PSS®SINCAL 6.5
Protection Coordination
Protection Coordination in Electricity Networks
Published by SIEMENS AG Freyeslebenstraße 1, 91058 Erlangen E D SE PTI SW
SIEMENS PSS SINCAL Protection Coordination Manual
Preface
PSS® is a registered trademark of SIEMENS AG
Copyright SIEMENS AG 2009 All Rights Reserved
Preface
The PSS SINCAL manuals can be divided into three parts:
● the PSS SINCAL System Manual
● technical manuals for electricity and flow networks
● the database description
The user can find the general principles for using the PSS SINCAL manual and the PSS SINCAL
user interface in the PSS SINCAL System Manual.
The technical manuals for electricity networks contain detailed descriptions of the various
calculation methods for electricity networks - such as load flow, or short circuit calculations - and
their input data.
The technical manuals for pipe networks contain detailed descriptions of the various calculation
methods for pipe networks - water, gas and heating - and their input data.
The database description contains a complete description of the data models for electricity and
flow networks.
Copyright
This manual and all the information and illustrations contained in it are copyrighted.
SIEMENS retains all rights, in particular the right to publish, translate, reprint, photocopy, make
microcopies or electronically store in a database.
Previously expressed written permission from SIEMENS is required for any reproduction or use
beyond the limits specified by copyright law.
Warranty
Even though our manuals are thoroughly checked for errors, no liability can be taken for errors
found or any resulting problems or difficulties. Modifications are frequently made to the text and the
software as a part of our routine updates.
SIEMENS PSS SINCAL Protection Coordination Manual
Table of Contents
April 2010
1. Introduction to Protection Coordination 1
2. Protection Simulation 4
2.1 OC Protection Devices 9
2.1.1 Pickup OC Protection Devices 9
2.1.2 Characteristic-Curve Tripping 12
2.1.3 First Instantaneous Tripping 14
2.1.4 Second instantaneous Tripping 14
2.1.5 Third Instantaneous Tripping 15
2.1.6 Measurement Transformer Influence 16
2.1.7 Composition of the Characteristic Curve 17
2.1.8 Determining Intersection for Double Logarithmic Coordinates 18
2.1.9 Determining the State of Protection Devices 19
2.1.10 Graphic Display with Diagrams 20
2.1.11 Graphic Display with Legends 22
2.1.12 Importing and Exporting Protection Device Settings 22
2.2 Types of OC Protection Devices 25
2.2.1 Creating a New OC Protection Device Type 25
2.2.2 Editing OC Protection Device Types 25
2.2.3 Creating and Configuring OC Protection Device Types 28
2.2.4 Copying OC Protection Device Types 29
2.2.5 Configuring OC Protection Device Types 30
2.2.6 Assigning the OC Protection Device Type 43
2.3 Distance-Protection Devices 44
2.3.1 Shapes of Impedance Areas 44
2.3.2 Pickup Distance Protection Devices 47
2.3.3 Tripping with Distance Protection Devices 49
2.3.4 Measurement Transformer Influence 49
2.3.5 Impedance Loops 50
2.3.6 Determining the State of Distance-Protection Device 53
2.3.7 PSS SINCAL Diagrams 53
2.4 Differential Protection Devices 55
PSS SINCAL Protection Coordination Manual SIEMENS
Table of Contents
April 2010
2.4.1 Protection Zone 55
2.5 Teleprotection 56
2.5.1 Signals at OC Protection Devices 57
2.5.2 Signals at Distance Protection Devices 57
2.5.3 Example for Blocked Tripping 58
2.6 Determining Tripping and Waiting Times for Protection Devices 59
2.6.1 Sequence to Determine Times 60
2.6.2 Determining Clearing Times for Faults 61
2.6.3 Distance Protection Tripping due to Phase-Fault Setting 61
2.6.4 Distance Protection Tripping due to Ground-Fault Setting 61
2.6.5 Distance Protection Tripping for Load Current 62
2.7 Recommendations and Warnings 62
3. Protection Routes 63
4. Protection Device Settings 66
4.1 Supported Protection Device Types 67
4.1.1 How Distance Protection Devices Work 69
4.1.2 Circular Tripping Areas 70
4.1.3 Quadrilateral-Shaped Tripping Areas 70
4.1.4 Common 71
4.1.5 7SA500, 7SA501 and 7SA502 72
4.1.6 7SA510, 7SA511 and 7SA513 73
4.1.7 7SA522 74
4.1.8 7SA610, 7SA611, 7SA612, 7SA631 and 7SA632 75
4.1.9 7SL13 76
4.1.10 7SL17, 7SL24, 7SL70 and 7SL73 77
4.1.11 EPAC3100, EPAC3400, EPAC3500, EPAC3600 and EPAC3700 78
4.1.12 LZ91 and LZ92 79
4.1.13 PD531 and PD551 80
4.1.14 PD532 and PD552 81
4.1.15 R1KZ4, R1KZ4A, RK4 and RK4A 82
4.1.16 R1KZ7 and R1KZ7G 83
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April 2010
4.1.17 R1Z25, R1Z25A and R1Z23B 84
4.1.18 R1Z27 85
4.1.19 RD10 86
4.1.20 REL316 87
4.1.21 REL521 and REL561 88
4.1.22 SD124 89
4.1.23 SD135 90
4.1.24 SD135A 91
4.1.25 SD14, SD14A and SD14B 92
4.1.26 SD34A 93
4.1.27 SD35 94
4.1.28 SD35A and SD35C 95
4.1.29 SD36 96
4.2 Calculation Method 97
4.2.1 Entries for Determining Impedance 97
4.2.2 Type of Measurement 103
4.2.3 Selective Grading Factors 109
4.2.4 DISTAL Strategy 110
4.2.5 Line Impedance Strategy 115
4.2.6 Line Impedance Strategy Connected 117
4.2.7 Medium-Voltage Network Strategy 117
4.3 Results of Settings Calculations 120
4.4 Hints and Cautions 121
5. Fault Detection 122
6. Dimensioning 124
6.1 Calculation Methods 125
7. Examples 132
7.1 Example for Protection Coordination 132
7.1.1 Presetting Calculation Settings 133
7.1.2 Creating Protection Devices 133
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7.1.3 Making Fault Observations 136
7.1.4 Making Fault Events 137
7.1.5 Determining Settings for DI Protection Devices 138
7.1.6 Checking Tripping Behavior for Protection Devices 141
7.1.7 Starting the Protection Simulation 141
7.1.8 Displaying and Evaluating the Results 142
7.1.9 Generating Protection-Route Diagrams 144
7.2 Example for Creating Protection Documentation 145
7.2.1 Selecting Grading 146
7.2.2 Creating the Protection Documentation 147
7.2.3 Inserting a Diagram 148
SIEMENS PSS SINCAL Protection Coordination Manual
Introduction to Protection Coordination
April 2010 1
1. Introduction to Protection Coordination
Faults can never be prevented completely in electrical transmission and distribution networks.
PSS SINCAL Protection Coordination, however, has been designed to limit most of the effects of
faults to assure continued operation of the network.
The main goals of PSS SINCAL Protection Coordination are:
● To keep the network operational
When there is a fault, you want to shut down only a minimum amount of equipment to isolate
the fault.
● To prevent the problem from spreading
When there is a fault, a lack of selectivity or overloading can cause the problem to spread.
● To protect the main equipment of the network
Your priority is protecting the most important and most expensive equipment in the network
(generators, transformers, etc.) from the fault.
PSS SINCAL Protection Coordination offers a wide range of procedures covering the complex field
of protecting or examining electrical transmission and distribution networks.
This manual contains the following chapters:
● Protection Simulation
● Protection Routes
● Protection Device Settings
● Fault Detection
● Dimensioning
● Examples
Protection Simulation
PSS SINCAL Protection Simulation calculates the amount of current, voltage, power and
impedance in case of
● One-phase to ground,
● Two-phase to ground,
● Two-phase short circuit and
● Three-phase short circuit
and links these to the setting for the protection device. Calculations are based on VDE or IEC
specifications. Simultaneously, PSS SINCAL accounts for initial load conditions.
Currents from short circuit calculations and the calculated impedances are then used to determine
the pickup protection devices.
Generating Diagrams of Protection Routes
PSS SINCAL can generate protection-route diagrams so that you can check that protection devices
have been set properly.
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Introduction to Protection Coordination
April 2010 2
Determining Settings for Protection Devices
This simulation procedure determines how distance protection devices are set. The various types
of protection-device types in the network and their selective grading factors are used to calculate
the values actually set at the protection device.
Detecting Faults
PSS SINCAL fault detection lets you locate a fault in the supply network. PSS SINCAL calculates
this position from the values registered at the protection device at the moment the fault takes place.
Dimensioning
Low-Voltage Dimensioning calculates minimum one-phase short circuit currents in low voltage
networks. Load flow is determined in the load flow part of the program; minimum one-phase short
circuit current is determined in the short circuit part of the program. The user must keep in mind
that the rated fuse current must be larger than the load current yet smaller than the minimum
permissible one-phase short circuit current in fuse records. PSS SINCAL shows the user any
possible discrepancies in the VDE safeguards.
Protection Coordination Procedure
To process protection coordination or create special data for the protection coordination, the
Calculation Method for Protection Device Coordination must first be switched ON.
The following steps are necessary:
● Create and define the tripping behavior of protection devices
● Define the arc reserve to determine the settings in the network level data
● Create fault observations
Network Calculations
The speed with which network calculations can be made depends primarily on five factors:
● Network size
● Number of regulated elements
● Calculation type
● Available storage capacity
Using Load Flow to Determine Load Voltage
Before protection can be simulated, PSS SINCAL calculates the load flow to determine load
voltage. One reason is that PSS SINCAL needs this load voltage to determine the direction in the
protection simulation.
Determining Permanent Load Currents from Load Flow
Sometimes networks are displayed on a computer in such a way that the load flow problem is not
solvable.
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Introduction to Protection Coordination
April 2010 3
Displaying the Networks for the Calculations
For a detailed description of how the networks are displayed for the calculations, see the chapter
Network Display in the Input Data Manual.
Definitions
Overcurrent Time Protection
PSS SINCAL Overcurrent Time Protection uses current as the criterion of protection, assuring that
the maximum operating current for the equipment is not exceeded for a long period of time. This
protects the network from thermal overloading, from fault currents and from excessive operating
currents.
In this manual, overcurrent time protection devices will also be called OC protection devices.
Distance Protection
PSS SINCAL distance protection determines the distance from the protection device to the fault
location indirectly from the line impedance. The criterion of distance protection is impedance.
PSS SINCAL determines impedance by measuring the current and voltage at the ends of the
equipment to be protected. The amount of impedance is closer to the fault.
Selectivity
PSS SINCAL can detect a fault in the network and shut it off with minimum repercussions to the
network as a whole.
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Protection Simulation
April 2010 4
2. Protection Simulation
PSS SINCAL Protection Simulation can be used to simulate electrical networks with serial and
cross admittance, source voltages for generators, tripping characteristics for protection devices,
and permissible short circuit currents for the equipment. These devices determine the maximum
short circuit currents. PSS SINCAL searches for tripping sequences and times for protection
devices when the network has overcurrents. PSS SINCAL can also simulate, at arbitrary
intersection nodes or in lines, overcurrents caused by short circuits.
PSS SINCAL Short Circuit calculates overcurrents with referred impedance (reference power 1
MVA) and uses symmetrical components to calculate one-phase faults.
General Remarks to Protection Simulation
PSS SINCAL can easily simulate a wide variety of problems in day-to-day network operations. The
range of applications is not limited to the specific problems and needs of network operators.
Like other PSS SINCAL calculation procedures, PSS SINCAL Overcurrent Protection can calculate
the following types of networks in a single operation:
● Utility and industrial networks
● Meshed and/or radial networks
● Medium- and low-voltage networks
● Networks with several voltage levels
● Subnetworks with separate supply
PSS SINCAL Short Circuit calculates short circuit currents. PSS SINCAL Protection Simulation
examines the following kinds of faults:
● One-phase to ground
● Two-phase to ground
● Two-phase short circuit
● Three-phase short circuit
● Currents with and without initial load
● Currents involving line couplings in the zero-phase-sequence
● Currents involving a neutrally connected transformer in the zero-phase-sequence
PSS SINCAL Protection Simulation can:
● Observe various types of protection devices (overcurrent protection, distance protection)
● Define faults anywhere in nodes or lines
● Augment protection-device catalogues to meet individual needs
● Observe more than one time interval to clear the fault
● Consider directional elements with freely definable ranges in its calculations
● Consider fault impedance
● Display tripping curves for protection devices, relative to their smallest node voltage, in a
double logarithmic current-time diagram
● Display more than one subnetwork or network level in a double logarithmic current-time
diagram
● Display the impedance of more than one protection device in more than one subnetwork in the
R-X diagram
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Protection Simulation
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● Use load current to check for tripping errors
● Display tripping characteristics, tripping currents and damage curves in a double logarithmic
current-time diagram
PSS SINCAL Protection Simulation can be used to:
● Determine fault-clearing times at any of the fault locations
● Monitor the selectivity of protection devices
● Check selective gradings for protection devices
● Verify the thermal load of the equipment
● Investigate tripping errors occurring in normal network operation
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Protection Simulation
April 2010 6
Calculation Procedures for Protection Simulation
Illustration: Sequence diagram
Download and check all network data
Calculate load flow
Check, if protection devices get energized under load current
Set protection devices to "not energized" and initialize loop counter to 1
Wait for the command "continue if loop counter is greater than 1"
Generate switches for all open protection devices
Calculate fault currents, voltages and impedances
Are there any more energized protection devices?
Yes
No
Is current at fault observation equal to 0?
Yes No
Fault cannot be disconnected
Fault disconnected
Assign fault currents, voltages and impedances to protection devices
Determine opening times for protection devices
Determine states of protection devices (tripped, energized, inactive)
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Protection Simulation
April 2010 7
Protection Devices
PSS SINCAL Protection Simulation recognizes the following kinds of protection devices:
OC Protection Devices
● Circuit Breakers with Measurement Transformers
● Low-Voltage Circuit Breakers
● Fuses
● Bi-Metallic Circuit Breakers
● Contactors
● Trip Fuses
Distance Protection Devices
● Distance Protection Devices
Differential Protection Devices
● Differential Protection Devices
PSS SINCAL can simulate these protection devices at any of the network elements.
Available Protection Devices in Protection Simulation
In the current version, PSS SINCAL component protection simulation recognizes only the following
types of components:
● All OC protection devices
● Distance protection devices
Checking Load Energizing
Because of the different load conditions, PSS SINCAL increases the current by a safety margin or
reduces the impedance by a safety margin when it checks energizing from the load current. For
network level data, these safety parameters are set in the Protection tab.
OC Protection Devices
PSS SINCAL calculates the load current margin as follows to check the energizing:
0,100
f0,1II Ilfprf
If the resulting test current passes through the protection device’s current-time curve, the load is
energized.
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Protection Simulation
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Distance Protection Devices
PSS SINCAL reduces loop impedances from load voltage and load current as follows:
0,100
f0,1ZZ Z
lfprf
PSS SINCAL uses an angle to create the following test impedance area from impedance and
reduced loop impedance.
Illustration: Test impedance area for load energizing
If the test impedance area superimposes a protection device’s tripping area, the load is energized.
Energizing
The check PSS SINCAL makes depends on the type of the energizing. For current energizing
without tripping, or in directional and non-directional current energizing, PSS SINCAL uses the
admitted load current. For area energizing, PSS SINCAL uses the test impedance area.
X
R
+
Zlf
-
Zprf
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Protection Simulation
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2.1 OC Protection Devices
Each OC protection device has a characteristic curve made up of segments. Segments can be
combined to create tripping characteristics for any type of protection device. Individual segments
are active or inactive, depending on the type of protection device. PSS SINCAL Protection
Simulation recognizes the following type of OC protection device.
● Circuit breakers with measurement transformers
● Low-voltage circuit breakers
● Fuses
● Bi-metallic circuit breakers
● Contactors
● Trip fuses
All protection devices will trip if the current through the protection device crosses the tripping curve
of the protection device. PSS SINCAL recreates the characteristic tripping curve for all OC
protection devices in the same way.
Characteristics
All protection devices have a segmented tripping characteristic curve. Individual segments are
assigned separate tripping characteristics for phase and ground faults as follows:
● Characteristic-curve tripping
● First instantaneous tripping
● Second instantaneous tripping
● Third instantaneous tripping
PSS SINCAL automatically specifies the individual segments of the characteristic curve depending
on the type of protection device. Switches can be used to deactivate individual segments.
If the protection device is connected to the network via measurement transformer, the following can
also influence how the device trips:
● Rated current for the primary measurement transformer
● Rated current for the secondary measurement transformer
● Incoming current at the protection device
Protection devices connected to the network via measurement transformers can also have
directional elements. In this case, the direction set for the current’s angle determines how the
device trips.
For all these options, PSS SINCAL considers directional elements, intermediate transformers,
delays, percentages, etc.
2.1.1 Pickup OC Protection Devices
Modern protection devices can have various kinds of pickup conditions:
● Current pickup
● Underimpedance pickup
● Undervoltage pickup
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Protection Simulation
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● Impedance pickup – area pickup
Each of these conditions also has an end time. If the device has not tripped before this time, then it
trips automatically.
For a detailed description of the pickup input data, see the section on Pickup in the chapter on
Protection Coordination in the Input Data Manual.
Current Pickup
This condition is fulfilled when values drop below a minimum current. Simply going below this
current fulfills the condition.
PSS SINCAL supports three different types of current pickup:
● Directional current pickup (without tripping).
This type of pickup considers the setting for the direction (forwards, backwards). There is no
final time, so the protection device does not necessarily trip.
● Directional current pickup.
This type of pickup considers the setting for the direction (forwards, backwards).
● Non-directional current pickup
Underimpedance Pickup
Several conditions have to be fulfilled before there is underimpedance pickup.
● Exceeding the limits of minimum current I> and
● Being below the voltages V> until V>> at a current of between I> and I>>
● Exceeding the current I>>
Illustration: Current and voltage in underimpedance pickup
I
V
Inactive
Energized
V>
V>>
I> I>>
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Undervoltage Pickup
Falling below a minimum voltage and a minimum current fulfills the condition for this type of pickup.
