioRct = Resistance of CT secondaryRL = Load ResistanceRa = Additional Resistance due to contacts, connections etc.

With the CT knee point in excess of 2 × Vs

The value of the stabilising resistance is selected so that the relay setting current will fall withinthe setting range (5 - 1000% In)


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If the relay measuring current is higher than the setting value, the relay trips instantaneously withthe operating time approximately <40 mS (this includes the time taken for the output relay tooperate).

Careful selection of Rsr and Is must be made such that excessive voltage is not present for highfault currents.

For further details of the setting of the MSP-REF relay, please refer to technical note MR901 forrestricted earth fault, or MR904 for Bus-Zone protection.

Trip.This setting will determine what trip output is activated once the Trip Level has been exceeded. Ifone of the output relays is set to the corresponding trip it will close when the protection functionhas tripped. The options are Trip A, Trip B and Trip C. This option can also be disabled.

Alarm/Warn.This setting will determine what relay output is activated once the Trip Level has been exceeded.The options are Warn & Alarm, Warn only and Alarm only. If set to Warn then when the TripLevel is exceeded then the Output Relay set to Warn will close. If set to Alarm then when the TripLevel and the Trip Time is exceeded then the Output Relay set to Alarm Fail Safe will open. Thisoption can also be disabled.

Reset.This value determines how the fault can be reset. The option are either:-

Auto Reset. This option, when set to Yes, automatically resets the Function when thesituation that caused the trip has been removed. This can be set to Yes or No with a defaultof No.

Panel-Reset. This option, when set to Yes, allows a reset of a fault to be accomplishedfrom the front panel of the relay. This can be set to Yes or No with a default of No.

Serial-Reset. This option, when set to Yes, allows a reset of a fault to be accomplishedthrough the serial link of the relay. This can be set to Yes or No with a default of No.

Remote-Reset. This option, when set to Yes, allows a reset of a fault to be accomplishedthrough the digital input to the relay. This can be set to Yes or No with a default of No.

It is possible to set the relay such that Panel-Reset, Serial Reset and Remote Reset (or anycombination of the three) are set to yes. This would mean it is possible to have more than one wayof resetting the relay. If it is set to Auto-Reset the relay will reset automatically so therefore it isnot possible to set Panel, Serial and Remote to yes when Auto is set to Yes.


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7.4.4. Auxiliary Relay Settings.

The MSP-REF has three relays, two of which can be programmed. They have the followingdefault Values:

Auxiliary Relay #1 Set to TRIP AAuxiliary Relay #2 Default Alarm FS (Programmable)Auxiliary Relay #3 Default SELF SUPERVISION. (Programmable)

They relays can be programmed as follows:-

Trip A, B, C.This closes the relay when a Protection Function, with the corresponding feature enabled, trips.

Trip A Fail Safe.This opens the relay when Trip A is closed.

Warn.This closes the relay when a Protection Function, with the corresponding feature enabled, is aboutto trip, i.e. its Trip Value has been exceeded and it is counting down to a trip.

Alarm Fail Safe.This opens the relay when a Protection Function, with Alarm enabled, trips.

Self Supervision.This will close the relay when there is an internal fault on the MSP-REF.

7.4.5. Contrast Settings.

The MSP-REF has an LCD display whose contrast can be adjusted. This is done in the initialscreen (that appears on power up before changing to the menu screen.) To get to the Initial Screenpress the UP button when the screen is displaying the Menu Screen. The Initial Screen will thenappear, displaying both the Serial Number and the Software Version.

To adjust the contrast press the left button(S1) to decrease the contrast and the right screen (S2) toincrease the contrast. There are ten steps from the least to the greatest contrast.


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7.4.6. Settings Summary

COMMUNICATION SETTINGS SETTING RANGE DEFAULT

Baud Rate 9600, 19200 9600Link Address. 0 - 32 1

SYSTEM / UNIT SETTINGS

MSP Password Enable/Disable DisableSet Password 0000-9999 6363

AUXILIARY RELAY SETTINGS

Auxiliary Relay #1 Trip A Trip A

Auxiliary Relay #2 Trip A-C, Trip A Fail Safe, Warn, Alam FSAlarm Fail Safe, Self Supervision.

Auxiliary Relay #3 Trip A-C, Trip A Fail Safe, Warn, Self SupervisionAlarm Fail Safe, Self Supervision.

PROTECTION FUNCTION SETTINGS

Trip Setting 5% - 1000% In

PROTECTION FUNCTION OPTIONS.

