Siemens SIPROTEC 7SS523 V3.2 User manual

C53000-G1176-C182-1
SIPROTEC
Distributed Busbar/ Breaker
Failure Protection
7SS522 V4.6
7SS523 V3.2
7SS525 V3.2
Manual
Preface
Table of Contents
Introduction 1
Design and Connection System 2
Getting Started 3
Configuration 4
Functions 5
Control During Operation 6
Installation and Commissioning 7
Maintenance and Repair 8
Technical Data 9
Appendix A
References
Index

Siemens Aktiengesellschaft Buch-Nr. C53000-G1176-C182-1
Exclusion of Liability
We have checked the contents of this publication and every effort has been
made to ensure that the descriptions of both hardware and software are as
accurate as possible. However, deviations from the description cannot be
completely ruled out, so that no liability can be accepted for any errors or
omissions contained in the information given.
The data in this manual are checked regularly and the necessary corrections
are included in subsequent editions. We are grateful for any improvements
that you care to suggest.
Subject to technical modifications.
Document Release 4.60.02
Copyright
Copyright  Siemens AG 2005 All Rights Reserved
Dissemination or reproduction of this document, or evaluation and commu-
nication of its contents, is not authorized except where expressly permitted.
Violations are liable for damages. All rights reserved, particularly for the pur
-
poses of patent application or trademark registration.
Registered Trademarks
DIGSI®is a registered trademark of SIEMENS AG. Other designations in
this manual may be trademarks that if used by third parties for their own pur
-
poses may violate the rights of the owner.

iii7SS52 V4 Manual
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Preface
Aim of this Manual This manual describes the functions, operation, installation, and commissioning of the
complete SIPROTEC 7SS52 V4 distributed busbar and breaker failure protection sys-
tem. In particular, you will find:
•Information on configuration of the system → Chapter 4, page 45
•Description of the system functions and their setting options → Chapter 5, page 91
•Information on control during operation →Chapter 6, page 203
•Information on installation and commissioning → Chapter 7, page 245
•Overview of technical data → Chapter 9, page 301
•and a compilation of the most important information for the experienced user
→Chapter A.1, page 328
The SIPROTEC 4 System Description /1/ deals in a general way with the manage-
ment, configuration, parameterization, operation, installation and commissioning of a
SIPROTEC 4 system.
Target audience Protection engineers, commissioners, persons who are involved in setting, testing and
maintenance of protection, automation, and control devices, as well as operation per-
sonnel in electrical plants and power stations.
Scope of validity of
this manual
This manual is valid for the complete SIPROTEC 7SS52 V4 distributed busbar and
breaker failure protection system, firmware version 4.6. The system comprises the
central unit 7SS522 V4.6 and the bay units 7SS523 V3.2 and 7SS525 V3.2. The com-
plete system will be referred to in the manual as 7SS52 V4.
Indication of Conformity
This product complies with the directive of the Council of the European Communities
on the approximation of the laws of the Member States relating to electromagnetic
compatibility (EMC Council Directive 89/336/EEC) and concerning electrical equip-
ment for use within specified voltage limits (Low-voltage directive 73/23 EEC).
This conformity has been proved by tests performed according to Article 10 of the
Council Directive in agreement with the generic standards EN 61000-6-2 and EN
61000-6-4 (for EMC directive) and with the standard EN 60255-6 (for Low Voltage Di-
rective) by Siemens AG.
The device is designed and manufactured for application in industrial environment.
The product conforms with the international standards of IEC 60255 and the German
standard VDE 0435.