Illustration: Current and voltage in undervoltage pickup
Impedance Pickup – Area Pickup
With impedance pickup, the impedance registered by the protection device must be within a
prescribed impedance area to meet the pickup condition. A SIEMENS area describes this type of
pickup.
The pickup area can be assigned two different final times (directional and non-directional).
I
V
Inactive
Energized
V>
I>
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Protection Simulation
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2.1.2 Characteristic-Curve Tripping
The tripping characteristics are defined by a curve with double logarithmic current-time axes.
Depending on the type of protection device, current and time values are shown as:
● Absolute values (fuses)
● Standard values (bi-metallic circuit breakers, circuit breakers with transformers, etc.)
Absolute values for tripping characteristics cannot be modified. When the operator enters a
differently rated current, PSS SINCAL automatically selects other tripping characteristics.
Illustration: Tripping characteristics for fuses with different rated currents
Multiplying the settings for current or time changes the standard values for a characteristic curve,
moving the characteristic curve either horizontally or vertically in the current-time diagram. When
the operator enters different tripping characteristics, PSS SINCAL automatically selects a different
standard characteristic curve.
PSS SINCAL can display currents for standard characteristic curves:
● In amperes
● Relative to the rated current
The current for the tripping is then:
● Current = norm x setting
● Current = norm x setting x rated current
t
I
IN1 IN2
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PSS SINCAL always displays the time value for the tripping as:
● Norm x setting
Illustration: Standard characteristic curve for a protection device
Illustration: Standard characteristic curve with different settings for current
Illustration: Standard characteristic curve with different settings for time
t
I
I=I1 I=I2
t
I
I=I1 I=I2
t
I
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Protection Simulation
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2.1.3 First Instantaneous Tripping
Current and time values define the first instantaneous tripping.
PSS SINCAL can display currents for the first instantaneous tripping:
● In amperes
● Relative to the rated current
● Relative to the setting for characteristic-curve tripping
The current for the tripping is then:
● Current = setting
● Current = setting x rated current
● Current = setting x current for the characteristic-curve tripping
PSS SINCAL assigns a fixed tripping time for the first short circuit.
Illustration: Characteristic curve for first instantaneous tripping
2.1.4 Second instantaneous Tripping
Current and time values define the second instantaneous tripping.
PSS SINCAL can display currents for the second instantaneous tripping:
● In amperes
● Relative to the rated current
● Relative to the setting for characteristic-curve tripping
● Relative to the setting for the first instantaneous tripping
The current for the tripping is then:
● Current = setting
● Current = setting x rated current
● Current = setting x current for the characteristic-curve tripping
● Current = setting x current for the first instantaneous tripping
PSS SINCAL assigns a fixed tripping time for the second short circuit.
t
I
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Illustration: Characteristic curve for the second instantaneous tripping
2.1.5 Third Instantaneous Tripping
Current and time values define the third instantaneous tripping.
PSS SINCAL can display currents for the third instantaneous tripping:
● In amperes
● Relative to the rated current
● Relative to the setting for characteristic-curve tripping
● Relative to the setting for the first instantaneous tripping
● Relative to the setting for the second instantaneous tripping
The current for the tripping is then:
● Current = setting
● Current = setting x rated current
● Current = setting x current for the characteristic-curve tripping
● Current = setting x current for the first instantaneous tripping
● Current = setting x current for the second instantaneous tripping
PSS SINCAL assigns a fixed tripping time for the third short circuit.
Illustration: Characteristic curve for third instantaneous tripping
I
t
t
I
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Protection Simulation
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2.1.6 Measurement Transformer Influence
The current through the protection device is influenced by the transmission ratio between the
measurement transformers:
● Primary and secondary rated current
If the current entering the protection device is not the same as the measurement transformer’s
secondary rated current, PSS SINCAL also has to consider the ratio between:
● The secondary rated current and the incoming current
Directional Element Settings
If there is a directional element, the preliminary settings for direction and range angle influence the
behavior of a protection device.
PSS SINCAL has the following settings for direction:
● Non-directional (current can have any angle)
● Forward (angle range towards the line)
● Reverse (angle range away from the line)
The settings for direction do not really depend on whether the current flows towards the line or
away from it. They only set the range of angles used. The current’s angle always refers to a
voltage. This can be either:
● Current voltage (voltage remaining after the short circuit)
● Voltage from the load flow (voltage stored at the protection device)
If the current voltage is zero (protection devices located directly at the fault location), PSS SINCAL
uses the voltage from the load flow.
Directional Elements, Intermediate Measurement Transformers, Delays and
Percentages
PSS SINCAL uses multipliers to consider these ratings for:
● Measurement transformers
● Characteristic-curve tripping
● First instantaneous tripping
● Second instantaneous tripping
● Third instantaneous tripping
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2.1.7 Composition of the Characteristic Curve
Characteristic curves are made up of segments. PSS SINCAL considers only those segments that
are switched on.
Illustration: Segments of characteristic curve, first, second and third instantaneous tripping
Illustration: Characteristic curve with active curve and second instantaneous tripping
I
t
I
t
I
t
I
t
I
t
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Illustration: Characteristic curve with active curve, first or third instantaneous tripping
Illustration: Characteristic curve with active first and second instantaneous tripping
2.1.8 Determining Intersection for Double Logarithmic Coordinates
Linear interpolation in a double logarithmic system of coordinates produces the wrong results.
Linear interpolation assumes a linear system of coordinates.
Illustration: Double logarithmic system
Double logarithmic systems must therefore be converted to double linear systems for linear
interpolation. This is done using a base-ten logarithm. To prevent calculation errors, the results can
be multiplied by a constant factor.
Ilog
tlog
0,1
1
10
1 10 100
I
t
I
t
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)l(10logFIloglin
)t(10logFtloglin
Illustration: Double linear system
In this double linear system, linear interpolation can be made to find the point of intersection. The
results of the linear interpolation are then converted back to the double logarithmic system.
F
t
log
l in
10t
Direct linear interpolation in a double logarithmic system would produce an error of up to 10%.
2.1.9 Determining the State of Protection Devices
A protection device can have the following states:
● Inactive
● Picked-up
● Tripped
Inactive
A protection device is inactive if the current passing through it is less than the smallest current of
its tripping characteristics or less than the smallest current of all the instantaneous tripping. The
current passing through the protection device does not cross the tripping characteristic curve.
Picked-Up
A protection device has been picked up if the current passing through it is equal to, or greater than,
the smallest current of its tripping characteristics or is equal to, or greater than, the current of all the
instantaneous tripping. The tripping time is where the current passing through the protection device
intersects with the tripping characteristic curve. This means that all picked-up protection devices
can be assigned tripping times.
-1
0
1
0 1 2 Ilin
tlin
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Tripped Condition
In every simulation loop, PSS SINCAL trips the protection device that has the smallest tripping
time.
To allow for calculation errors, a safety time interval is added to the smallest tripping time.
Within this interval, all the protection devices trip. If the smallest tripping time is 150 ms and the
safety time interval is 0.5 ms, all the protection devices with tripping times less than 150.5 ms trip.
2.1.10 Graphic Display with Diagrams
PSS SINCAL provides two diagrams to display the results on the screen:
● Double logarithmic current-time diagram
● Linear R-X diagram
PSS SINCAL provides various diagram types so that settings and evaluations are easier for the
user to handle.
OC protection devices need an impedance area to be displayed as an R-X diagram. PSS SINCAL
normally uses a circle to represent this area. PSS SINCAL uses the calculated currents and
voltages at the protection device and determines the phase where the tripping current is flowing.
To determine the radius for the circle, the minimum impedance can be calculated from:
● The phase-ground loop
● Both phase-loops
Advantages of a Double Logarithmic Current-Time Diagram
● This proves the characteristic curves are unique.
● It is simple to compare these diagrams with the stair-shaped characteristic curves of distance-
protection devices.
● It shows the destruction limit.
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Illustration: Double logarithmic current-time diagram
Advantages of an R-X Diagram
● This is a simple way to compare the areas.
● The impedance to the fault location can be shown as a cursor.
● It enables a comparison with protection devices for distance protection.
Illustration: R-X diagram
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2.1.11 Graphic Display with Legends
This function lets you create your own legends for ranges and input data for individual OC
protection devices. Simply switch Insert Legend… ON in the protection device’s pop-up menu.
Illustration: Dialog box for Protection Device Legend
Use Select function to insert new legends or update existing ones.
You can insert up to two legends per protection device. They can be defined with the options for
Range and Input Data in the Insert Legend section.
Update existing Legends assigns all existing legends the settings you have entered in Options.
Use Options to define the legend’s layout (to either the right or the left of the protection device) as
well as the distances from the protection device to the legends (for range and input data).
When Use only selected protection devices is switched ON, PSS SINCAL uses all selected
settings in the dialog box only for previously selected protection devices. If this is not switched ON,
PSS SINCAL considers all the protection devices in the current view.
2.1.12 Importing and Exporting Protection Device Settings
PSS SINCAL can import or export OC protection device settings.
Importing Protection Device Settings
This function imports OC protection device settings from a DIGSI XML file. DIGSI has an
import/export interface that lets you use the DIGSI XML file to exchange protection device settings.
This file can read in protection device settings from DIGSI for use in PSS SINCAL.
Click Import Settings… in the pop-up menu of the protection device to activate this function.
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Illustration: Import Protection Device Settings
This opens the Import Protection Device Settings dialog box. In this dialog box the DIGSI XML
file can be selected for import.
The Import Options section specifies the group of settings from DIGSI you want to import:
● First setting:
The first setting group from the DIGSI XML file is used automatically.
● Setting group name:
This option is used to enter the name for the setting group you want to import.
When Use setting address for identification is switched ON, PSS SINCAL attempts to use the
address of the setting to assign the settings for this type of protection device. When this option is
switched OFF, PSS SINCAL uses the name of the setting to assign them.
Exporting Protection Device Settings
This function exports OC protection device settings to a DIGSI XML file. DIGSI has an
import/export interface that lets you use the DIGSI XML to exchange protection device settings.
This file can transfer protection device settings from PSS SINCAL to DIGSI.
Click Export Settings… in the pop-up menu of the protection device to switch this function ON.
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Illustration: Export Protection Device Settings
This opens the Export Protection Device Settings dialog box. In this dialog box the DIGSI XML
file can be defined for export. If you have selected more than one protection devices, you need to
select a directory for export.
In the Export Options section you can select between two modes.
● Create reduced file:
Only PSS SINCAL protection device settings are exported.
● Update existing file:
If a DIGSI XML file exists, PSS SINCAL protection device settings can be updated without
changing the other settings in the file.
If multiple protection devices are selected, this list of options is not available. In this case,
PSS SINCAL creates a new DIGSI XML file with the name of the protection device for each
protection device you have selected.
Finally, you can define the DIGSI setting group for export:
● First setting:
PSS SINCAL automatically uses the first setting group from the selected DIGSI XML file. This
option is only available when you update the DIGSI file.
● None:
No group of settings is created. PSS SINCAL only writes a value in the DIGSI XML file. This
option is only available when you create a new file.
● Setting group name:
This option is used to enter the name for the setting group you want to export.
When the option Use setting address for identification is switched ON, PSS SINCAL exports the
setting address to the DIGSI XML file as an attribute for assigning settings. When this option is
switched OFF, PSS SINCAL uses the name of the settings as an attribute for the assignment.
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2.2 Types of OC Protection Devices
PSS SINCAL uses segmented tripping characteristics to simulate the functions of OC protection
devices. The scope and the functions of these individual segments are stored in a special database
for protection device types.
This lets you recreate different OC protection device types in PSS SINCAL without any problems.
PSS SINCAL has a database for OC protection device types with approximately 2500 types. If you
cannot find the OC protection device type you need in this global database, it can also be created
and configured in a local database.
OC protection device types are divided into the following types:
● Circuit breakers with measurement transformers
● Low-voltage circuit breakers
● Fuses
● Bi-metallic circuit breakers
● Contactors
● Trip fuses
2.2.1 Creating a New OC Protection Device Type
File – Administration – New Protection Database... in the menu creates an empty protection
database that is not assigned to any network for the present (see the section on New Protection
Database in the chapter on Basic Functions). In the Options dialog box you can assign the
database.
2.2.2 Editing OC Protection Device Types
Insert – Standard Type – Overcurrent Time Protection… opens the screen form for working on
OC protection device types, if you have switched ON the calculation method for protection
coordination.
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Illustration: Menu for opening the screen form for an OC protection device type
Illustration: Screen form for editing OC protection device types
The screen form for editing OC protection device types has two sections:
● Browser for type selection
● Data screen area
The browser for type selection has the type selected for editing. PSS SINCAL displays all
settings for this type in the data screen area, where they can be modified.
Note: The data for global types cannot be modified since this information is a standard part of
PSS SINCAL and is maintained by Siemens. But data for local types can be modified, new types
can be added and existing types can be deleted. The copy function simplifies adding new types.
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Toolbar
Use the toolbar to switch important functions of the browser ON to process the types.
Create new OC protection device type
Copy selected OC protection device type
Insert copied OC protection device type
Delete selected OC protection device type
Define filter
Clicking Create new OC protection device type creates a new OC protection device type. Note
that new OC protection device types can only be created in the local protection device type
database.
Clicking Copy selected OC protection device type prepares the OC protection device type you
have selected in the browser on the clipboard so it can be inserted in the local protection device
type database.
OC protection device types copied to the clipboard with the Copy function can be inserted with
Insert copied OC protection device type to the current position in the browser (but only in the
local protection device type database).
Clicking Delete selected OC protection device type deletes the OC protection device type
selected in the browser. Only local protection device types can be deleted.
Click Define filter to define filters for limiting protection device types.
Pop-Up Menu
Click the right mouse button on an OC protection device type in the browser to display the pop-up
menu.
Illustration: Pop-up menu in the OC protection device type browser
This pop-up menu lets you edit the OC protection device type directly. The functions Expand and
Collapse open or close the tree.
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2.2.3 Creating and Configuring OC Protection Device Types
To create a new OC protection device type, first select the form for new type in the browser of the
local database. Then select New in the pop-up menu.
Illustration: Pop-up menu for creating a new OC protection device type
Then configure the new OC protection device type in the data screen area.
Illustration: Screen form for configuring a OC protection device type
To edit an existing OC protection device type, simply select this in the browser and change its
configuration accordingly in the data screen area.
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2.2.4 Copying OC Protection Device Types
When OC protection device types are very similar, it is easier just to copy them. Select the type you
want to copy in the screen form and open the pop-up menu.
Illustration: Pop-up menu for copying an OC protection device type
Select Copy in the menu and insert the OC protection device type in the local database. You need
to select the corresponding form (in this case a circuit breaker) in the browser of the local database
and open the pop-up menu.
Illustration: Pop-up menu for inserting an OC protection device type
Select Paste to copy the OC protection device type to the local database.
Before you can configure the new OC protection device type, you need to select it in the browser of
the local database.
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2.2.5 Configuring OC Protection Device Types
OC protection device types are configured in different screen forms according to the functionality of
the OC protection device.
Configuring General Data
You need to select the collective entry in the browser of the local database to configure the general
data.
Illustration: Screen form for configuring general data for a OC protection device type
This defines the Name of the OC protection device type. PSS SINCAL displays this later within the
legend for the network diagram. The Manufacturer and User Name are supplementary
information, and as such are not needed later.
Angle Determining sets the method used to determine the impedance angle for the direction
decision.
Rated Current (Phase) and Rated Current (Ground) are just supplementary information.
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Configuring a Tripping Type
Basic Data
This defines the behavior of the OC protection device for the particular segment.
Illustration: Screen form for configuring the basic data of a tripping type
Normally tripping types are made up of the type of OC protection device and the protection
behavior. The following abbreviations for individual protection behavior according to IEC 255-3 can
be found in the global protection database:
Abbrev. Protection behavior
DEF Definite-time characteristic
NOR Normal inverse characteristics
VER Very inverse characteristics
EXT Extremely inverse characteristics
LTE Long time inverse characteristics
OVO Overload characteristics
OVM Overload memory characteristics
O%% Overload characteristics with pre-load in %, where %% = 29, 40, 60, 80, 99 (= 100%)
RES Residual characteristics
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The following abbreviations for the individual protection behavior according to ANSI /IEEE can be
found in the global protection database:
Abbrev. Protection behavior
INV Inverse (AMZ inv) characteristics
SIV Short inverse (AMZ inv) characteristics
LIV Long inverse (AMZ inv) characteristics
MIV Massive inverse (AMZ inv) characteristics
VIV Strong inverse (AMZ inv) characteristics
EIV Extremely inverse (AMZ inv) characteristics
DIV Equal inverse (AMZ inv) characteristics
I2T Quadratic inverse (AMZ inv) characteristics
The following abbreviations for bi-metallic devices and circuit breakers can be found in the global
protection database:
Abbrev. Protection behavior
K or C Cold characteristics
W Warm characteristics
The following names for protection devices, whose settings depend on the secondary current
transformer, can be found in the global protection database:
Abbrev. Protection behavior
…_1 1 A current transformer (e.g.. 7SJ63_1.NOR)
…_5 5 A current transformer (e.g.. 7SJ63_5.NOR)
The following names analogous to the version number in the product catalog (e.g. 3WN1.4,
3WN6.D) for the low voltage circuit breaker 3WN can be found in the global protection database.