Function Trip A Trip B Trip C Alarm Warn Auto Panel Serial RemoteReset Reset Reset Reset

Trip N N N N N N N N N

Can be set to N (NO) or Y(YES). Default values are shown.


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8. Displayed Data

8.1 Indication of measured values

The measured phase currents can be viewed on the display during normal service. It can bedisplayed as both a percentage of In and as a percentage value of I/Iset.

8.2 Indication of fault data

Visual indication of faults detected by the relay is given on the display.

9. Relay case

The MSP-REF is delivered in an individual case for flush mounting.

9.1 Individual case

The MSP-REF is supplied in a UK manufactured industry standard drawout case suitable forflush mounting. For case dimension and cut-out, refer to the Technical Data Section.

9.2 Rack mounting

MSP-REF relays may be supplied mounted in 19" racks if specified by the user.

9.3 Terminal connections

The MSP-REF plug in module is supplied in a case which has a very compact plug and socketconnector. The current terminals are equipped with self closing short circuit contacts. Thus theMSP-REF module can be unplugged even with current flowing without endangering personnel.

10. Test and maintenance

Currents may be supplied to the input transformers to test the behaviour of the relay. By switchingon test currents and measuring the tripping time, the whole system can be accurately tested. Aportable test case can be supplied which is suitable for testing the MSP-REF.

All measuring input circuits of the MSP-REF are of solid state design and the relay functions arefully digitized. Thus, the MSP-REF has no particular demand on maintenance.


01/09/03 Page 15 Issue 2

11. Technical Data MSP-REF.

11.1. Measuring Input Circuits.

Rated Data

Rated current, IN 1A or 5A

Burden

@ IN = 1A 0.2 VA@ IN = 5A 0.1 VAIn voltage circuit < 1 VA

Thermal withstand

Half wave 200 x INfor 1 second 80 x INfor 10 seconds 30 x INContinuously 4 x IN

11.2. Auxiliary power supply.

Supply VoltageVaux = 80-265V AC/DCPower ConsumptionQuiescent Approx. 3WOperating Approx. 6W

11.3. Common data.Drop Off/Pick Up ratio >97%Drop Off time 30mSTime Lag error ± 10mSMinimum operating time <40 mSTransient over-reach ≤ 5%

Factors affecting current measurement:

Auxiliary voltage No changes measured

Frequency harmonics in the range 0.9 < f/fN < 1.1 = < 0.20% /HzUp to 20% of the third harmonic = < 0.08% /HzUp to 20% of the fifth harmonic = < 0.07% /Hz

Factors affecting delay times:- No influences could be measured.


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11.4. Setting Ranges, Steps and Accuracies.

Parameter Range Steps AccuracyIE> 5 – 1000% 1% ±5% of settingTrip Time Instantaneous N/A <40mS

11.5. Output contact ratings.

Number of relays = 3Contacts = 1 change over contacts for programmable signal

Maximum breaking capacity250V AC / 1500VA / continuous current 6A

for DC voltage:ohmic L/R = 4ms L/R = 7ms

300 V DC 0.3 A / 90 W 0.2 A / 63 W 0.18 A / 54 W250 V DC 0.4 A / 100 W 0.3 A / 70 W 0.15 A / 40 W110 V DC 0.5 A / 55 W 0.4 A / 40 W 0.2 A / 22 W

60 V DC 0.7 A / 42 W 0.5 A / 30 W 0.3 A / 17 W24 V DC 6 A / 144 W 4.2 A / 100 W 2.5 A / 60 W

Max. rated making current: 64A(IEC65)mechanical life span: 3 × 106 operating cycleselectrical life span: 2 × 105 operating cycles at 220 V AC / 6AContact material Silver Cadmium Oxide (AgCdO)

11.6. System data.

Design standard = IEC 255-4, BS 142Operating temperature range = -20°C to 70°CStorage temperature range = -40°C to 85°CRelative humidity = 93% @ 40°C for 56 days


01/09/03 Page 17 Issue 2

11.7. Type Tests.

F1 Functional Tests Internal DesignSpecifications &IEC60255-6IEC60255-3

Performance in line with Specification &Standards

Climatic Tests

C1 Temperature Dry Cold (Relay operational)

IEC600 68-2-1 -20 deg C , 96 hours

C2 Temperature Dry ColdTransportation & Storage

IEC600 68-2-1 -40 deg C, 96 hours

C3 Temperature Dry Heat (Relay operational)