Preface
iv 7SS52 V4 Manual
C53000-G1176-C182-1
Additional support For any questions concerning your SIPROTEC system, please contact your Siemens
representative.
Training courses Individual course offers may be found in our Training Catalog, or questions can be di-
rected to our training center in Nuremberg.
Instructions and
Warnings
The warnings and notes contained in this manual serve for your own safety and for an
appropriate lifetime of the device. Please observe them!
The following terms and definitions are used:
DANGER
indicates that death, severe personal injury or substantial property damage will result
if proper precautions are not taken.
Warning
indicates that death, severe personal injury or substantial property damage can result
if proper precautions are not taken.
Caution
indicates that minor personal injury or property damage can result if proper precau-
tions are not taken. This is especially valid for damage on or in the device itself and
consequential damage thereof.
Note
indicates information about the device or respective part of the instruction manual
which is essential to highlight.
Warning!
Hazardous voltages are present in this electrical equipment during operation. Non–
observance of the safety rules can result in severe personal injury or property dam-
age.
Only qualified personnel shall work on and around this equipment after becoming thor-
oughly familiar with all warnings and safety notices of this manual as well as with the
applicable safety regulations.
The successful and safe operation of this device is dependent on proper handling, in-
stallation, operation, and maintenance by qualified personnel under observance of all
warnings and hints contained in this manual.
In particular the general erection and safety regulations (e.g. IEC, DIN, VDE, EN or
other national and international standards) regarding the correct use of hoisting gear
must be observed. Non–observance can result in death, personal injury or substantial
property damage.

Preface
v
7SS52 V4 Manual
C53000-G1176-C182-1
QUALIFIED PERSONNEL
For the purpose of this instruction manual and product labels, a qualified person is one
who is familiar with the installation, construction and operation of the equipment and
the hazards involved. In addition, he or she has the following qualifications:
•Is trained and authorized to energize, de-energize, clear, ground and tag circuits
and equipment in accordance with established safety practices.
•Is trained in the proper care and use of protective equipment in accordance with es-
tablished safety practices.
•Is trained in rendering first aid.
Typographic
and symbol
conventions
The following text formats are used when literal information from the device or to the
device appear in the text flow:
Parameter names, i.e. designators of configuration or function parameters, which
may appear word-for-word in the display of the device or on the screen of a personal
computer (with DIGSI), are marked in bold letters of a monospace type style.
Parameter options, i.e. possible settings of text parameters, which may appear
word-for-word in the display of the device or on the screen of a personal computer
(with DIGSI), are written in italic style, additionally. This applies also for options in
menus.
“Annunciations”, i.e. designators for information, which may be output by the relay
or required from other devices or from the switch gear, are marked in a monospace
type style in quotes.
Deviations may be permitted in drawings when the type of designator can be obviously
derived from the illustration.
The following symbols are used in drawings:
Device-internal logical input signal
Device-internal logical output signal
Internal input signal of an analog quantity
External binary input signal with number (binary input,
input indication)
External binary output signal with number (device indi-
cation)
Example of a parameter switch designated with the
address and the possible settings

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Besides these, graphical symbols are used according to IEC 60 617–12 and
IEC 60 617–13 or symbols derived from these standards. The most frequent symbols
are the following:
Input signal of an analogue quantity
OR-combination of input values
AND-combination of input values
Exclusive–OR gate: output is active, if only one of the
inputs is active
“>2“ at least two inputs are active
Coincidence: output is active if both inputs are active
or inactive at the same time
Dynamic input signals (edge–triggered) above with
positive, below with negative edge
Formation of one analogue output signal from a
number of analogue input signals
Limit value stage with parameter address and param-
eter name
Timer (pickup delay T adjustable) with parameter
address and parameter name
Timer (dropout delay T, non-adjustable)
Edge-controlled time stage with effective time T
Static memory (RS-flipflop) with setting input (S),
resetting input (R), output (Q) and inverted output (Q)
Circuit breaker (open and closed)
Isolator (open and closed)