The following names for fuses can be found in the global protection database:
Abbrev. Protection behavior
VDE_100 100 A low voltage fuses according to VDE (I-t characteristics with average operating time behavior)
VDEu_... Low voltage fuses according to VDE (I-t characteristics with the fastest operating time behavior)
VDEo_... Low voltage fuses according to VDE (I-t characteristics with the slowest operating time behavior)
VDE-H_500 500 A high voltage fuses according to VDE
3N.._... Siemens low voltage fuses
3G.._… Siemens high voltage fuses
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Ip Section for the Segment for Characteristic-Curve Tripping
Phase Tripping and Ground Tripping determine whether the tripping type has a segment with
current/time characteristic-curve tripping for phase currents or ground currents. The following
values are available:
● None:
No characteristic-curve tripping
● In:
Characteristic-curve tripping with current related to rated transformer current
● A:
Characteristic-curve tripping with current in amperes
Phase I2t Limiting and Ground I
2t Limiting determine whether characteristic-curve tripping has
an I2t current limit. The following values are available:
● None:
No I2t current limit
● In:
I2t current limit with current related to rated transformer current
● A:
I2t current limit with current in amperes
I> Section for Segment with First Instantaneous Tripping
Phase Tripping and Ground Tripping determine whether the current tripping type has a first
instantaneous tripping for phase currents or ground currents. The following values are available:
● None:
No first instantaneous tripping
● In:
First instantaneous tripping with current related to rated transformer current
● A:
First instantaneous tripping with current in amperes
● Ip:
First instantaneous tripping with current related to the current for characteristic-curve tripping
Phase I2t Limiting and Ground I
2t Limiting determine whether the first instantaneous tripping has
an I2t current limit. The following values are available:
● None:
No I2t current limit
● In:
I2t current limit with current related to rated transformer current
● A:
I2t current limit with current in amperes
● Ip:
I2t current limit with current related to the current for characteristic-curve tripping
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I>> Section for Segment with Second Instantaneous Tripping
Phase Tripping and Ground Tripping determine whether the current tripping type has a second
instantaneous tripping for phase currents or ground currents. The following values are available:
● None:
No second instantaneous tripping
● In:
Second instantaneous tripping with current related to rated transformer current
● A:
Second instantaneous tripping with current in amperes
● Ip:
Second instantaneous tripping with current related to the current of the characteristic-curve
tripping
● I>:
Second instantaneous tripping with current related to the current for first instantaneous tripping
Phase I2t Limiting and Ground I
2t Limiting determine whether the second instantaneous tripping
has an I2t current limit. The following values are available:
● None:
No I2t current limit
● In:
I2t current limit with current related to rated transformer current
● A:
I2t current limit with current in amperes
● Ip:
I2t current limit with current related to the current for characteristic-curve tripping
● I>:
I2t current limit with current related to the current for first instantaneous tripping
I>>> Section for Segment with Third Instantaneous Tripping
Phase Tripping and Ground Tripping determine whether the current tripping type has a third
instantaneous tripping for phase currents or ground currents. The following values are available:
● None:
No third instantaneous tripping
● In:
Third instantaneous tripping with current related to rated transformer current
● A:
Third instantaneous tripping with current in amperes
● Ip:
Third instantaneous tripping with current related to the current for characteristic-curve tripping
● I>:
Third instantaneous tripping with current related to the current for first instantaneous tripping
● I>>:
Third instantaneous tripping with current related to the current for second instantaneous
tripping
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Phase I2t Limiting and Ground I
2t Limiting determine whether the third instantaneous tripping
has an I2t current limit. The following values are available:
● None:
No I2t current limit
● In:
I2t current limit with current related to rated transformer current
● A:
I2t current limit with current in amperes
● Ip:
I2t current limit with current related to the current for characteristic-curve tripping
● I>:
I2t current limit with current related to the current for first instantaneous tripping
● I>>:
I2t current limit with current related to the current for second instantaneous tripping
Section for Tripping Characteristics
If there is characteristic-curve tripping, the appropriate tripping characteristics need to be entered.
Enter characteristic-curve values as described in the chapter on Screen Form for Characteristics
Input.
Illustration: Dialog box for editing current/time tripping characteristics
For the tripping characteristics, select I/t Curve in the Function field.
For the Type, you normally enter IT1 or IT2. If the type contains a 1, PSS SINCAL uses these
characteristics to determine the intersecting point that has the pickup current. If the type contains a
2, PSS SINCAL displays these characteristics in the current/time diagrams of Diagram View.
Characteristic-curve tripping requires at the very least a characteristic curve for tripping with an
entry for type containing a 1.
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The additional name in the basic data for the characteristic curve is usually the same as the
protection behavior. There is, however, no explicit entry for this additional name.
Illustration: Fuse with an entry for two tripping characteristics
OC protection device types with K (Cold) and W (Warm) tripping have an unusual feature when
this abbreviation has also been entered in the basic data of the characteristics as an additional
name. In this case, PSS SINCAL displays both characteristic curves in the current/time diagrams of
Diagram View.
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Illustration: Bimetal with cold and warm tripping characteristics
Tripping Function
If characteristic curve tripping exists, enter the appropriate function for calculating tripping
characteristics. Enter the parameters for the respective function as described in the chapter on
Screen Form for Characteristics Input.
Illustration: Dialog box for editing the function for calculating tripping characteristics
For the tripping characteristics, select a value for a function, e.g. Function 1, in the Function field.
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Only one entry for tripping characteristics is allowed. Normally the protection behavior can be
entered under Type and Name. PSS SINCAL does not, however, have specific entries for types or
names.
Illustration: Circuit breaker (CT) with transformer and normal inverse tripping
Since the tripping characteristics calculated with this function are reference characteristics, you
have to select In (= current entry for rated transformer current) in the Ip column.
Illustration: Protection device type with Function 1 with settings
You need to enter the appropriate settings for the function you have selected.
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To calculate tripping characteristics, this function proceeds from the initial value I/Ip to the end value
I/Ip. The result is a factor ft, which, multiplied by the time setting value for the characteristics tripping
Tp, produces the tripping time t.
tpfTt
PSS SINCAL needs to have the tripping time in seconds. If you want to have the time at the
protection device in minutes, enter a factor of 60.0 in the function to convert from minutes to
seconds.
Function 1
3PI
I
1Pf
2P
p
t
Type Parameter
1 Parameter P1
2 Parameter P2
3 Parameter P3
20 Initial value I/Ip
21 End value I/Ip
Function 2
8P
6P
p
5P2P
p
t
7PI
I
4P
3P
I
I
ln1Pf
Type Parameter
1 Parameter P1 (60.0 to convert to seconds)
2 Parameter P2
3 Parameter P3 (initial load)
4 Parameter P4
5 Parameter P5
6 Parameter P6
7 Parameter P7
8 Parameter P8
20 Initial value I/Ip
21 End value I/Ip
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Settings
This defines the value ranges for entries for current and time of OC protection devices for the
particular protection function.
Illustration: Screen form for configuring value ranges
Enter value ranges for the OC protection device type as described in the chapter on Screen Form
for Characteristics Input.
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Illustration: Screen form for configuring a value range
This data screen form describes a setting at the OC protection device.
Name is the abbreviation for the setting in the protection device description. The Unit of the setting
is also found in the protection device description. Status is used to document a setting or switch
this ON for input in the OC protection device screen form.
Setting Address contains the setting at the protection device.
Type defines the connection between setting according to description and how it is used in
PSS SINCAL. PSS SINCAL has the following values for the configuration:
Type Function
SWp Characteristic-curve tripping phase switchable
SW> First instantaneous tripping phase switchable
SW>> Second instantaneous tripping phase switchable
SW>>> Third instantaneous tripping phase switchable
SWep Characteristic-curve tripping ground switchable
SWe> First instantaneous tripping ground switchable
SWe>> Second instantaneous tripping ground switchable
SWe>>> Third instantaneous tripping ground switchable
Ip Current characteristic-curve tripping phase
I> Current first instantaneous tripping phase
I>> Current second instantaneous tripping phase
I>>> Current third instantaneous tripping phase
Iep Current characteristic-curve tripping ground
Ie> Current first instantaneous tripping ground
Ie>> Current second instantaneous tripping ground
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Ie>>> Current third instantaneous tripping ground
F_Ip Factor for current characteristic-curve tripping phase
F_I> Factor for current first instantaneous tripping phase
F_I>> Factor for current second instantaneous tripping phase
F_I>>> Factor for current third instantaneous tripping phase
F_Iep Factor for current characteristic-curve tripping ground
F_Ie> Factor for current first instantaneous tripping ground
F_Ie>> Factor for current second instantaneous tripping ground
F_Ie>>> Factor for current third instantaneous tripping ground
Tp Time characteristic-curve-tripping phase
T> Time first instantaneous tripping phase
T>> Time second instantaneous tripping phase
T>>> Time third instantaneous tripping phase
Tep Time characteristic-curve-tripping ground
Te> Time first instantaneous tripping ground
Te>> Time second instantaneous tripping ground
Te>>> Time third instantaneous tripping ground
F_Tp Factor for time characteristic-curve tripping phase
F_T> Factor for time first instantaneous tripping phase
F_T>> Factor for time second instantaneous tripping phase
F_T>>> Factor for time third instantaneous tripping phase
F_Tep Factor for time characteristic-curve tripping ground
F_Te> Factor for time first instantaneous tripping ground
F_Te>> Factor for time second instantaneous tripping ground
F_Te>>> Factor for time third instantaneous tripping ground
I2Ip Current I2t limit characteristic-curve tripping phase
I2I> Current I2t limit first instantaneous tripping phase
I2I>> Current I2t limit second instantaneous tripping phase
I2I>>> Current I2t limit third instantaneous tripping phase
I2Iep Current I2t limit characteristic-curve tripping ground
I2Ie> Current I2t limit first instantaneous tripping ground
I2Ie>> Current I2t limit second instantaneous tripping ground
I2Ie>>> Current I2t limit third instantaneous tripping ground
I2TIp Time I2t limit characteristic-curve tripping phase
I2T> Time I2t limit first instantaneous tripping phase
I2T>> Time I2t limit second instantaneous tripping phase
I2T>>> Time I2t limit third instantaneous tripping phase
I2Tep Time I2t limit characteristic-curve tripping ground
I2Te> Time I2t limit first instantaneous tripping ground
I2Te>> Time I2t limit second instantaneous tripping ground
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I2Te>>> Time I2t limit third instantaneous tripping ground
All additional types are only for documentation and do not influence how the OC protection device
type is configured.
2.2.6 Assigning the OC Protection Device Type
Once a new OC protection device has been created, PSS SINCAL displays a screen form where
you can assign the OC protection device type. Before you can do this, you have to select Settings
in the browser for the OC protection device. Select the filter button to preselect the OC protection
device types.
Illustration: Dialog box for preselecting the OC protection device types
PSS SINCAL displays the OC protection device types you have selected as a list.
Illustration: Preselected OC protection device types
When you select a type, PSS SINCAL assigns this to the OC protection device for phase and
ground tripping. If you want to use another type for ground tripping, assign this at ground. You can
only select between the individual tripping types of OC protection devices.
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Illustration: Screen form for selecting the OC protection device type for ground tripping
2.3 Distance-Protection Devices
Impedance areas describe distance protection devices. Distance-protection devices trip when the
impedance registered at the protection device is within a given impedance area.
PSS SINCAL recognizes various kinds of impedance areas, from simple conductance circles to
freely definable impedance areas, so that all distance protection devices in use can be simulated.
2.3.1 Shapes of Impedance Areas
PSS SINCAL represents real protection devices with the following types of tripping areas:
● Basic areas:
Rectangular or circle
● SIEMENS
● Freely definable
Depending on the shape of the area, PSS SINCAL stipulates the following:
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Basic Areas
This is the simplest shape. To define a rectangular area, enter the following:
● Active resistance
● Reactive reactance
● Quadrant input:
I (first quadrant)
A (all quadrants)
Depending on the type of protection device, this area can be either a rectangle or a circle.
Illustration: Rectangular impedance area
SIEMENS Areas
These areas have the typical SIEMENS shape for distance-protection devices. To define a
SIEMENS area, enter the following:
● X+A (reactive reactance)
● X-A (reactive reactance)
● RA1 (active resistance)
● RA2 (active resistance)
● (angle)
R
X
R, X
R
X
R, X
-R, -X
Type: I Type: A
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SIEMENS areas always have the following shape:
Illustration: SIEMENS impedance area
Freely Definable Areas
Here the user can simulate any kind of area. Ten straight lines and four circles define an area. The
straight lines, the circles and the input sequence can be defined freely.
The straight lines pass through a point that has been defined and are at an angle to the positive R
axis. Straight lines are defined by the following:
● R (active resistance)
● X (reactive reactance)
● (angle)
Three points define circles: starting, arc and end points. Circles always begin at a starting point, go
through the arc and end points and then back to the starting point. The procedure is important
since it creates the limiting line.
Circles can be lengthened or shortened in R and X directions or rotated at an angle to the positive
R axis.
Circles are defined by
● RA (active resistance at the starting point)
● XA (reactive reactance at the starting point)
● RB (active resistance at the arc point)
● XB (reactive reactance at the arc point)
● RE (active resistance at the end point)
● XE (reactive reactance at the end point)
● FR (factor for distortion in direction R)
● FX (factor for distortion in direction X)
● (angle for rotation)
R
X
X+A
X-A
RA1
RA2
-RA1
-RA2
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Illustration: Example of a freely defined impedance area limited by two straight lines and a circle
If there are problems setting the limiting line, either:
● Change the beginning and end point
● Change the element sequence
2.3.2 Pickup Distance Protection Devices
Modern protection devices can have various kinds of pickup conditions:
● Current pickup
● Underimpedance pickup
● Undervoltage pickup
● Impedance pickup – area pickup
Each of these conditions also has an end time. If the device has not tripped before this time, then it
trips automatically.
For a detailed description of the pickup input data, see the section on Pickup in the chapter on
Protection Coordination in the Input Data Manual.
Current Pickup
This condition is fulfilled when values drop below a minimum current. Simply going below this
current fulfills the condition.
PSS SINCAL supports three different types of current pickup:
● Directional current pickup (without tripping):
This type of pickup considers the setting for the direction (forwards, backwards). There is no
final time, so the protection device does not necessarily trip.
● Directional current pickup:
This type of pickup considers the setting for the direction (forwards, backwards).
● Non-directional current pickup
R
X
K1
G2
G1
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Underimpedance Pickup
Several conditions have to be fulfilled before there is underimpedance pickup.
● Exceeding the limits of minimum current I> and
● Being below the voltages V> until V>> at a current of between I> and I>>
● Exceeding the current I>>
Illustration: Current and voltage in underimpedance pickup
Undervoltage Pickup
Falling below a minimum voltage and a minimum current fulfills the condition for this type of pickup.
Illustration: Current and voltage in undervoltage pickup
Impedance Pickup – Area Pickup
With impedance pickup, the impedance registered by the protection device must be within a
prescribed impedance area to meet the pickup condition. A SIEMENS area describes this type of
pickup.
I
V
Inactive
Energized
V>
I>
I
V
Inactive
Energized
V>
V>>
I> I>>
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The pickup area can be assigned two different final times (directional and non-directional).
2.3.3 Tripping with Distance Protection Devices
In all kinds of tripping, the registered impedance of the protection device must be within a
prescribed impedance area.
Individual protection devices are assigned all kinds of areas with times for tripping.
To determine tripping behavior, PSS SINCAL sorts all areas of a protection device according to
tripping times (registered impedance within the area).
Illustration: Constructing areas for a protection device
All areas are sorted by times (in ascending order), independent of their shape. This assures that
the area that can trip fastest is always checked first and can trip.
2.3.4 Measurement Transformer Influence
Current and voltage transformers supply individual distance-protection devices with data.
All protection devices measure impedance either on:
● The primary side
● The secondary side
Measurement – Primary Side
Currents and voltages are not converted.
Measurement – Secondary Side
All currents are assigned this transmission ratio:
● Rated current primary/rated current secondary times
● Factor for intermediate-current transformers
R
X
t1
t2
t
R
X
R
X
t3
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All voltages are assigned this transmission ratio:
● Rated voltage primary/rated voltage secondary times
● Factor for intermediate-voltage transformers
Considering Directional Elements
The angle of the impedance registered for directional elements needs to be checked before
checking whether the registered impedance is inside an area.
Depending on the direction, the angle must be within its own angle range.
PSS SINCAL accepts the following settings for the direction:
● Non-directional (angle range the same)
● Forward (angle range towards the line)
● Reverse (angle range back from the line)
The setting for the direction determines in which angle range the impedance must be picked up.
The impedance angle always refers to a voltage. This voltage comprises the following parts:
… Current voltage (remaining voltage from short circuit)
… Voltage from load flow (voltage stored at the protection device)
… Voltage outside the fault (all phase voltage not affecting by the fault) rotated 90 °
A percentage can be set for all the parts. The voltage determining the angle, however, is always
the sum of all parts evaluated and comes, for example, from
fLa V%0V%0V%100
or
fLa V%20V%20V%100
The sum of the percentages does not have to be 100%!
2.3.5 Impedance Loops
The way the following impedance loops are treated differs for rectangular, SIEMENS or freely
defined impedance areas.
● Phase 1 – ground
● Phase 2 – ground
● Phase 3 – ground
● Phase 1 – phase 2
● Phase 2 – phase 3
● Phase 3 – phase 1
aV
LV
fV
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In rectangular impedance-areas, all impedances for all impedance loops are checked.
In SIEMENS or freely defined impedance areas, all impedance loops to be checked must be
defined. PSS SINCAL only considers impedances from active impedance loops.
Determining Impedance
The impedances of phase-phase loops have the reference
)II(jX)II(RVV21L21L21
)II(jX)II(RVV32L32L32
)II(jX)II(RVV13L13L13
After these have been converted, PSS SINCAL shows the active resistances (R12, R23, R31) and
reactive reactances (X 12, X 23, X31) for the protection device.
221
221
2121212112
)IIIm()IIRe(
)VVIm()IIIm()VVRe()IIRe(R
221
221
2121212112
)IIIm()IIRe(
)VVRe()IIIm()VVIm()IIRe(X
232
232
3232323223
)IIIm()IIRe(
)VVIm()IIIm()VVRe()IIRe(R
232
232
3232323223
)IIIm()IIRe(
)VVRe()IIIm()VVIm()IIRe(X
213
213
1313131331
)IIIm()IIRe(
)VVIm()IIIm()VVRe()IIRe(R
213
213
1313131331
)IIIm()IIRe(
)VVRe()IIIm()VVIm()IIRe(X
The impedances of phase-ground loops have the references
L
eL
L
eLeLL11
X
XjX
R
RRI)jXR(IV
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L
eL
L
eLeLL22
X
XjX
R
RRI)jXR(IV
L
eL
L
eLeLL33
X
XjX
R
RRI)jXR(IV
After they have been converted, PSS SINCAL shows the active resistances (R1e, R2e, R3e) and
reactive reactances (X 1e, X 2e, X3e) for the protection device.