IEC600 68-2-2 70 deg C, 96 hours

C4 Temperature Dry HeatTransportation & Storage

IEC600 68-2-2 85 deg C, 96 hours

C5 Damp Heat Steady State(Relay operational)

IEC600 68-2-3 93% @ 40 deg C , 56 days

Enclosure

C6 Enclosure IEC 529 front IP52 , rear IP00

Mechanical(Relay operational)

M1 Vibration IEC60255-21-1 Class IVibration response (relay operational)10Hz~150Hz - peak displacement 0.035mmbelow 58/60Hz,0.5g above ,1 sweep cycle ineach axisVibration endurance (relay de-energised)10Hz~150Hz 1g , 20 sweep cycles in eachaxis(160 minutes at 1 octave /min)

M2 Shock & Bump IEC60255-21-1 Class IShock response (relay operational) 5g 11mS 3pulse in each axisShock withstand (relay de-energised) 15g 11mS3 pulses in each axisBump (relay de-energised) 10g 16mS 1000pulses in each axis

M3 Seismic IEC60255-21-1 Class IMethod A single axis sine sweep1Hz~35Hz – below 8/9Hz 3.5mm peakdisplacement horizontal axis, 1.5mm verticalaxisabove 8/9Hz 1g horizontal,0.5g vertical1 sweep cycle in each axis


01/09/03 Page 18 Issue 2

ElectricalE1 Insulation resistance

>100MΩIEC60255-5 500 Vdc , 5 sec between all terminals & case

earth, between terminals of independent circuitsincluding contact circuits and across opencontacts

E2 DC & AC Supply Voltage(Relay operational)

IEC60255-6 Voltage range, upper & lower limit continuouswithstand , ramp up & down over 1 minute

E3 Voltage Dips , ShortInterruptions & Voltagevariations immunity(Relay operational)

IEC60255-11IEC 1000-4-11

3 dips & 3 interruptions at 10 sec intervals ofduration between 10mS and 500mS at zerocrossings & at other points on wavevariation:100% to 40% over 2s,hold for 1s,returnto 100% over 2s

E4 Ripple in dc supply(Relay operational)

IEC60255-11 12% ac ripple

E5 Dielectric Test (Relay de-energised)No breakdown or flashoverTest voltage 45~65HzsinusoidalOr with dc voltage at 1.4x thestated ac values

IEC60255-5 Series C of table 1 2.0 kV 50Hz , 1 minutebetween all terminals & case earth2.0 kV 50Hz , 1 minute between terminals ofindependent circuits including contact circuits.1.0 kV 50Hz , across open contacts , 1 minute

E6 High Voltage Impulse(Relay de-energised)

IEC60255-5 5 kV peak 1.2/50uS,0.5J - 3 positive , 3 negativebetween all terminals to case earthbetween independent circuits

E8 CT input Thermal Withstand 250xIn half wave100xIn for 1 second30 xIn for 10 second4 xIn continuously

E9 Contact performance &endurance tests

IEC60255-14,15IEC60255-23


01/09/03 Page 19 Issue 2

Electromagnetic CompatibilityR1 Electrical fast Transient/Burst

(Relay operational)IEC60255-22-4IEC601000-4-4

Class IV-4.0kv Power supplyClass III -2.0 kV Other inputs1 minute each polarity

R2 Oscillatory Waves1 Mhz Burst(Relay operational)

IEC60255-22-1 Class IIIlongitudinal 2.5 kVpeak , 2sec betweenindependent circuits & case earthtransverse 1.0 kVpeak , 2sec acrossterminals of the same circuit

R3 Electrostatic Discharge(Relay operational )

IEC60255-22-2 Class III15kV air discharge with cover in place , 8 kVcontact with cover removed - 10 discharges ,both polarities at 1 sec intervals

R4 Conducted DisturbanceRF fields(Relay operational)

IEC61000-4-6 0.15 to 80 MhzSeverity Level 10Vrms+sweeps 0.05-0.15MHz & 80-100MHz

R5 Radiated e-m fieldfrom digital portable telephones(Relay operational)

ENV 50204 900 & 1890mhz at 10V/m

R6 Radiated RF e-m field immunity test (Relay operational)

IEC60255-22-3 Class III test method A+sweep 500-1000mhzor IEC 1000-4-3 80-1000mhzseverity 10V/m 80% modulated 1 kHz

R7 Surge Immunity capacitivelycoupled(relay operational)