L
ee1
L
ee1
L
ee1
L
ee1
1
L
ee11
L
ee1
e1
X
XIIIm
R
RIIIm
X
XIIRe
R
RIIRe
)VIm(X
XIIIm)VRe(
X
XIIRe
R
L
ee1
L
ee1
L
ee1
L
ee1
1
L
ee11
L
ee1
e1
X
XIIIm
R
RIIIm
X
XIIRe
R
RIIRe
)VRe(R
RIIIm)VIm(
R
RIIRe
X
L
ee2
L
ee2
L
ee2
L
ee2
2
L
ee22
L
ee2
e2
X
XIIIm
R
RIIIm
X
XIIRe
R
RIIRe
)VIm(X
XIIIm)VRe(
X
XIIRe
R
L
ee2
L
ee2
L
ee2
L
ee2
2
L
ee22
L
ee2
e2
X
XIIIm
R
RIIIm
X
XIIRe
R
RIIRe
)VRe(R
RIIIm)VIm(
R
RIIRe
X
L
ee3
L
ee3
L
ee3
L
ee3
3
L
ee33
L
ee3
e3
X
XIIIm
R
RIIIm
X
XIIRe
R
RIIRe
)VIm(X
XIIIm)VRe(
X
XIIRe
R
L
ee3
L
ee3
L
ee3
L
ee3
3
L
ee33
L
ee3
e3
X
XIIIm
R
RIIIm
X
XIIRe
R
RIIRe
)VRe(R
RIIIm)VIm(
R
RIIRe
X
The following references must be set at the protection device.
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L
e
L
e
X
Xand
R
R
2.3.6 Determining the State of Distance-Protection Device
Distance-protection devices can have the following states:
● Inactive
● Picked-up
● Tripped
Because of the signal locks, protection devices that have already been tripped must be considered
in the future clearing procedure.
Inactive
A distance-protection device is inactive if none of the pickup conditions are fulfilled.
When no pickup conditions have been set, the impedance registered by the distance-protection
device must be outside all impedance areas for the protection device to be inactive.
Picked-up
A distance-protection device has been picked up if one of the pickup conditions is fulfilled.
When no pickup conditions have been set, the registered impedance of the distance-protection
device must be inside at least one impedance area for the protection device to be picked up.
Tripped
In every simulation loop, the protection device with the smallest tripping time (either a distance
protection device or OC device) is considered tripped.
To allow for calculation errors, a safety time interval is added to the smallest tripping time.
All protection devices within this interval trip. If the smallest tripping time is 150 ms and the safety
time interval is 0.5 ms, all the protection devices with tripping times less than 150.5 ms trip.
2.3.7 PSS SINCAL Diagrams
PSS SINCAL has two types of diagram to display the results on the screen:
● Double logarithmic current-time diagram
● Linear R-X diagram
PSS SINCAL provides various diagram types so that settings and evaluations are easier for the
user to handle.
Current-time coordinates must be calculated from the impedance areas to a protection device to be
displayed in the double logarithmic current-time diagram.
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A loop passing through all impedance areas, and sorted according to tripping times, determines
these coordinates as follows:
● PSS SINCAL determines the impedance at the intersection of the straight lines and the limit of
the impedance area
SpZimpedance
● The present current and the impedance registered are the impedance current
Sp
trip
tripSpZ
ZII
● The tripping time for the current impedance is the same as the time tSp when the current ISp also
trips. A pair of coordinates for the double logarithmic current-time diagram has been calculated
completely.
These current-time coordinates in the double logarithmic current-time diagram are stair-shaped.
Advantages of an R-X Diagram
● This is a simple way to compare the areas.
● The impedance up to the fault location is displayed as an arrow.
● They can be compared with OC protection devices.
Illustration: R-X diagram
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Advantages of a Double Logarithmic Current-Time Diagram
● This is a simple way to compare these with the characteristic curves of distance-protection
devices.
● It shows the destruction limit.
Illustration: Double logarithmic current-time diagram
2.4 Differential Protection Devices
In the current PSS SINCAL version, differential protection devices are used only to limit protection
zones in reliability calculations.
Special Shape for Entering Differential Protection Devices
Entering a differential protection group lets you use OC and distance protection devices to limit the
protection zone.
2.4.1 Protection Zone
To limit a protection zone, the topology of the protection device and the differential protection group
are necessary. Depending on the entry, PSS SINCAL has the following protection zones:
Differential Protection for Nodes or Busbars
All differential protection devices in a differential protection group must have the same insert node.
In PSS SINCAL, however, not all the node or busbar connections need a protection device. Only
one device is necessary to define the differential protection zone.
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Differential Protection for Elements
All differential protection devices in a differential protection group must be placed at the same
network element.
Differential Protection for Fields
Differential protection devices in a differential protection group must comprise an entire network
area. These devices are placed at different elements in different nodes.
2.5 Teleprotection
In the real world, signal lines connect OC and distance-protection devices. Signals from other
protection devices therefore can keep individual protection devices from pickup.
There is no limit to the number of ways protection devices can block each other.
● OC protection device – OC protection device
● OC protection device – distance-protection device
● Distance-protection device – OC protection device
● Distance-protection device – distance-protection device
There is no limit to the number of signals, either. The following types of signals can be used to
block protection devices.
● Activated: signal picked up
● Deactivated: signal inactive
Pickup is blocked when one or more signals prevent pickup. To define a signal for blocking, the
following must be entered:
Protection Device Receiving the Signal (Protection Device 1)
● Key – protection device 1
● Zone name for condition
● Tripping for zone to be locked (phase or ground)
Protection Device Sending the Signal (Protection Device 2)
● Key – protection device 2
● Zone name
● Tripping for condition (phase or ground)
● Type of signal
Note: This only prevents the respective unit or area from being picked up.
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2.5.1 Signals at OC Protection Devices
A signal (picked-up or inactive) is sent to each OC protection device for the phase and ground
setting at each tripping unit. If signals are blocked, PSS SINCAL treats a tripping unit at an
overcurrent protection device like a zone for a distance protection device. PSS SINCAL has the
following tripping units:
● Characteristic-curve tripping
● First short circuit current tripping
● Second short circuit current tripping
● Third short circuit current tripping
Note: With OC protection devices, all tripping units always produce a signal as follows:
● Current tripping units (phase and ground) send the signal PICKED-UP.
● Units with smaller tripping time (reserve protection for phase and ground) also send the signal
PICKED-UP.
● Units with higher tripping time or inactive units send the signal INACTIVE.
OC protection devices with PICKED-UP characteristic-curve tripping and second short circuit
current tripping send the following signals in second short circuit current tripping as an active
tripping unit:
● Characteristic-curve tripping: PICKED-UP
● First short circuit current tripping: INACTIVE
● Second short circuit current tripping: PICKED-UP
● Third short circuit current tripping: INACTIVE
Note: OC protection devices tripping in one time step do not have any current in the following time
steps. All tripping units of tripped OC protection devices therefore must always send the signal
INACTIVE in the following time steps.
2.5.2 Signals at Distance Protection Devices
Each distance-protection device has a signal (picked-up/inactive) for phase and ground setting in
each tripping area. PSS SINCAL has the following kinds of levels:
● FIRST LEVEL
● SECOND LEVEL
● THIRD LEVEL
● Pickup (impedance pickup – pickup area)
● SIEMENS areas:
Identified by the area name
● Freely definable areas:
Identified by the area name
The tripping area and the impedance the protection device registers determine which tripping area
produces which signals. PICKED-UP protection devices react to the following criteria:
● Impedance registered within the tripping area – valid direction:
PICKED-UP
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● Impedance registered within the tripping area – invalid direction:
INACTIVE
● Impedance registered outside the tripping area:
INACTIVE
All tripping areas for inactive protection devices send the signal INACTIVE.
Note: Distance-protection devices tripping in one time step do not have any current in the following
time steps and consequently do not register impedance. All tripping units of tripped distance-
protection devices therefore always send the signal INACTIVE in the following time steps:
2.5.3 Example for Blocked Tripping
Signals should ideally be blocked to trip faults in the first line to be protected. For reasons of
simplification, this example shows a purely Ohmic line with a resistance of three Ohms.
Illustration: Line with protection devices
Individual impedance areas register at different distances into the line. In this example, the
following is true for both protection devices:
Ohm2R1
Ohm05.3RB1
Ohm4R2
The fault occurs at a distance of 2.5 Ohm. The signal for the stipulated tripping level R1B, t1B is
always the tripping level R1, t1 of the protection device located opposite.
Illustration: Range of tripping areas
t
K1
R2, t2
K2
R2, t2
R1, t1 R1, t1 R1B, t1B R1B, t1B
SG2 SG1
SG1 SG2
K1 SG1
R=3 Ohm
SG2 K2
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Illustration: Signal behavior
Illustration: Protection devices with tripping times
In our example, the protection device’s switching time must be greater than:
1B1ttt
2.6 Determining Tripping and Waiting Times for Protection Devices
Calculations for the tripping time of a protection device do not depend on the type of protection
device. The following times are considered in the calculations:
Waiting Time
time from when the fault was encountered until the protection device was picked-up
Imaginary Waiting Time
waiting time calculated due to peculiarities in the algorithm to calculate the tripping time and waiting
time for a protection device
Present Tripping Time
protection device tripping time determined from existing currents and voltages
Previous Fault-Clearing Time
clearing time for final calculations
K1 K2
Clearing time of the fault: t1B
t1B t1
SG1 SG2
t
K1 K2
R1, t1 R1B, t1B
SG2 SG1
Signal of SG2 and
level R1, t1 = ENERGIZED
SG1 SG2
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Present Fault-Clearing Time
clearing time for present calculations
2.6.1 Sequence to Determine Times
The time is determined as follows:
Tripping Conditions for Phase Faults
● Values – phase 1
● Values – phase 2
● Values – phase 3
Tripping Conditions for Ground Faults
● Values – phase 1
● Values – phase 2
● Values – phase 3
The tripping times are calculated as follows:
● The tripping time is calculated from setting ranges and phases
● If the tripping range changes for OC protection devices (characteristic-curve tripping, first short
circuit current tripping)
set the previous status of the protection device to inactive
● If the previous status is inactive
set the waiting time the same as the previous clearing time
● If the previous status is picked-up
and the tripping time is less than previous clearing time
– there is immediate tripping for an electronic protection device
– there is delayed tripping for a conventional protection device
● Calculate the present tripping time
add up the waiting time, present tripping time and imaginary waiting time
● Compare this with the clearing time for all previous setting ranges and phases
use the smallest time for each protection device
This algorithm can, however, create a problem with immediate or a delayed tripping.
The present clearing time can be smaller than the previous clearing time. Since, however, this is
impossible, the protection device must be given an imaginary waiting time.
Immediate Tripping
The imaginary waiting time for the protection device is the previous clearing time minus the present
tripping time.
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Delayed Tripping
The imaginary waiting time must consider the effects of heat from the new current on the protection
device. Differentiation must be made between the following two cases:
● Tripping time for the current from 1000.0 to 0.3 seconds
The 0.3 seconds must be effectively run out before the protection device trips.
● Tripping time for the current from 0.7 to 0.3 seconds
The tripping time for the current is between 0.3 and 0.7 seconds.
As can be seen in both cases, the algorithm for delayed tripping must consider both the previous
time and the previous current.
2.6.2 Determining Clearing Times for Faults
PSS SINCAL calculates clearing times for faults as follows:
● PSS SINCAL makes these clearing times equal to the smallest tripping time of all other
protection devices in the present simulation loop.
PSS SINCAL stops protection calculations automatically if:
● There are no more picked-up protection devices
● Current at the fault location is equal to zero
2.6.3 Distance Protection Tripping due to Phase-Fault Setting
For phase-fault tripping, all currents in all phases are used to fulfill the tripping conditions. The
currents in the three phases do not need to be the same size.
To fulfill the phase-tripping conditions, the current for each phase is observed separately.
The tripping conditions for the phase faults are always checked separately from the actual faults in
the network.
2.6.4 Distance Protection Tripping due to Ground-Fault Setting
Ground tripping occurs only when a ground current that does not equal zero is produced right at
the protection device. The ground current is determined from
321eIIII
The current through the protection device is different in all three phases. To fulfill the ground-
tripping conditions, the current for each phase is observed separately.
Ground-fault currents can also cause tripping due to phase-fault settings, so the characteristics for
either the phase or ground can pickup the protection device.
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PSS SINCAL uses the minimum value from the following to determine pickup behavior:
● Current/voltage Phase 1 and settings ground faults
● Current/voltage Phase 2 and settings ground faults
● Current/voltage Phase 3 and settings ground faults
● Current/voltage Phase 1 – Phase 2 and settings phase faults
● Current/voltage Phase 2 – Phase 3 and settings phase faults
● Current/voltage Phase 3 – Phase 1 and settings phase faults
2.6.5 Distance Protection Tripping for Load Current
Load current flowing through the protection device may not pickup the protection device for phase-
fault tripping.
The load flow calculations only determine the current and the voltage for Phase 1. The currents
and voltages in Phases current related to Two and Three are produced by rotating 120 or -120
degrees.
2.7 Recommendations and Warnings
The operator needs to consider the following when determining currents, times and tripping states:
● Protection devices always switch off all three phases simultaneously.
● One- or three-phase short circuit current is always determined as maximum short circuit
current. If the short circuit does not occur during crossover (null), there is less present current
and the tripping time is larger. If the damage curve of the network element crosses the tripping
curve, it can lead to heat damage and even change the tripping sequence.
● If the tripping time is greater than the previous fault-clearing time, the tripping time can be reset
so the protection devices that are already picked up do not reach maximum head load and shut
down. Otherwise, this could damage network elements and even change the tripping
sequence.
● When the safety-time interval entered is larger than the switching time, this gap produces
another current distribution for the time between the network’s switching time and safety-time
interval. This condition can alter the tripping sequence.
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3. Protection Routes
PSS SINCAL generates various diagrams for the network and the built-in protection devices. These
diagrams are used to check the accuracy of the protection setting.
If you only create specific routes in the network as a diagram, you need to have a Network Element
Group of the type "protection route" for these elements.
Note: PSS SINCAL only generates diagrams for protection devices if these have been switched
ON in the selective grading diagram (see the section on Locating Protection Devices in the chapter
on Data Description in the Input Data Manual).
PSS SINCAL has the following diagrams:
● Tripping Behavior
● Ratio Impedances (Z)
● Ratio Reactances (X)
● Impedance and Tripping Areas
Tripping Behavior
This diagram shows the tripping behavior of protection devices over time, depending on the
impedance registered.
PSS SINCAL generates one diagram per protection route for each protection device. This diagram
also contains protection devices located in the protection route being displayed so that selective
tripping can be set and tripping times can be easily checked.
Illustration: Diagram Protection Routes – Tripping Behavior
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Ratio Impedances (Z)
This diagram shows the impedance registered by the protection device compared to the amount of
impedance in the protection route. The tripping levels of the protection device are shown as
horizontal lines in the diagram.
PSS SINCAL generates one diagram per protection route for each protection device.
Illustration: Diagram Protection Routes – Ratio Impedances
Ratio Reactances (X)
This diagram shows the reactance registered by the protection device compared to the amount of
reactance in the protection route. The tripping levels of the protection device are shown as
horizontal lines in the diagram.
PSS SINCAL generates one diagram per protection route for each protection device.
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Illustration: Diagram Protection Routes – Ratio Reactances
Impedance and Tripping Areas
This diagram shows the impedance areas of the protection device. Impedance registered by the
protection device (at the particular node) can also help you visualize the protection route.
PSS SINCAL generates one diagram per protection route for each protection device.
Illustration: Diagram Protection Routes – Impedance and Tripping Areas
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4. Protection Device Settings
This simulation procedure determines the settings for distance protection devices. PSS SINCAL
calculates the values actually set at the protection device from the types of protection devices in
the network and their selective distance factors.
In addition to settings, this simulation procedure also generates diagrams as selective tripping
schedules. Larger high- and medium-voltage networks are updated all the time. This means that a
lot of effort is required to maintain the tripping plans. Formerly, second and third selective tripping
levels in meshed networks had to be calculated by hand. This meant a great deal of work and
yielded calculations that were at best approximate. Now, however, PSS SINCAL can calculate
these levels quickly and accurately.
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Basic Calculation Sequence for Protection Device Settings
Illustration: Sequence diagram
4.1 Supported Protection Device Types
Modern distance-protection devices are like computers that trip and turn off if there is a fault, using
internal programs that measure current and voltage values and their settings.
Protection devices are so complex that they need to be simulated to understand them properly.
A special module has been integrated into PSS SINCAL protection coordination that can simulate
many kinds of distance-protection devices. Additional protection devices can easily be added to the
module.
Download and check all network data
Depending on strategy, reconstruct the network to determine settings
Loop – protection device
Set minimum impedance for limits with the help of short circuits
Have all protection devices been calculated?
No
Short circuit in new network – calculate wandering short circuit in parallel lines
Loop – steps
Calculate settings and tripping area from measurement type, type of protection device and minimum impedance
Set intersections for protection device tripping area with network resistance curve (range of protection device)
Have all steps been calculated?
Prepare results
Yes
No
Set points for limits of bends
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PSS SINCAL supports the following types of protection devices:
Type Function group Manufacturer
Common Common
7SA500 7SA SIEMENS
7SA501 7SA SIEMENS
7SA502 7SA SIEMENS
7SA510 7SA SIEMENS
7SA511 7SA SIEMENS
7SA513 7SA SIEMENS
7SA522 7SA SIEMENS
7SA610 7SA SIEMENS
7SA611 7SA SIEMENS
7SA612 7SA SIEMENS
7SA631 7SA SIEMENS
7SA632 7SA SIEMENS
7SL13 7SL SIEMENS
7SL17 7SL SIEMENS
7SL24 7SL SIEMENS
7SL70 7SL SIEMENS
7SL73 7SL SIEMENS
EPAC3100 PD5 ALSTOM
EPAC3400 PD5 ALSTOM
EPAC3500 PD5 ALSTOM
EPAC3600 PD5 ALSTOM
EPAC3700 PD5 ALSTOM
LZ91 LZ9
LZ92 LZ9
PD531 PD5 ALSTOM
PD532 PD5 ALSTOM
PD551 PD5 ALSTOM
PD552 PD5 ALSTOM
R1KZ4 R1KZ SIEMENS
R1KZ4A R1KZ SIEMENS
R1KZ7 R1KZ7 SIEMENS
R1KZ7G R1KZ7 SIEMENS
R1Z23B R1Z25 SIEMENS
R1Z25 R1Z25 SIEMENS
R1Z25A R1Z25 SIEMENS
R1Z27 R1Z27 SIEMENS
RD10 SD1
REL316 PD5 ABB
REL521 PD5 ABB
REL561 PD5 ABB
RK4 R1KZ SIEMENS
RK4A R1KZ SIEMENS
SD124 SD1 AEG
SD135 SD3 AEG
SD135A SD3 AEG
SD14 SD1 AEG
SD14A SD1 AEG
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SD14B SD1 AEG
SD34A SD34 AEG
SD35 SD3 AEG
SD35A SD3 AEG
SD35C SD3 AEG
SD36 SD36 AEG
Some 50 protection device types are divided up into 10 groups, depending on how they work.