IEC61000-4-5Class 5Test level 4

short circuit combination wave generator1.2uS/50uS open circuit8uS/20uS short circuit ,+ & - polarityphase shifting 0~360o ac line phase anglerepetition rate 1 per minutePower supply, ct & vt circuits –4kV common mode 2 ohm source2kV differential mode 12 ohm sourceOutput relays 42ohm sourceComms 2 ohm screen to earth only

R8 Power Frequency Magnetic Field(Relay operational)

IEC61000-4-8 1000A/m for 1 sec100A/m for 1 minutein each of 3 axes

R9 Power Frequency Interference oncommunications circuits(Relay operational)

EA TS48-5class 3, Table 2,Appenix A

For circuit length 100-1000 metres (0.1%unbalanced)

R10 Power Frequency interference onother circuits except 50 Hz inputs(Relay operational)

EATS 4805

R11 Pulse Magnetic Field(Relay operational)

IEC 1000-4-9 6.4/16uS , 1000A/m

R14 Conducted & Radiated RFInterference Emission(Relay operational)

EN55022 orEN55011orEN50081-2IEC60255-25

Class A interference limits


01/09/03 Page 20 Issue 2

11.8. Housing.

Throughout the MSP-REF series range a modular housing system has been employed, utilizingthe latest high quality UK manufactured industry standard case components. This approach affordsmaximum flexibility for both the relay scheme designer and the maintenance engineer. The relaymodules are fully withdrawable for ease of maintenance and where applicable incorporateautomatic short-circuiting CT connections to avoid dangerous open circuit CT overvoltages. Aclear plastic front cover is provided for inspection purposes.

MSP units are supplied in standard height (179mm≅7in.) cases, complying with IEC 297 size 4U.

The rigid case wall is manufactured from a single sheet of hot dipped galvanized steel coatedexternally with Plastisol PVC and internally with a low gloss alkyd paint finish. This constructiontechnique provides improved thermal transfer characteristics over plastic walled cases andcombines exceptional corrosion and flame resilience with good electromagnetic and electrostaticscreening properties allowing many relays to be freely situated in close proximity and hazardousenvironments. When the relay is inserted a leaf spring along the top edge of the module makescontact with a solidly bonded nickel plated steel strip on the interior of the case, providingexcellent earth continuity. This strip is brought out at the rear of the case, above the terminalblock, where it forms a separate earthing terminal. A rigid front mounting flange is providedallowing the entire range of standard cases to be flush mounted without alteration. These flangesare also used to mount the relay inspection cover which is secured by thumbscrews. Securelybonded channels can be provided on the top and bottom surfaces toward the rear of the caseallowing large rigid assemblies to be created by the use of joining strips located in these channels.

This uniform but highly flexible housing system integrates excellent mechanical strength withgood electrical practice in industry standard sizes.

PANEL CUT OUT FLUSHMOUNTING FIXING DETAILS

4 HOLES 4.4mm DIAMETER

99

168 159

52 23.5

10

9745

PUSH BUTTONPROJECTION 10mm

NOT SHOWN TO SCALE

103

177

212

Clearance25 min

157

32

OPTIONAL

OPTIONAL

OPTIONAL

Min28

NOTE Minimum gap between vertical spacing is required in order to

withdraw relay from the case above.

178Required to open case SIZE 100 CASE


01/09/03 Page 21 Issue 2

11.9. Terminal Connection Details.

The rear terminal block accepts both pre-insulated screw and push-on blade type connectors whichmay be used singly or in combination. Each terminal has 1 screw type and 2 blade typeconnectors.

Screw: Each connection uses a 4mm (M4) screw outlet and accepts standardL-shaped ring type connectors designed for 4mm screws.

Blade: Each connection facilitates 2 pre-insulated push-on blades 4.8mmwide 0.8mm thick complying with BS5057.

Combinations: Each terminal will accept either;2 ring type connectors

or 2 push-on blade type connectorsor 1 ring type connector & 1 push-on blade type connector

1

3

5

7

9

11

13

15

17

19

21

23

25

27

2

4

6

8

10

12

14

16

18

20

22

24

26

28

Earth

Rear terminal block connections.

Each terminal

1 screw &2 spade

All information subject to change without noticePublication number Issue 1


01/09/03 Page 22 Issue 2

12. Order Form

Restricted Earth Fault Relay MSP-REF

MSP-REF

Rated Current, 1A 15A 5

Housing, 19" Rack AFlush Mounting D

PBSI Ltd Trading as

P&B ENGINEERINGBell Vue Works,Boundary Street,Manchester.M12 5NG.

Tel: 0161-230-6363Fax: 0161-230-6464

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