Except for minor differences, PSS SINCAL simulates a particular group’s protection devices in the
same way.
4.1.1 How Distance Protection Devices Work
All distance protection devices work in the same way. They determine the impedances of all the
impedance loops (conductor – conductor and conductor – ground) from current and voltage in the
three-phase network.
Then PSS SINCAL checks whether the registered loop impedance is inside one or more prescribed
impedance areas. Each impedance area is assigned a constant tripping time. The constant time
per step produces jumps in the tripping time (steps) if the loop impedances registered are in
different areas.
The settings at the protection device are used as parameters for the impedance area according to
the current network. Depending on the type of protection device, impedance areas are based on
circles or impedance quadrilaterals.
All settings are secondary values at the protection device. The primary values are calculated from
the factor of the current transformer,
sec
pricurr i
Iü ,
from the factor of the voltage transformer
sec
privolt V
Vü
and from the settings.
All PSS SINCAL predefined protection device types are described below with the relevant
parameters for PSS SINCAL. Protection device types in a group have the same parameters as
used in PSS SINCAL.
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4.1.2 Circular Tripping Areas
To define a circle with the center at the origin of the coordinates, simply enter the radius. Additional
entries can be made to move the center of the circle along the positive resistance axis. Depending
on where the center is, the circle is known as:
● An Impedance Circle:
The center is located in the origin of the coordinate.
● A Modified Impedance Circle:
The center is located between origin of the coordinates and positive radius. The circle passes
through the reactance axis of the impedance area.
● A Conductance Circle:
The center of the circle is located right at the positive radius. Thus, the reactance axis is simply
a tangent of the circle.
This type of protection device is technically known as an analogous protection device. Protection
devices are complicated mechanical measurement devices.
4.1.3 Quadrilateral-Shaped Tripping Areas
The simplest form of the impedance quadrilateral is a rectangle. To define these, simply enter a
value for resistance and reactance in the first quadrants. PSS SINCAL then constructs an area
symmetrical to the resistance and reactance axes. Entering an angle changes the rectangle to a
diamond.
Unlike circles, the two different shapes have no special names:
● Rectangular impedance quadrilateral
● Diamond-shaped impedance quadrilateral
Technically, these protection devices are known as digital protection devices and resemble modern
PCs.
Since digital protection devices have become much cheaper to buy and maintain than analogous
protection devices, digital devices are replacing analogous ones. To protect the network when
devices are exchanged, the new devices must be assigned the same tripping area as the old
devices. Newer digital protection devices can also simulate circular tripping areas (digital
analogous protection).
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Protection Device Settings
April 2010 71
4.1.4 Common
How these devices work:
● Digital protection device with settings R, X, Z and angle phi
Measurement types supported:
● Impedance Circle
● Modified Impedance Circle
● Conductance Circle
● Impedance Quadrilateral
● Reactance Quadrilateral
● MHO Circle
● MHO Circle Polarized
Rated currents supported:
● PSS SINCAL does not check for a specific rated current.
Zone R [Ohm] X [Ohm] Z [Ohm] Angle phi [°]
1 0.001 to 9999.000 (step of 0.001)
0.001 to 9999.000 (step of 0.001)
0.001 to 9999.000 (step of 0.001)
30 to 90 (step of 1)
2 - " - - " - - " - Such as phi1
3 - " - - " - - " - - " -
IP - " - - " - - " - - " -
PP - " - - " - - " - - " -
Procedural Simulation
The primary value for R, X and Z is calculated from
curr
voltsecpri ü
üRR
or
curr
voltsecpri ü
üXX
or
curr
voltsecpri ü
üZZ
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Protection Device Settings
April 2010 72
4.1.5 7SA500, 7SA501 and 7SA502
How these devices work:
● Digital protection devices with settings R and X
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
Zone R [Ohm] X [Ohm]
1 0.05 to 65.32 (step of 0.01) 0.05 to 65.32 (step of 0.01)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a rectangular impedance quadrilateral.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
The primary value for R and X is calculated from
intcurr
voltsecpri üü
üRR
or
intcurr
voltsecpri üü
üXX
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Protection Device Settings
April 2010 73
4.1.6 7SA510, 7SA511 and 7SA513
How these devices work:
● Digital protection devices with settings R and X
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
Zone R [Ohm] X [Ohm]
1 0.05 to 130.00 (step of 0.01) 0.05 to 65.00 (step of 0.01)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a rectangular impedance quadrilateral.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
The primary value for R and X is calculated from
intcurr
voltsecpri üü
üRR
or
intcurr
voltsecpri üü
üXX
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Protection Device Settings
April 2010 74
4.1.7 7SA522
How these devices work:
● Digital protection device with settings R, X, Z and angle phi
Measurement types supported:
● Impedance Quadrilateral
● MHO Circle
● MHO Circle Polarized
Rated currents supported:
● 1 ampere
● 5 ampere
Zone R [Ohm] X [Ohm] Z [Ohm] Angle phi [°]
1 0.005 to 250.000 (step of 0.001)
0.005 to 250.000 (step of 0.001)
0.005 to 200.000 (step of 0.001)
30 to 90 (step of 1)
2 - " - - " - - " - such as phi1
3 - " - - " - - " - - " -
IP - " - - " - - " - - " -
PP - " - - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a diamond-shaped impedance quadrilateral.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
The primary value for R, X and Z is calculated from
intcurr
voltsecpri üü
üRR
or
intcurr
voltsecpri üü
üXX
or
intcurr
voltsecpri üü
üZZ
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Protection Device Settings
April 2010 75
4.1.8 7SA610, 7SA611, 7SA612, 7SA631 and 7SA632
How these devices work:
● Digital protection devices with settings R, X and angle phi
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] X [Ohm] Angle phi [°]
1 0.05 to 250.00 (step of 0.01) 0.05 to 250.00 (step of 0.01) 30 to 90 (step of 1)
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
5 ampere rated current
Zone R [Ohm] X [Ohm] Angle phi [°]
1 0.01 to 50.00 (step of 0.01) 0.01 to 50.00 (step of 0.01) 30 to 90 (step of 1)
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
The tripping area is a diamond-shaped impedance quadrilateral.
Procedural Simulation
The primary value for R and X is calculated from
curr
voltsecpri ü
üRR
or
curr
voltsecpri ü
üXX
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Protection Device Settings
April 2010 76
4.1.9 7SL13
How these devices work:
● Digital protection device with settings X and RX
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
Zone X [Ohm] R/X [1] Angle phi [°]
1 Resistance chain: 0.02, 0.04, 0.08, 0.15, 0.30, 0.50, 1.00, 2.00, 4.00, 8.00, 16.00 and 32.00
2,00 88
2 Resistance chain: 0.02, 0.04, 0.08, 0.15, 0.30, 0.50, 1.00, 2.00, 2.00, 5.00, 10.00, 10.00 and 10.00
- " - Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a diamond-shaped impedance quadrilateral with sides that are always inclined
by 2 degrees.
Procedural Simulation
Note that resistors must have the X value on the secondary side.
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
Resistance chains of the individual zones have a serial connection with a base resistance of
0.1 ohm. PSS SINCAL automatically adds the base resistance to the indicated settings. When
these settings are passed on in protection device configuration, you need to be very careful that the
values are not reduced a second time by the base resistance. The primary value for R and X is
calculated from
intcurr
voltsec1pri1 üü
ü
X/R
)0,2tan(0,1)X1,0(X
intcurr
voltsec2sec1pri2 üü
ü
X/R
)0,2tan(0,1)XX1,0(X
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Protection Device Settings
April 2010 77
intcurr
voltsec3sec2sec1pri3 üü
ü
X/R
)0,2tan(0,1)XXX1,0(X
or
X/RXRpri1pri1
X/RXRpri2pri2
X/RXRpri3pri3
4.1.10 7SL17, 7SL24, 7SL70 and 7SL73
How these devices work:
● Digital protection devices with settings X and R
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
Zone X [Ohm] R/X [1] Angle phi [°]
1 Resistance chain: 0.02, 0.04, 0.08, 0.15, 0.30, 0.50, 1.00, 2.00, 4.00, 8.00, 16.00 and 32.00
1.00 to 4,00 (step of 1) 88
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a diamond-shaped impedance quadrilateral with sides that are always inclined
by 2 degrees.
Procedural Simulation
Note that resistors must have the X value on the secondary side.
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
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Protection Device Settings
April 2010 78
Resistance chains of the individual zones have a serial connection with a base resistance of
0.1 ohm. PSS SINCAL automatically adds the base resistance to the indicated settings. When
these settings are passed on in protection device configuration, you need to be very careful that the
values are not reduced a second time by the base resistance. The primary value for R and X is
calculated from
intcurr
voltsecpri üü
ü
X/R
)0,2tan(0,1)X1,0(X
or
X/RXRpripri
4.1.11 EPAC3100, EPAC3400, EPAC3500, EPAC3600 and EPAC3700
How these devices work:
● Digital protection devices with settings R and X
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] X [Ohm]
1 0.01 to 200.00 (step of 0.01) 0.01 to 200.00 (step of 0.01)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
5 ampere rated current
Zone R [Ohm] X [Ohm]
1 0.02 to 40.00 (step of 0.01) 0.02 to 40.00 (step of 0.01)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
The tripping area is a rectangular impedance quadrilateral.
Procedural Simulation
The primary value for R and X is calculated from
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Protection Device Settings
April 2010 79
curr
voltsecpri ü
üRR
or
curr
voltsecpri ü
üXX
4.1.12 LZ91 and LZ92
How these devices work:
● Digital protection devices with settings M, N and R/X
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
Zone M [1] N [1] R/X [1] Angle phi [°]
1 0.1, 0.5 or 5.0 1.0 to 99.0 (step of 1.0) 1.0 to 5.0 (step of 1.0) 85
2 0.1, 1.0 or 10.0 - " - - " - Such as phi1
3 - " - - " - - " - - " -
IP - " - - " - - " - - " -
PP - " - - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a diamond-shaped impedance quadrilateral with sides that are always inclined
by 5 degrees.
Procedural Simulation
Note that resistors must have the X value on the secondary side.
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
The primary value for R and X is calculated from
intcurr
voltpri üüX/RN
ü))0,5tan(0,1(100MX
or
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Protection Device Settings
April 2010 80
X/RXRpripri
4.1.13 PD531 and PD551
How these devices work:
● Digital protection devices with settings R and X
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] X [Ohm]
1 0.10 to 10.00 (step of 0.01) and 10.0 to 200.0 (step of 0.1)
0.10 to 10.00 (step of 0.01) and 10.0 to 200.0 (step of 0.1)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
5 ampere rated current
Zone R [Ohm] X [Ohm]
1 0.02 to 10.00 (step of 0.002) and 10.0 to 40.0 (step of 0.02)
0.02 to 10.00 (step of 0.002) and 10.0 to 40.0 (step of 0.02)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
The tripping area is a rectangular impedance quadrilateral.
Procedural Simulation
The primary value for R and X is calculated from
curr
voltsecpri ü
üRR
or
curr
voltsecpri ü
üXX
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Protection Device Settings
April 2010 81
4.1.14 PD532 and PD552
How these devices work:
● Digital protection devices with settings R, X, Z and angle phi
Measurement types supported:
● Impedance Quadrilateral
● Impedance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] X [Ohm] Z [Ohm] Angle phi [°]
1 0.10 to 200.00 (step of 0.01)
0.10 to 200.00 (step of 0.01)
0.05 to 200.00 (step of 0.01)
40.0 to 90.00 (step of 1.0)
2 - " - - " - - " - Such as phi1
3 - " - - " - - " - - " -
IP - " - - " - - " - - " -
PP - " - - " - - " - - " -
5 ampere rated current
Zone R [Ohm] X [Ohm] Z [Ohm] Angle phi [°]
1 0.02 to 40.00 (step of 0.01)
0.02 to 40.00 (step of 0.01)
0.01 to 40.00 (step of 0.01)
40.0 to 90.00 (step of 1.0)
2 - " - - " - - " - Such as phi1
3 - " - - " - - " - - " -
IP - " - - " - - " - - " -
PP - " - - " - - " - - " -
The tripping area is a diamond-shaped impedance quadrilateral (settings R, X and angle phi) or an
impedance circle (set at Z).
Procedural Simulation
The primary value for R, X and Z is calculated from
curr
voltsecpri ü
üRR
or
curr
voltsecpri ü
üXX
or
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Protection Device Settings
April 2010 82
curr
voltsecpri ü
üZZ
4.1.15 R1KZ4, R1KZ4A, RK4 and RK4A
How these devices work:
● Analogous protection devices with the setting R and the measurement range c
Measurement types supported:
● Impedance Circle
● Modified Impedance Circle
● Conductance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
Zone R [Ohm] c [1]
1 Resistance chain: 0.1, 0.2, 0.4, 0.8, 1.6 and 3.2 0.1, 0.2, 0.5, 1.0, 2.0, 5.0 or 10.0
2 Resistance chain: 0.2, 0.4, 0.8, 1.6 and 3.2 Such as c1
3 Resistance chain: 0.4, 0.8, 1.6 and 3.2 - " -
IP Resistance chain: 0.1, 0.2, 0.4, 0.8, 1.6, 3.2, 10.0, 20.0 and 962.7 - " -
PP - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is an impedance circle, a modified impedance circle or a conductance circle.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,5
Iü n
int
Resistance chains of the individual zones have a serial connection with a base resistance of
1 ohm. PSS SINCAL automatically adds the base resistance to the indicated settings. When these
settings are passed on in protection device configuration, you need to be very careful that the
values are not reduced a second time by the base resistance. Set the diameter of the circle of the
respective measurement type. The primary value for R is calculated from
intcur
voltsecpri üü
ü)1R1(c1R
or
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Protection Device Settings
April 2010 83
intcurr
voltsecsecpri üü
ü)2R1R1(c2R
or
intcurr
voltsecsecsecpri üü
ü)3R2R1R1(c3R
4.1.16 R1KZ7 and R1KZ7G
How these devices work:
● Analogous protection devices with the setting R, the measurement range c and the angle phi
Measurement types supported:
● Impedance Circle
● Modified Impedance Circle
● Conductance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
Zone R [Ohm] c [1] Angle phi [°]
1 Resistance chain: 0.1, 0.2, 0.3, 0.3, 1.0, 2.0, 3.0 and 3.0
0.1, 0.2, 0.5, 1.0 or 2.0 0.0, 20.0, 30.0, 40.0, 50.0 or 55.0
2 Resistance chain: 0.2, 0.4, 0.4, 1.0, 2.0, 3.0 and 3.0
Such as c1 Such as phi1
3 - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is an impedance circle, a modified impedance circle or a conductance circle.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,5
Iü n
int
Resistance chains of the individual zones have a serial connection with a base resistance of
1 ohm. PSS SINCAL automatically adds the base resistance to the indicated settings. When these
settings are passed on in protection device configuration, you need to be very careful that the
values are not reduced a second time by the base resistance. Set the diameter of the circle of the
respective measurement type. The primary value for R is calculated from
PSS SINCAL Protection Coordination Manual SIEMENS
Protection Device Settings
April 2010 84
intcurr
voltsecpri üü
ü)1R1(c1R
or
intcurr
voltsecsecpri üü
ü)2R1R1(c2R
or
intcurr
voltsecsecsecpri üü
ü)3R2R1R1(c3R
4.1.17 R1Z25, R1Z25A and R1Z23B
How these devices work:
● Analogous protection devices with the setting R, the measurement range c, the correction
factor C3 and the angle phi
Measurement types supported:
● Impedance Circle
● Modified Impedance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
Zone R [Ohm] c [1] Angle phi [°]
1 Resistance chain: 0.1, 0.2, 0.4, 0.8, 1.6 and 3.2
0.1, 0.2, 0.5, 1.0, 2.0, 5.0 or 10.0 60.0, 64.0, 68.0, 71.0, 74.0, 76.0, 78.0 or 80.0
2 Resistance chain: 0.4, 0.8, 1.6 and 3.2
Such as c1 Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is either an impedance circle or a modified impedance circle.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
3C
Iü n
int
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Protection Device Settings
April 2010 85
Resistance chains of the individual zones have a serial connection with a base resistance of
1 ohm. PSS SINCAL automatically adds the base resistance to the indicated settings. When these
settings are passed on in protection device configuration, you need to be very careful that the
values are not reduced a second time by the base resistance. Set the diameter of the circle of the
respective measurement type. The primary value for R is calculated from
intcurr
voltsecpri üü
ü)1R1(c1R
or
intcurr
voltsecsecpri üü
ü)2R1R1(c2R
or
intcurr
voltsecsecsecpri üü
ü)3R2R1R1(c3R
4.1.18 R1Z27
How these devices work:
● Analogous protection device with the setting R, the measurement range c and the angle phi
Measurement types supported:
● Impedance Circle
● Modified Impedance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
Zone R [Ohm] c [1] Angle phi [°]
1 1.0000 to 2.50000 (step of 0.0001) 0.5, 1.0, 2.0, 5.0, 20.0 or 50.0 60.0, 65.0, 70.0, 75.0 or 80.0
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is either an impedance circle or a modified impedance circle.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
PSS SINCAL Protection Coordination Manual SIEMENS
Protection Device Settings
April 2010 86
0,1
Iü n
int
For each zone, the resistance potentiometer must be assigned continuous values. The
measurement range can be entered individually for each zone. Set the diameter of the circle of the
respective measurement type. The primary value for R is calculated from
intcurr
voltsecpri üü
üRcR
4.1.19 RD10
How these devices work:
● Analogous protection device with the setting R and the measurement range c
Measurement types supported:
● Impedance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] c [1]
1 0.25000 to 6.25000 (step of 0.00001) 1.0, 4.0 or 8.0
2 - " - Such as c1
3 - " - - " -
IP - " - - " -
PP - " - - " -
5 ampere rated current
Zone R [Ohm] c [1]
1 0.05000 to 1.25000 (step of 0.00001) 1.0, 4.0 or 8.0
2 - " - Such as c1
3 - " - - " -
IP - " - - " -
PP - " - - " -
The tripping area is an impedance circle.
Procedural Simulation
For each zone, the resistance potentiometer must be assigned continuous values. The primary
value for R is calculated from
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Protection Device Settings
April 2010 87
curr
voltsecpri ü
üRcR
4.1.20 REL316
How these devices work:
● Digital protection device with settings R and X
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 2 ampere
● 5 ampere
1 or 2 ampere rated current
Zone R [Ohm] X [Ohm]
1 0.01 to 300.00 (step of 0.01) 0.01 to 300.00 (step of 0.01)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
5 ampere rated current
Zone R [Ohm] X [Ohm]
1 0.001 to 30.000 (step of 0.001) 0.001 to 30.000 (step of 0.001)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
The tripping area is a rectangular impedance quadrilateral.
Procedural Simulation
The primary value for R and X is calculated from
curr
voltsecpri ü
üRR
or
curr
voltsecpri ü
üXX
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Protection Device Settings
April 2010 88
4.1.21 REL521 and REL561
How these devices work:
● Digital protection devices with settings R and X
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] X [Ohm]
1 0.10 to 400.00 (step of 0.01) 0.10 to 400.00 (step of 0.01)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
5 ampere rated current
Zone R [Ohm] X [Ohm]
1 0.02 to 80.00 (step of 0.01) 0.02 to 80.00 (step of 0.01)
2 - " - - " -
3 - " - - " -
IP - " - - " -
PP - " - - " -
The tripping area is a rectangular impedance quadrilateral.
Procedural Simulation
The primary value for R and X is calculated from
curr
voltsecpri ü
üRR
or
curr
voltsecpri ü
üXX
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Protection Device Settings
April 2010 89
4.1.22 SD124
How these devices work:
● Analogous protection device with the setting R, the measurement range c and the angle phi
Measurement types supported:
● Impedance Circle
● Modified Impedance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] c [1] Angle phi [°]
1 1.00000 to 28.00000 (step of 0.00001) 0.25, 1.00 or 2.00 10.00 to 90.00 (step of 0.01)
2 - " - Such as c1 Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
5 ampere rated current
Zone R [Ohm] c [1] Angle phi [°]
1 0.20000 to 5.60000 (step of 0.00001) 0.25, 1.00 or 2.00 10.00 to 90.00 (step of 0.01)
2 - " - Such as c1 Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
The tripping area is either an impedance circle or a modified impedance circle.
Procedural Simulation
For each zone, the resistance potentiometer must be assigned continuous values. Set the radius of
the circle of the respective measurement type. The primary value for R is calculated from
curr
voltsecpri ü
üRcR
PSS SINCAL Protection Coordination Manual SIEMENS
Protection Device Settings
April 2010 90
4.1.23 SD135
How these devices work:
● Digital protection device with the setting R, the measurement range c and the angle phi
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] c [1] Angle phi [°]
1 1.00000 to 10.00000 (step of 0.00001) 0.1, 1.0 and 6.0 72
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP 1.20, 1.35 or 1.50 Such as c1 - " -
PP - " - - " - - " -
5 ampere rated current
Zone R [Ohm] c [1] Angle phi [°]
1 1.00000 to 10.00000 (step of 0.00001) 0.02, 0.20 and 1.20 72
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP 1.20, 1.35 or 1.50 Such as c1 - " -
PP - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a diamond-shaped impedance quadrilateral.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
PSS SINCAL calculates the primary value for R and X from the setting Z and the angle phi/2.
2sin
üü
üZcX
intcurr
voltsecpri
or
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)tan(X2
cosüü
üZcR
priintcurr
voltsecpri
4.1.24 SD135A
How these devices work:
● Digital protection device with the setting R, the measurement range c and the angle phi
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
Zone Z [Ohm] c [1] Angle phi [°]
1 1.00000 to 10.00000 (step of 0.00001) 0.1, 1.0 and 10.0 72
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP 1.20, 1.35, 1.50, 2.00 or 3.00 Such as c1 - " -
PP - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a diamond-shaped impedance quadrilateral.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
PSS SINCAL calculates the primary value for R and X from the setting Z and the angle phi/2.
2sin
üü
üZcX
intcurr
voltsecpri
or
)tan(X2
cosüü
üZcR
priintcurr
voltsecpri
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4.1.25 SD14, SD14A and SD14B
How these devices work:
● Analogous protection devices with the setting R and the measurement range c
Measurement types supported:
● Impedance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] c [1]
1 0.50000 to 12.50000 (step of 0.00001) 0.5, 1.0 or 4.0
2 - " - Such as c1
3 - " - - " -
IP - " - - " -
PP - " - - " -
5 ampere rated current
Zone R [Ohm] c [1]
1 0.10000 to 2.50000 (step of 0.00001) 0.5, 1.0 or 4.0
2 - " - Such as c1
3 - " - - " -
IP - " - - " -
PP - " - - " -
The tripping area is an impedance circle.
Procedural Simulation
For each zone, the resistance potentiometer must be assigned continuous values. Set the radius of
the circle of the respective measurement type. The primary value for R is calculated from
curr
voltsecpri ü
üRcR
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4.1.26 SD34A
How these devices work:
● Analogous protection device with the setting R, the measurement range c and the angle phi
Measurement types supported:
● Impedance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
1 ampere rated current
Zone R [Ohm] c [1] Angle phi [°]
1 0.50000 to 13.0000 (step of 0.00001) 0.5, 1.0 or 4.0 10.0000 to 87.0000 (step of 0.0001)
2 - " - Such as c1 Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
5 ampere rated current
Zone R [Ohm] c [1] Angle phi [°]
1 0.10000 to 2.6000 (step of 0.00001) 0.5, 1.0 or 4.0 10.0000 to 87.0000 (step of 0.0001)
2 - " - Such as c1 Such as phi1
3 - " - - " - - " -
IP - " - - " - - " -
PP - " - - " - - " -
The tripping area is an impedance circle.
Procedural Simulation
For each zone, the resistance potentiometer must be assigned continuous values. Set the radius of
the circle of the respective measurement type. The primary value for R is calculated from
curr
voltsecpri ü
üRcR
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4.1.27 SD35
How these devices work:
● Digital protection devices with the setting Z, the measurement range c and the angle phi
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
Zone Z [Ohm] c [1] Angle phi [°]
1 1.00000 to 10.00000 (step of 0.00001) 0.1, 1.0 and 6.0 90
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP 1.20, 1.35 or 1.50 Such as c1 - " -
PP - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a diamond-shaped impedance quadrilateral.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
PSS SINCAL calculates the primary value for R and X from the setting Z and the angle phi/2.
2sin
üü
üZcX
intcurr
voltsecpri
or
2cos
üü
üZcR
intcurr
voltsecpri
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4.1.28 SD35A and SD35C
How these devices work:
● Digital protection devices with the setting Z, the measurement range c and the angle phi
Measurement types supported:
● Impedance Quadrilateral
Rated currents supported:
● 1 ampere
● 5 ampere
Zone Z [Ohm] c [1] Angle phi [°]
1 1.00000 to 10.00000 (step of 0.00001) 0.1, 1.0 and 10.0 90
2 - " - - " - Such as phi1
3 - " - - " - - " -
IP 1.20, 1.35 or 1.50 Such as c1 - " -
PP - " - - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is a diamond-shaped impedance quadrilateral.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
PSS SINCAL calculates the primary value for R and X from the setting Z and the angle phi/2.
2sin
üü
üZcX
intcurr
voltsecpri
or
2cos
üü
üZcR
intcurr
voltsecpri
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4.1.29 SD36
How these devices work:
● Analogous protection device with the setting R and the angle phi
Measurement types supported:
● Impedance Circle
Rated currents supported:
● 1 ampere
● 5 ampere
Zone R [Ohm] Angle phi [°]
1 0.10000 to 99.99000 (step of 0.00001) 10.00 to 87.00 (step of 0.01)
2 - " - Such as phi1
3 - " - - " -
IP - " - - " -
PP - " - - " -
The setting range is true for devices with 1A rated current and for devices with 5A rated current.
The tripping area is an impedance circle.
Procedural Simulation
PSS SINCAL determines an internal transformer factor using the rated current with
0,1
Iü n
int
For each zone, the resistance potentiometer must be assigned continuous values. Set the radius of
the circle of the respective measurement type. The primary value for R is calculated from
intcurr
voltsecpri üü
üRR
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4.2 Calculation Method
The task of this simulation procedure is to determine the settings for distance protection devices.
PSS SINCAL first uses the protection devices and protection device types in the network to
calculate minimum network impedance using a solution strategy.
Since there are different concepts or philosophies for determining primary network impedance
settings for protection devices, these are implemented as solution strategies in the simulation
procedure.
Currently PSS SINCAL can use the following solution strategies to determine network impedance:
● DISTAL Strategy:
This strategy is based on DISTAL. The distance protection devices are set according to
absolute selectivity.
● Line Impedance Strategy:
This strategy determines the impedance areas of protection devices and their settings from the
sum of the line impedances in the protection zones.
● Line Impedance Strategy Connected:
This strategy determines the settings for protection devices from line impedances in the
network.
● Medium-Voltage Network Strategy:
This strategy determines the impedance areas of protection devices and their settings from
loop impedances in the protection zones.
PSS SINCAL uses time sequence factors to calculate the primary bend impedance from the
primary network impedance. The primary bend impedance can also be entered directly by the user.
PSS SINCAL uses transformers, protection device types and the primary bend impedance in the
network to calculate the secondary values actually set at the protection devices. PSS SINCAL
always rounds off the settings to the next possible lower setting.
Protection route simulation is a way to determine whether the tripping behavior you want can
actually be achieved with the settings that have been calculated.
All strategies that determine tripping times are identical to calculating impedance. PSS SINCAL
uses preferred tripping times, tripping distance and the tripping times of the subordinate protection
devices to calculate tripping time.
4.2.1 Entries for Determining Impedance
Entries in Calculation Settings, Network Levels and protection device data define how
PSS SINCAL calculates primary network impedance data.
Defining with Protection Device Data
If the selective grading factor – zone 2 is greater than 100 percent, PSS SINCAL uses the
primary impedance from Zone 1.
If the selective grading factor – zone 3 is greater than 100 percent, PSS SINCAL uses the
maximum network impedance from Zone 2.
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If the directional final time of the protection device is smaller than or equal to the tripping time of a
particular zone, PSS SINCAL uses the primary impedance of the previous zone. This entry has
higher priority than the entry for selective tripping factors.
General Definitions
PSS SINCAL uses the smallest impedance up to the location of the next protection device as the
primary impedance from Zone 1. If the time difference between the tripping zone of the current
protection device and that of the following protection device is greater than the minimum selective
tripping, PSS SINCAL calculates the selective tripping factor for this zone. This means that this
zone has an effect that goes beyond the next protection device.
OC protection devices at a transformer limit the protection zone. PSS SINCAL does not, however,
use the impedance up to this network point to determine the smallest impedance from Zone 1.
PSS SINCAL uses the small impedance up to the bend of Zone 1 or Zone 2 from the next
protection device as the primary impedance for Zone 2 or Zone 3, if the bend is located in Zone 2
or Zone 3.
If the bend impedance of the second or third level is less than that of the preceding level,
PSS SINCAL uses the impedance of the preceding level to calculate the settings.
If the tripping time of a level is less than or equal to the tripping time for directional current
energizing, PSS SINCAL sets the level equal to the prior level.
Defining with Calculation Settings
Protection Settings – Calculation Settings determine the:
● Strategy used to calculate primary network impedance,
● Shortest distance of the second protection zone,
● Calculation sequence for the tripping levels,
● Additional information used to calculate primary network impedance
● Delay times
Treatment of Transformers
The attribute for Treatment of Transformers in the calculation settings for Protection Settings
influences the protection zone in calculations for primary network impedance. PSS SINCAL
provides the following options:
● Consider transformers
● Ignore radial transformers
● Ignore transformers
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In the network topology below the first protection device depends on the consideration of
transformers.
Illustration: Network topology depending on user input
With Consider transformers, all network elements remain in the protection zone.
Illustration: Protection zone when transformers are considered
Ignore radial transformers ignores all transformers at the end of a radial network if there is no
supply source.
Illustration: Protection zone without radial transformers
G
G
G
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Ignore transformers ignores all transformers.
Illustration: Protection zone without transformers
Treatment of Supply Nodes
The attribute for Treatment of Supply Nodes in the calculation settings for Protection Settings
influences the protection zone in calculations for primary network impedance. PSS SINCAL
provides the following options:
● None
● Slack node
● Slack node and transformer
● Slack and transformer opposite node
In the network topology below the first protection device depends on the treatment of supply nodes.
Illustration: Network topology with direct supply source depending on user input
Without special treatment all network elements remain in the protection zone. The protection
device in the parallel feed limits the protection zone. The protection device is graded according to
what has been entered for the individual zones.
Illustration: Protection zone without special treatment of supply nodes
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When a slack node limits the protection zone, the protection zone ends at this node. The
remaining network area is a radial network. The protection device is graded according to what has
been entered for radial lines.
Illustration: Protection zone with limit at slack nodes
Since the supply source is attached directly at the network, any further setting possibilities will
create the same protection zone as if limited by the slack node. There needs to be a feed by a
transformer to have additional possibilities.
Illustration: Transformer-fed network topology depending on user input
When slack node and transformer limit the protection zone, the protection zone ends at these
nodes or elements. The protection zone ends behind the transformer or at the protection device at
the parallel feeder. The protection device is graded according to what has been entered for
individual zones.
Illustration: Protection zone with limit at slack node and transformer
When the slack and transformer opposite node limits the protection zone, the protection zone
ends at these nodes or elements. The remaining network area is a radial network. The protection
device is graded according to what has been entered for radial lines.
Illustration: Protection zone with limit at slack node and transformer opposite node
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Delay Times
PSS SINCAL uses delay times as preferential tripping times, if the tripping time of the level is 0.0
seconds and the tripping distance is kept.
If the tripping distance is greater than the tripping time entered in the minimum delay times, the
tripping time of the second level is set to the desired tripping time.
Example: Determining times when minimum tripping time is undercut
If the tripping distance is smaller than the tripping time entered in the minimum delay times, the
time of the second level is set to the tripping time of the first level of the following protection device
plus the minimum tripping time. The tripping time of the second level must be more than the
desired tripping time.
Example: Determining times when the minimum tripping time is undercut
Defining with Network Level Data
The network level defines the arcing reserve for individual voltage levels and for individual
measurement types. Depending on what has been entered, PSS SINCAL calculates the arcing
reserve before it determines the settings for bend impedance.
Factor R from X
kkRkkSetjX)X(absfRZ
Z
t
t21 t11
t12 = t21 + ts
ts
tv1
tv2
Z1 Z2
Z
t
t21 t11
t12 = tv2
ts
tv1
tv2
Z1 Z2
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R Arc (primary)
kLBkkSetjXRRZ
Minimum R/X
for Rk/jXk < Minimum R/X:
kkkSetjXX/RXZ
for Rk/jXk ≥ Minimum R/X:
kkkSetjXRZ
ZkSet … Bend impedance to determine setting
Rk … Bend resistance according to strategy
Xk … Bend reactance according to strategy
RLB … Arcing resistance
R/X … Minimum value for R/X ratio
fR … Factor for resistance
4.2.2 Type of Measurement
This is the impedance area (R/X) that can be set at the protection device. Depending on the type of
distance protection device, PSS SINCAL supports different types of measurement – and thus
impedance areas.
Older protection devices work in the same way and have a circular tripping area. Newer protection
devices work digitally and can recreate both a circular-shaped tripping area and a quadrilateral-
shaped tripping area.
PSS SINCAL provides the following types of measurement and impedance areas.
● Analogous Impedance Measurement – Impedance Circle
● Analogous Measurement of Mixed Impedance – Modified Impedance Circle
● Analogous Conductance Measurement – Conductance Circle
● Digital Quadrilateral – Impedance Quadrilateral (with/without Entering R/X > 1)
● Digital Reactance Measurement – Reactance Quadrilateral
● Digital MHO – MHO Circle
● Digital MHO Polarized – MHO Circle Polarized
When it calculates settings for distance protection devices, PSS SINCAL constructs simplified
areas from bend impedance and then uses the available settings to construct an area as similar to
this as possible at the protection devices themselves.
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Summary of important formulas for calculating the settings:
Formula sign Description
R Resistance
X Reactance
22 XRZ Impedance
R
XRZ
G
1 2
k Conductance (reciprocal conductance calculated as resistance)
c Measurement range
Impedance Circle
Impedance circles have their center at the origin of the coordinate of the R/X level.
As the smallest primary network impedance, PSS SINCAL uses the one producing the smallest the
smallest absolute value.
22
volt
curr XRü
ü
c
2r
or
c
Z2r sec
Illustration: Impedance area
Modified Impedance Circle
Modified impedance circles have their diameter on the R axis in the R/X level and passing through
the x-axis at the bend reactance.
As the smallest primary network impedance, PSS SINCAL uses the one producing the smallest
absolute value.
X05,1ü
ü
c
2r
volt
curr
X
R
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or
c
X1,2r sec
Illustration: Modified impedance area
Conductance Circle
Conductance circles have their diameter on the R axis in the R/X level and touching the x-axis.
As the smallest primary network impedance, PSS SINCAL uses the one producing the smallest
conductance circle.
PSS SINCAL determines the radius of the conductance circle as follows:
R
XR
ü
ü
c
1r
2
volt
curr
or
c
secZr k
Illustration: Conductance area
X
R
X
R
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Impedance Quadrilateral
This describes the impedance area with a quadrilateral. Entering the angle phi changes the shape
of the R/X area.
When PSS SINCAL determines the setting. it sees the impedance quadrilateral as a simplified
rectangle. If it can have an angle, PSS SINCAL uses the angle of the bend impedance of the first
level as the setting for distorting the quadrilateral.
As the smallest primary network impedance, PSS SINCAL uses the one producing the smallest
reactance value.
Illustration: Impedance quadrilateral
Reactance Quadrilateral
The reactance quadrilateral is a rectangle in the R/X level that has a prescribed X Value. The R
direction has no limit. The largest value becomes the R value. PSS SINCAL automatically adjusts
the reactance quadrilateral during protection simulation.
As the smallest primary network impedance, PSS SINCAL uses the one producing the smallest
reactance value.
Illustration: Reactance quadrilateral
X
R
X
R
Z
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MHO Circle
MHO circles pass through the origin of the coordinate and have their diameter on the straight line.
PSS SINCAL uses the angle of the bend impedance of the first level as the angle of the straight
line.
As the smallest primary network impedance, PSS SINCAL uses the one producing the smallest
MHO circle with the straight line.
To calculate the MHO circle from impedance with R and X, a straight line, normally at the
impedance indicator, has to pass through the point R/X in the R/X level. The intersecting point
becomes the diameter of the MHO circle.
Illustration: MHO circle – forward
Illustration: MHO circle – backward
MHO Circle Polarized
The polarized MHO circle is a circle based on the MHO circle. The polarization increases or
decreases the circle in the direction opposite to the fault.
PSS SINCAL always uses the pre-fault voltage to calculate polarization voltage according to
following formula:
prepreactprepVkV)k0,1(V
Vp … Polarization voltage
X
R
Z
X
R
Z
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kpre … Setting for evaluation factor for pre-fault polarization
Vact … Current voltage of the impedance loop
Vpre … Pre-fault voltage of the impedance loop
The setting for the evaluation factor for pre-fault polarization is for all levels. PSS SINCAL
calculates any change in impedance from the polarization voltage and the current as follows:
act
ppre I
VZ
Vp … Polarization voltage
Iact … Present current of the impedance loop
Zpre … Change in impedance at pre-fault voltage polarization
As the smallest primary network impedance, PSS SINCAL uses the one producing the smallest
unpolarized MHO circle with the straight line.
To calculate the unpolarized MHO circle from impedance with R and X, a straight line that is
normally to the impedance indicator has to pass through the point R/X in the R/X level. The
intersecting point becomes the diameter of the MHO circuit.
Illustration: MHO circle – forward – forward fault
Illustration: MHO circle – forward – backward fault
X
R
Z
Zv
X
R
Z
Zv
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4.2.3 Selective Grading Factors
Impedance characteristics are set in the protection device depending on circuit breaker locations
and their selective protection zones in the network. Tripping is initiated if the measured impedance
is within the set characteristic and after the corresponding delay time has elapsed.
Tripping diagrams with impedance-time characteristics provide a good method to visualize
protection device settings.
The selective grading factors determine the reach of the protection zones, based on a percentage
value of the line impedance.
Illustration: Selective grading factors
If the zone no longer has any subordinate protection device, PSS SINCAL replaces the grading
factor of the zone (st1, st2, and st3) with the grading factor for stub cables (stStich).
Zone 1
1L1
1RZ
100
stZ
Zone 2
100
st
100
stZZZ 21
2L1L2R
Zone 3
100
st
100
st
100
stZZZZ 321
3L2L1L3R
Auto-Reclosure
100
stZZ errint
1Lerrint
ZL1 ZL2 ZL3
ZR1
ZR2
ZR3
ZR1'
ZR2'
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Teleprotection
100
stZZ
comp1Lcomp
Recommended Selective Grading Factors
%90ststst321
%120ststcomperrint
Zones of the Next Protection Device
100
stZZ 1
2L'1R
100
st
100
stZZZ 21
3L2L'2R
4.2.4 DISTAL Strategy
The DISTAL strategy sets the protection devices according to absolute selectivity.
The following are true:
● PSS SINCAL observes all protection devices in the direction of the line.
● Except for the branch with the protection device, all branches leading away from protection
devices are disconnected.
● A generator is created at the protection device location to determine the network impedance of
the protection device.
● The real generators in the network can either be deactivated or considered in the calculations.
● A minimum value of R/X is entered for impedance quadrilaterals to assure there will be no
unfavorable impedance areas (too long and narrow).
Types of Protection Zones
Distance protection devices determine the fault impedance from the line voltage and current at the
location.
Protection devices can measure the fault removal correctly only if the line connecting the protection
device to the fault location is an unbranched radial line or if there is a tree with only one supply
source at the location.
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Illustration: Protection zone as a radial line
4321K
RZZZZ
I
VZ
Illustration: Protection zone as a tree
321K
RZZZ
I
VZ
Each parallel path increases the range of the protection device, and the protection device "sees"
the fault as being closer.
Illustration: Protection zone with parallel path
P2
P21
P2
P21R ZZ
ZZZ
ZZ
ZZZZ
Each intermediate supply source (between the protection device and fault location) shortens the
range of the protection device; i.e. the protection device "sees" the fault as being farther away.
Z1
ZP
Z2
Z1
Z3 Z2
JK
Z1
Z3 Z2
Z4
JK
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Illustration: Protection zone with intermediate supply source
22111Z)II(ZIV
21
211
1R
ZI
IIZ
I
VZ
Normally, a meshed network has several supply sources. The following diagram shows a path in a
meshed network where the range of the protection devices at the beginning of the route is to be
checked:
Illustration: Protection zone in a meshed network
1 2
3 4
~
J2 J1
V
~
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Networks can be converted to the form below:
Illustration: Converted meshed network
Normally meshed networks have:
● A supply source with pre-reactance at each station
● Parallel connections between all stations
All supply sources and parallel connections must be considered to find the exact setting of the
protection device.
This setting is correct only for this basic network condition.
Changing feed ratios or switching lines ON/OFF, however, does change the impedance measured
by the protection device. Particularly when intermediate supply sources are turned OFF, the
protection device measures "too far". This means there is no selective tripping, and the devices are
not turned OFF properly.
To assure selective tripping for all feeding and switching conditions, you need to select the network
condition where the protection device measures farthest. This means the protection device can
only measure distances that are shorter than this and never measures beyond the permissible
selective tripping limit.
Protection devices have maximum range:
● If you have eliminated all intermediate supply sources that might shorten the range (as
explained above)
● If there is a supply source at the protection device
● If you have considered all parallel paths (parallel paths starting from Station 1 are not
considered since they are an intermediate supply source and NOT a parallel path for the short
circuit current running through the protection device)
1 2 3 4
~ ~ ~ ~
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The following is a network diagram that has been converted to determine the settings of Protection
Device 1:
Illustration: Converted network diagram
ZP1, ZP2 and ZP3 are replacement impedances for the entire parallel subnetwork. (Parallel resistors
of the subordinate network level are not considered since relatively high-resistance dead-end
transformers block them).
These tripping resistors guarantee the highest degree of selectivity. Even in worst-case network
switching and feeding scenarios, tripping will be selective (worst case-selective tripping).
Zone 2 must go beyond the remote station to include busbar faults with arcs. This is particularly
important for busbars that are not protected.
Sequence for Calculating the Tripping Zones
Calculating Zone 1
Zone 1 can be calculated exactly. Since accurate calculations are unnecessary, a selective grading
factor of 90% is recommended.
Calculating Zone 2
In the next zone, PSS SINCAL first considers all the parallel resistors. Then it checks whether the
zone goes beyond the following station by a minimum percentage. This percentage can be set in
the Calculation Settings. If Zone 2 does go beyond the next station by this amount, PSS SINCAL
displays a warning message.
This assures a good compromise between selectivity and tripping. PSS SINCAL prints a log of the
actual range of Zone 2 as a percentage of the line with the protection device. This log should be
checked if PSS SINCAL displays a warning message.
Calculating Zone 3 (Normal with Grading Factor < 100 %)
The Zone 3 checks all the parallel resistors for selectivity. PSS SINCAL automatically shuts down
any line segments that Zone 3 does not reach. Selectivity is emphasized. Very rarely, however, a
protection device or switch can fail in the meshed network, and there can be somewhat longer
tripping times.
1 2 3 4
ZP1
ZP3
ZP2
~
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Calculating Zone 3 (Normal with Grading Factor ≥ 100 %)
The Zone 3 has to reach past the second station away to avert larger network shutdowns.
Illustration: Calculating Zone 3
3max213Rst)ZZ(Z
Here some additional lines can be turned OFF to prevent a larger network shutdown.
Calculating Zone 3 like Zone 2
The same impedance setting should be used for the Zone 2 and Zone 3.
4.2.5 Line Impedance Strategy
PSS SINCAL uses the line impedances in the network to calculate the settings of protection
devices.
The following is true:
● PSS SINCAL observes all protection devices in the direction of the line.
● Parallel paths are observed separately.
● Ends of protection zones are observed separately.
● For the settings, PSS SINCAL uses the impedance sum that creates the smallest conductance
circle.
Types of Protection Zones
To determine the settings, PSS SINCAL simply adds up all the line impedances, similar to the way
many energy suppliers do in real networks.
Illustration: Protection zone as a spur
Z1
Z3 Z2
Z4
Z21 Z31
ZR3
Z22
Z23
Z32
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4321RZZZZZ
Illustration: Protection zone as a tree
4211RZZZZ
5212RZZZZ
6313RZZZZ
7314RZZZZ
Illustration: Protection zone with a parallel path
211RZZZ
312RZZZ
Determining the Conductance Circle
The conductance, or mho, circle is one whose diameter touches the r axis in the R/X level and the
x axis. To determine the conductance circle from impedance with R and X, a straight line that
normally goes to the impedance index through the point R/X in the R/X level has to intersect with
the r axis. The point of intersection is used for the diameter of the conductance circle.
Z1 Z2
Z3
Z1
Z6 Z3
Z4
Z5
Z7
Z2
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Illustration: Determining the diameter of a conductance circle
4.2.6 Line Impedance Strategy Connected
PSS SINCAL uses the line impedances connected in the network to calculate the settings of
protection devices.
The following is true:
● PSS SINCAL closes all switches
● PSS SINCAL observes all protection devices in the direction of the line
● Parallel paths are observed separately
● Ends of protection zones are observed separately
● For the settings, PSS SINCAL uses the impedance sum that creates the smallest conductance
circle.
The only difference between this strategy and Line Impedance Strategy is that the switches are
closed.
4.2.7 Medium-Voltage Network Strategy
Medium-Voltage Network Strategy uses minimal loop impedance at the protection device to
determine protection device settings.
The following is true:
● PSS SINCAL observes all protection devices in the direction of the line.
● No modifications are made to the network.
● If there is a short circuit in the protection zone, there must be current and voltage at the
protection device.
● To determine minimum loop impedances for individual zones, PSS SINCAL calculates one
short circuit each directly behind every protection device limiting the protection zone.
● Entering a minimum value of R/X for impedance quadrilaterals assures ideal impedance areas
that are neither too narrow nor too high.
Types of Protection Zones
Distance protection devices investigate the fault impedance from line voltage and current found at
the location.
X
R d
ZRi
.
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For protection devices to measure the impedance up to the fault location correctly, the current from
the protection device has to create the remaining voltage at the protection device. If this does not
happen (i.e., because there are parallel paths), the loop impedance will increase.
Protection Zone – Zone 1 (without Parallel Paths to Create the Remaining Voltage)
The example below illustrates that the network acts as a radial network for the protection device.
This is true for all faults in the protection zone during the first time period.
Illustration: Fault at a common node
2211FIZIZV
11
11
1
F1Loop
ZI
IZ
I
UZ
22
22
2
F2Loop
ZI
IZ
I
UZ
Since both of these supply the same voltage, the protection device registers the correct impedance
up to the fault location.
Illustration: Fault in the middle of a parallel line
2122211FZI)ZZ(IV
2211
2211
1
F1Loop
ZZI
)ZZ(I
I
VZ
212
212
2
F2Loop
ZI
ZI
I
VZ
VF, IF
Z1 I1
IF
Z21 I2
Z3
Z22
IF
VF, IF
Z1 I1
Z2 I2
Z3
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Protection Zone – Zone 2 (with Parallel Paths to Create the Remaining Voltage)
In the example below, note that there is no increase in loop impedance before the second time
period.
Illustration: Fault at the end of the protection zone
3F223F11FZIZIZIZIV
31
F1
1
3F11
1
F1Loop
ZI
IZ
I
ZIZI
I
VZ
32
F2
2
3F22
2
F2Loop
ZI
IZ
I
ZIZI
I
VZ
21FIII
31
213
1
2111Loop
ZI
I1ZZ
I
IIZZ
32
123
2
2122Loop
ZI
I1ZZ
I
IIZZ
The loop impedance up to the fault location is no longer equal to the sum of the line impedances.
Since the fault current is divided between Lines 1 and 2, the registered loop impedance must be
greater than the sum of the line impedances.
VF, IF
Z1 I1
IF
Z2 I2
Z3
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4.3 Results of Settings Calculations
This simulation procedure generates results as settings calculated for distance protection devices
and diagrams (selective tripping schedules).
Calculated Settings
Illustration: Settings calculated for distance protection devices
PSS SINCAL lists the settings from the calculations in the data output form, If necessary, they can
also be used directly as input parameters in the settings. For a detailed description of how this is
done, see the example in Protection Device Settings.
Diagrams
For each protection device, PSS SINCAL generates two grading diagrams. These can be called up
with DI Device Settings – Grading Diagram (Z/t or X/t). The diagrams also have subordinate
protection devices in the protection zone. These diagrams show tripping behavior of the protection
devices over a period of time in dependence on the bend impedance calculated.
The bends in the diagram are the intersecting points (Z or X) of the impedance area with lines
through the origin of the coordinate and the bend that has been calculated. If directional current
energizing has been entered, PSS SINCAL will show this after the last available level.
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Since the bend impedance does not have to agree with the registered loop impedance, this tripping
behavior purely prognostic. Protection route simulation is used to determine whether the desired
tripping behavior can actually be achieved. If the registered loop impedance of the protection
device is not the same as the calculated bend impedance, this will produce different tripping
behavior in protection route simulation. In this case, protection device settings will need to be
calculated again using a different strategy, or modified by hand until the desired tripping behavior is
achieved.
Illustration: Diagram of DI Device Settings – Grading Diagram
Sometimes you also need to generate selective tripping diagrams for documentation without
determining the settings. Click Calculate – Protection Device Coordination – DI Device –
Charts in the menu to start this function.
4.4 Hints and Cautions
Note the following:
● The procedure does NOT let you automatically switch measurement types. If the distance
protection device cannot be set with this type, PSS SINCAL aborts the calculations and
displays an error message. This also happens if a distance protection device supports different
types of measurement and the required setting could be done with another type of
measurement.
● If Zone 2 is less than Zone 1 PSS SINCAL gives Zone 2 the same setting as Zone 1.
● If Zone 3 is less than Zone 2 PSS SINCAL gives Zone 3 the same setting as Zone 2.
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5. Fault Detection
This procedure localizes a fault at a protection device, determining the precise position of the fault
in the supply network.
Modern protection devices save the impedance that caused the tripping when there is a fault.
These values let you calculate the position of the fault in the network.
Calculation Method
If there is a fault at a protection device (see the section on Protection Location in the chapter on
Data Description in the Input Data Manual), enter the impedances registered by the protection
device.
PSS SINCAL then goes through the network in the direction of the line looking for every protection
device that has these data. This search stops at the next or second to the next protection device in
the same direction.
Illustration: Principle of fault detection
PSS SINCAL calculates short circuits along these lines, which have been divided up depending on
detection accuracy. If the impedance measured is between the registered impedance of the
following two short circuit calculations, PSS SINCAL records the impedance as a hit. It also records
the distance from the starting node.
In the above example, the fault is in Line L2. The impedance (ZR) for the fault was registered at the
protection device. The simulation procedure indicates two possible locations of the fault – in Lines
L2 and L3 – for the impedance registered.
Fault detection accuracy can be set in the Calculation Settings. Note that higher detection accuracy
increases calculation time.
L1
L3
L2
ZR
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Results of Fault Detection
PSS SINCAL displays all the results in the message box, so you can identify the network elements
that have faults (see the chapter on Messages in the System Manual).
Message in the example:
● Fault detection by one protection device(s) between 350.0 and 400.0 meters from the starting
node. (Line: L16, Protection Device: Dist in S9)
This message tells you how many protection devices registered the fault. It also lists the line where
the fault is presumably located, the distance from the fault to the starting node and the protection
devices that have registered the fault.
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6. Dimensioning
PSS SINCAL calculates the minimum one-phase short circuit currents in low-voltage networks
according to VDE 0102 Part 2/11.75 and determines the maximum permissible amount of rated
fuse current for fuses.
A differentiation must be made between a normal circuit-breaking examination and a circuit-
breaking examination that is made after the load flow has been calculated. In the latter case, load
currents from the load flow calculations produces the minimum rated fuse currents and examining
the cut-off conditions produces the maximum rated fuse current. If the load current from the load
flow calculations is greater than the permissible rated fuse current after the circuit-breaking
condition, PSS SINCAL records this in the output log.
Only fuses in network areas with a rated voltage less than 1 kV are accepted. PSS SINCAL does
not check branches with short circuit currents less than 6 A. PSS SINCAL only accepts fuse areas
with a maximum of 3 limited fuses.
Dimensioning Calculation Procedures
Illustration: Sequence diagram
Unload and check all network data
Create subnetwork using transformers
Check tripping condition
Have all fuse areas been calculated?
Yes
No
Determine fuse areas
Determine minimum short circuit power
Have all subnetworks been calculated?
Prepare results
Yes
No
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6.1 Calculation Methods
Creating Subnetworks
Typically, networks are medium- and low-voltage networks. These low-voltage networks are
normally made up of several subnetworks.
Illustration: Network with various subnetworks
Since medium-voltage networks are recreated by the ensuing short circuit power at the transformer
on the high-voltage side, they can be eliminated from the calculations. The pending short circuit
power is entered in the field Short Circuit Alternating Power of Calculation Settings.
Subnetworks can be found with the help of the network analysis in the low-voltage network. Since
the neutral-point coupling between the subnetworks is ignored, each subnetwork can be calculated
and observed separately.
The maximum permissible rated fuse current must be determined separately for each fuse in the
low-voltage network. The minimum one-phase short circuit current for each fuse area must also be
determined. A fuse area is defined as the network up to the next fuse. A fuse area is also always
limited by a fuse or stub end.
PSS SINCAL searches for the location with the minimum total one-phase short circuit current I"kmin
in each fuse area. This is the basis for Determining the Rated Fuse Current.
Low-voltage network
Subnetwork1
Subnetwork2
Subnetworkn
Medium-voltage network
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Radiating Networks
In a radiating network, the nearest fuse or the end of the line recreates the least favorable fault
location.
Illustration: Radiating network
Meshed Networks
Meshed networks are recreated here for several time periods called time steps. In the first time
step, all the fuses are still in the network and modifications to network topology have not yet been
calculated. PSS SINCAL takes fuse melting is taken into consideration in the subsequent time
steps.
Since PSS SINCAL can calculate maximum fuse areas with three limiting fuses, there is a
maximum of only three time steps:
Illustration: First time period
PSS SINCAL determines the location with the smallest one-phase total short circuit current Ik1 and
calculates.
)III(kI3N2N1N1k
IN2
Ik1
IN1
IN3
Trafo
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Illustration: Second time period
In the second time step, PSS SINCAL recalculates the location with the smallest current Ik again
and recalculates Ik.
)II(kI3N1N21k
)II(kI2N1N22k
)II(kI3N2N23k
Ik21
IN3
IN1
Ik22
IN2 IN1
Ik23
IN2
IN3
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Illustration: Third time period
In this third time step, only the stub ends and the installation locations of the fuses remain to be
checked.
1N31kIkI
2N32kIkI
3N33kIkI
Location of Minimum Total Short Circuit Current
The location that produces the minimum total short circuit current is easily found for radiating
networks and for the last time step for meshed networks. It is at the end of the fuse area (the stub
end or the beginning of the new fuse area).
Ik33
IN3
Ik31
IN1
Ik32
IN2
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In meshed networks, short circuits are simulated at the nodes along the lines of the fuse area,
except for the last time step. The lines are divided into several imaginary sublines. Enter the
number of short circuit locations or lines in the field Subdivisions in the Calculation Settings.
Minimum Total Short Circuit Current
The minimum initial short circuit alternating current I"k1p can be determined in the following manner
according to VDE 0102 Part 2:
01
NTp1k zz2
V95.03"I
p1k"I … Minimum one-phase total short circuit current
NTV … Rated voltage of the low-voltage side of the transformer
… Positive-phase-sequence impedance
… Zero-phase-sequence impedance
0.95 * VNT is the driving voltage for calculating minimum one-phase total short circuit current.
Enter this value in the Calculation Settings.
Determining Rated Fuse Current
PSS SINCAL determines the rated fuse current from the minimum one-phase total short circuit
current and the number of picked-up protection devices using the following criteria:
● Safety factor (factor rated current)
● Conductor cross-section
● Thermal damage – short circuit
● Thermal load time – current and large control current
● Maximum breaking time
If one of the above criteria are violated, PSS SINCAL uses the next smaller of the rated currents
possible for this type data.
Safety Factor (Factor Rated Current)
Each fuse’s safety factor (factor rated current) is found in the input data for this fuse.
1z
0z
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The following condition has to be met:
pickupNS
p1k
nI
"Ik
I"k1p … Minimum one-phase total short circuit current
k … Safety factor (rated current factor)
INS … Rated current fuse
nAnreg … Number of picked-up protection devices
Conductor Cross-Section
Depending on the conductor cross-section, the rated fuse current strengths below cannot be
exceeded at copper cables according to VDE 0636.
Rated current INArea [A] Conductor cross-section [mm2]
6 1
12 1,5
20 2,5
25 4
32 6
50 10
63 16
80 25
100 35
125 50
160 70
200 95
250 120
315 185
400 240
500 300
630 400
800 500
1000 600
1250 800
PSS SINCAL calculates all lines of a protection zone for minimum short circuit current and the
smallest cross-section for all the lines.
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The following condition has to be met:
NAreaNSII
Thermal Damage – Short Circuit
PSS SINCAL uses the characteristic curves of the type data and the minimum short circuit current
to interpolate the tripping time for each rated fuse current. Current and time are used to determine
the thermal energy I2t. If the maximum thermal energy is less than that of the network elements to
be protected, PSS SINCAL selects the next smaller rated fuse current.
The following condition has to be met:
element2
fuse2 tItI
Thermal Load Time – Current and Large Control Current
The tripping current of the protection device that is supposed to trip can, by international definition,
be only 1.45 times the current maximum load of the lines. The large control current of the
protection device has to be used as the tripping current. The current maximum load is the thermal
limit current Ith found in the line data. The table below shows the large control current from the rated
current according to VDE 0636:
Rated current INS [A] Factor for large control current fI2 [p.u.]
Up to 4 2.1
5 to 10 1.9
11 to 25 1.75
Above 25 1.6
PSS SINCAL calculates all lines of a protection zone for minimum short circuit current and the
smallest thermal limit current of all the lines.
The following condition has to be met:
2NSthflII45,1
Maximum Breaking Time According to VDE 0100
Installation networks must have a maximum breaking time of five seconds according to VDE 0100.
PSS SINCAL uses type data characteristics and minimum short circuit current to interpolate the
tripping time for each rated fuse current. If the time is more than five seconds, PSS SINCAL selects
the next smaller rated fuse current.
The following condition has to be met:
5ttripping
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7. Examples
This chapter contains examples for Protection Coordination and Creating Protection
Documentation.
7.1 Example for Protection Coordination
Below is a simple example of how Protection Coordination works. The following descriptions
show:
● Presetting Calculation Settings
● Creating Protection Devices
● Making Fault Observations
● Making Fault Events
● Determining Settings for DI Protection Devices
● Checking Tripping Behavior for Protection Devices
● Starting the Protection Calculations
● Displaying and Evaluating the Results
● Generating Protection-Route Diagrams
Basic Data
All descriptions are based on the following network.
Illustration: Protection network with input data
When you install PSS SINCAL, the program automatically provides a network ("Example Prot"),
which can be used to check the simulation procedure.
The names of protection devices in the network are chosen so that devices at the beginning and
end of a protection route all have the same name and the device at the end has a "G". In the above
example, devices "D1" and "D1G" are in the protection route between "K1" and "K3".
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To calculate protection coordination, Protection Device Coordination in the Calculate –
Methods... menu has to be activated (see Presetting Calculation Methods in the chapter on User
Interface in the User Manual).
7.1.1 Presetting Calculation Settings
In the Calculation Settings screen form, click the Protection Settings tab to set parameters for
the calculations. To open the screen form, click the menu item Calculate – Settings...
Illustration: Data screen form for Calculation Settings – Protection Settings
Important are the settings in the first part of this tab. The Strategy field sets which procedure
PSS SINCAL uses. Enter the selective grading factor you want in Sel. Grading Factor – 2nd
Zone. If the distance is less than this value, PSS SINCAL will send a warning message.
For a detailed description of all available calculation settings, see the section on Protection Settings
– Calculation Settings in the chapter on Calculation Settings in the Input Data Manual.
7.1.2 Creating Protection Devices
The following examples show only how to create and edit protection devices. The instructions
describe how real networks are created (see the chapter on Using an Example to Work on a
Network in the System Manual).
The simplest way to create protection devices is to use the pop-up menu. To open it, right-click the
terminal of that network element where you want to add the protection device.
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Illustration: Creating protection devices with the pop-up menu
Select in the pop-up menu the desired protection device type in the Insert Protection Device
menu.
PSS SINCAL displays a data input form where you enter the name of the new protection device.
Illustration: Entering the name of the protection device
For distance-protection devices, the type needs to be entered. PSS SINCAL differentiates between
"predefined" and "user defined" distance-protection devices.
A special model simulates the settings and the impedance areas of "predefined" devices.
Impedance areas describe "user defined" devices.
Click OK, and PSS SINCAL opens the screen form for protection devices.
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Illustration: Location of the protection device
The left side of the dialog box has a browser with the new distance protection device. When the
new device is selected, PSS SINCAL displays the general data at the right side of the dialog box.
General data show, among other things, where the protection device, its pre-switched current and
voltage transformer and the directional element are located. See Protection Location for a detailed
description of all the fields.
General data can also be used to turn protection devices OFF (without deleting them). This
switches Out of service ON. PSS SINCAL disregards this protection device in the calculations. A
special protection device symbol shows that this has been switched OFF.
The settings of the protection devices are both device- and type-specific. Click Settings in the
browser to display and edit them.
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Illustration: Settings for impedance protection device
This screen form is used to define individual settings for the new impedance-protection device.
With predefined distance protection devices, select the type of protection device and the type of
measurement. Also enter the selective distance factors and the tripping times.
With user-defined distance protection devices, define the impedance area.
With OC protection devices, select the protection device type from the protection device database
and enter the settings in the dialog box.
7.1.3 Making Fault Observations
Fault Observation is used to place "faults" at nodes and terminals of network elements in the
network.
Fault observation is used by the following simulation procedures:
● Protection simulation
● Multiple faults
● Stability
The simplest way to create fault observations is to use the pop-up menu. To open it, right-click the
terminal of that network element where you want to add the fault observation.
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Illustration: Creating fault observations with the pop-up menu
PSS SINCAL displays a screen form for the fault observation.
Illustration: Data screen form for Fault Observation
For a detailed description of how to enter data for fault observations, see the section on the Fault
Observation in the chapter on General Control and Input Data in the Input Data Manual.
7.1.4 Making Fault Events
Fault events let you group different fault observations. The protection coordination treat fault
observations grouped in this way as simultaneous faults.
Select Insert – Additional Data – Fault Event… in the menu to define fault events.
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Illustration: Data screen form for Fault Event
Fault events only have a Fault Event Name and an Operating State. The status specifies whether
or not PSS SINCAL considers the package in the calculations.
You can assign individual fault observations to the fault events directly in the basic data of the fault
observation. Simply select the package you want in the Fault Event field.
7.1.5 Determining Settings for DI Protection Devices
In the procedure to determine protection device settings, PSS SINCAL uses set grading factors
and delay times to calculate settings for distance protection devices in individual protection areas.
Note that PSS SINCAL only calculates time settings for distance levels when 0.0 seconds has
been entered as the tripping time for the level.
Start to Determine Settings
To start DI device settings determination, click Calculate – Protection Device Coordination – DI
Device – Settings.
If the calculations can be done without errors, PSS SINCAL displays the following dialog box.
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Illustration: Calculated Distance Protection Device Settings dialog box
This dialog box lists all the distance protection devices in the network. PSS SINCAL automatically
selects all devices that have no settings (such as Device D5 here). You can also select additional
devices from the list.
Click Details… to open a data screen form listing all the attributes of the element selected. You
can also double-click an element in the list to open this data screen form.
To simplify the selection of protection devices, PSS SINCAL provides the following control buttons:
● Select All:
Selects all the displayed protection devices in the list.
● All Calculated:
Selects protection devices that have the status Calculated.
● Deselect All:
Resets the selection at all protection devices.
When the dialog box opens, protection devices are selected that have the status No data.
Click Select to highlight the protection device in the network diagram selected in the list.
Click Apply to close the dialog box. PSS SINCAL adds the calculated settings to the protection
devices you have selected. PSS SINCAL then uses these results as input data (settings) for the
protection device(s).
This dialog box can be opened again later. You even can open this pop-up menu in a free area of
the Graphics Editor and click Results – DI-Protection Device – Settings....
Results of Settings Calculations
PSS SINCAL calculates the settings for the protection device and then displays the following
screen form:
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Illustration: Screen form for distance protection devices
The settings for protection device D5 were used, and the status in the Type of Input Data field is
Calculated.
The status of the Type of Input Data field can be:
● No data:
This protection device still has no settings and no impedance areas for PSS SINCAL to use in
the protection simulation.
● Calculated:
PSS SINCAL has calculated the settings for this protection device. They can be overwritten.
● Manual:
The settings were entered by hand. This procedure will not modify the values.
PSS SINCAL calculates the settings and displays these in Calculated for Device D5 in the
browser. Click Calculated Settings to see the calculation results. These settings are always
available, whether or not the settings are used for the particular protection device.
In addition to settings, these calculation methods also generate diagrams as selective tripping
schedules. PSS SINCAL provides these in Diagram View under Protection Device Coordination
– DI Device Settings.
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Illustration: DI device settings – grading diagram
For a description of the calculation method, see the chapter on Calculation Procedure.
7.1.6 Checking Tripping Behavior for Protection Devices
PSS SINCAL simulates the starting and tripping behavior of all protection devices in the network.
PSS SINCAL considers both distance protection and overcurrent protection devices. For a detailed
description of this procedure, see the chapter on Protection Simulation.
Prerequisites
When checking tripping behavior, faults have to be observed in the network. Fault observations
symbolize faults in the network, for which PSS SINCAL checks the protection setting accuracy.
These can be connected to any network element (see the section on Making fault observations).
7.1.7 Starting the Protection Simulation
There are two types of calculations:
● Calculating all fault observations in the network
● Calculating a fault observation using the pop-up menu
To calculate all fault observations in the network, select the following menu items:
● Calculate – Protection Device Coordination – 3-Phase Short Circuit
● Calculate – Protection Device Coordination – 2-Phase Short Circuit
● Calculate – Protection Device Coordination – 2-Phase to Ground
● Calculate – Protection Device Coordination – 1-Phase to Ground
● Calculate – Protection Device Coordination – Fault Event
To observe a fault, open the pop-up menu for this fault observation and select the desired type of
calculations in the menu item Calculation at Fault.
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Illustration: Starting protection simulation with the pop-up menu
PSS SINCAL has a special Fault Event function that lets you simulate different faults in the
network simultaneously analogous to the multiple fault calculations. Manually defined Fault Events
combine different fault observations and create a package.
7.1.8 Displaying and Evaluating the Results
PSS SINCAL calculates the settings for the protection device and then displays the following
results in the Graphics Editor.
Illustration: Protection network with results
This example shows the results of the first loop for the fault observation in Line L8.
Protection Device D5, at the beginning of the line, and Protection Device D5G, at the end of the
line, have a "+". A plus means that the settings that have been entered could trip the devices.
PSS SINCAL also displays both devices in red. This shows that both devices may also have
tripped.
PSS SINCAL uses the following colors to designate tripping and pickup:
● Red – The protection device has tripped.
● Yellow – The protection device has been picked-up within the selective tripping time.
● Green – The protection device is picked-up.
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PSS SINCAL searches for protection devices that can trip in each fault examination. These
comprise all protection devices that limit the fault going forward.
In the network diagram, PSS SINCAL marks with a "+" all protection devices that can trip. This is
independent of the current status of the protection device (not picked-up, picked-up, etc.).
In the network diagram, PSS SINCAL marks with an "x" all protection devices that are not
supposed to trip but do so.
Selection of the Results with Toolbar
PSS SINCAL has a special toolbar to simplify selecting results. In protection simulation, select the
desired fault observation and flow in this toolbar. PSS SINCAL displays these results in the network
graphics and in the protection devices dialog box.
Activate this toolbar by clicking View – Toolbars – Results.
Illustration: Results toolbar
Information in the Message Box
In addition to the results displayed in the Graphics Editor, information can be obtained from
Messages.
Illustration: Protection results in the message box
The button HTML Log displays, as an HTML log, which protection devices in the current fault
observation and loop:
● May trip
● Have tripped
● Are picked-up or not picked-up
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Results in Diagrams
In addition to the results displayed in the Graphics Editor and the information box, PSS SINCAL
generates results in diagram form. To view this information, click View – Diagram View….
Illustration: Protection results in the diagram form
The diagrams for tripping area and tripping characteristics can be combined in the browser. Select
the protection devices you want to display in the diagram. For a detailed description, see the
section on Overlay Tripping Characteristics in the chapter on Diagram View in the System Manual.
7.1.9 Generating Protection-Route Diagrams
The network and its built-in protection devices are used to generate a wide variety of diagrams,
which can be used to check the correctness of the protection setting.
To generate protection-route diagrams, click Calculate – Protection Device Coordination –
Routes. PSS SINCAL can create diagrams for 3- and 2-phase short circuits and 2- and 1-phase to
ground.
To view this information, click View – Diagram View….
The simulation procedure generates the following protection-route diagrams:
● Tripping Behavior
● Ratio Impedances (Z)
● Ratio Reactances (X)
● Impedance and Tripping Areas
Note: In the diagrams for protection devices, PSS SINCAL can generate these diagrams only when
the output in the selective grading diagram is turned ON (see the section on Protection Location in
the chapter on Data Description in the Input Data Manual).
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The calculation settings control how protection-route diagrams are displayed on the screen. You
can define, for example, the displayed protection route, using the field zones for selective
grading diagrams. For a detailed description, see the section on Protection Settings – Calculation
Settings in the chapter on Calculation Settings in the Input Data Manual.
The following diagram shows the tripping behavior of Protection Device D5.
Illustration: Tripping behavior diagram
This diagram shows the impedance of the protection route, as well as the node and additional built-
in protection devices in the x axis. The y axis contains the tripping time of the particular zone.
Protection devices that face "forward" are displayed in the diagram with negative time (i.e. below
the x axis). In the example above, these are devices D5G and D8G.
7.2 Example for Creating Protection Documentation
Below is a simple example of how Creating Protections Documentation works. The following
descriptions show:
● Selecting Grading
● Creating the Protection Documentation
● Inserting a Diagram
Basic Data
This description is based on a medium size industrial network with both OC and DI protection
devices. Generally speaking, however, protection documentation can be for any network.
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Illustration: Protection network with overcurrent protection devices
PSS SINCAL allows protection documentation for all types of elements. But if you need additional
information such as, for example, input data and limits, the network has to have overcurrent
protection devices. This is why we have included them in this example.
7.2.1 Selecting Grading
For protection documentation you first need to select a grading in an individual view. This can be
done in a number of ways, such as, for example, manually, by selecting the route, etc.
Illustration: Grading selected in the network
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7.2.2 Creating the Protection Documentation
After you have selected the grading, it is possible to create protection documentation. Click Tools –
Create Protection Documentation… in the Basic View to activate the function.
Illustration: Dialog box for Create Protection Documentation
Use the Name input field to define the name (in this case "Doc 1") for the new view.
This dialog box has all appropriate views for the documentation, i.e. PSS SINCAL lists all empty
and open views. In this example we chose the new created view.
When Create legends for protection devices is switched ON, PSS SINCAL displays
supplementary information (for range and input data) for OC protection devices of the selected
grading. You can set the layout and the distances between legends and protection devices or
modify it later in the Protection Device Legend dialog box.
The Page settings section lets the user select the desired paper format and the basic unit for the
new view.
Press OK to close the dialog box, and PSS SINCAL creates the protection documentation in the
new view.
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Illustration: Protection documentation without diagrams
7.2.3 Inserting a Diagram
Once the protection documentation is finished, you can add a diagram. Simply click Insert –
Objects – Diagrams in the menu.
Click on the position where you want to insert the diagram with the mouse to open a dialog box
where you can select a diagram.
Illustration: Dialog box for Diagrams
In this example the Station 2 diagram was selected and the dialog box was closed with OK.
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Illustration: Protection documentation with a diagram
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