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1 Introduction.......................................................................................................................................... 1
1.1 Overall Operation ................................................................................................................... 2
1.2 Applications ............................................................................................................................ 4
1.3 Features ................................................................................................................................. 5
2 Design and Connection System....................................................................................................... 13
2.0 General................................................................................................................................. 14
2.1 Central Unit .......................................................................................................................... 15
2.1.1 Front View ............................................................................................................................ 15
2.1.2 Modules and Submodules.................................................................................................... 16
2.1.3 Design .................................................................................................................................. 17
2.1.3.1 Subrack ES902 C (SIPAC)................................................................................................... 17
2.1.3.2 Wall-mounted housing.......................................................................................................... 17
2.1.3.3 8MF Cubicle ......................................................................................................................... 17
2.2 Bay Unit................................................................................................................................ 18
2.2.1 Front View ............................................................................................................................ 18
2.2.2 Modules and Submodules.................................................................................................... 19
2.2.3 Design .................................................................................................................................. 21
2.2.3.1 Panel Surface Mounting ....................................................................................................... 21
2.2.3.2 Panel Flush Mounting or Cubicle Mounting.......................................................................... 21
2.3 Connection Method .............................................................................................................. 22
2.3.1 Location of Device Connections ........................................................................................... 22
2.3.2 Device Connections.............................................................................................................. 25
2.3.2.1 Screw-Type Terminals.......................................................................................................... 26
2.3.2.2 Double Leaf-Spring-Crimp Contacts..................................................................................... 26
2.3.2.3 D-SUB Female Connectors ..................................................................................................27
2.3.2.4 Fiber-Optic Cable Connections ............................................................................................27
2.3.2.5 EN100 module Ethernet (IEC 61850)................................................................................... 28
3 Getting Started................................................................................................................................... 29
3.1 Unpacking and Repacking.................................................................................................... 30
3.2 Checking the Rated Data ..................................................................................................... 30
3.3 Matching the Control Voltage for the Binary Inputs and
Inserting the Buffer Battery................................................................................................... 31
3.4 Electrical Checks.................................................................................................................. 38
3.5 Setting up the Communication between the Central Unit
and the Bay Unit................................................................................................................... 39

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3.6 Operation of SIPROTEC Devices from the Operator Panel ................................................. 40
3.6.1 User Interface ....................................................................................................................... 40
3.6.2 Navigating the Operating Tree of the Display....................................................................... 40
3.6.3 Setting Addresses in the Bay Unit ........................................................................................ 41
3.6.4 Adjusting the Display Contrast.............................................................................................. 42
3.7 Storage ................................................................................................................................. 44
4 Configuration ..................................................................................................................................... 45
4.1 Creating a Project................................................................................................................. 46
4.2 Inserting Central Unit / Bay Units.......................................................................................... 47
4.3 Plant Configuration ............................................................................................................... 49
4.3.1 How to Proceed .................................................................................................................... 49
4.3.2 Starting the Plant Configuration............................................................................................ 50
4.3.3 Drawing Busbars ................................................................................................................. 52
4.3.4 Defining Bays........................................................................................................................ 54
4.3.5 Inserting Dynamic Elements.................................................................................................55
4.3.6 Connecting Dynamic Elements to the Busbars .................................................................... 57
4.3.6.1 Inserting Lines ...................................................................................................................... 57
4.3.6.2 Inserting a Connection.......................................................................................................... 58
4.3.7 Inserting Static Text.............................................................................................................. 59
4.3.8 Creating and Inserting Typicals. ...........................................................................................59
4.3.9 Saving the Substation Chart................................................................................................. 60
4.4 Assigning Bay Units.............................................................................................................. 61
4.5 Marshalling ........................................................................................................................... 63
4.5.1 Marshalling Information Items of the Central Unit................................................................. 63
4.5.1.1 Allocable Information ............................................................................................................ 63
4.5.1.2 Marshalling ........................................................................................................................... 64
4.5.2 Marshalling Bay Unit Information.......................................................................................... 66
4.5.2.1 Allocable Information ............................................................................................................ 66
4.5.2.2 Marshalling ........................................................................................................................... 67
4.6 Settings................................................................................................................................. 70
4.6.1 Serial Ports ........................................................................................................................... 71
4.6.2 Date/Clock Management......................................................................................................75
4.7 Concluding the Configuration ............................................................................................... 79
4.8 Configuration Notes.............................................................................................................. 81

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5 Functions............................................................................................................................................ 91
5.1 Busbar Protection ................................................................................................................. 92
5.1.1 Mode of operation ................................................................................................................ 92
5.1.1.1 Basic Principle...................................................................................................................... 92
5.1.1.2 Algorithm with Instantaneous Values ................................................................................... 94
5.1.1.3 Separate Evaluation of Half-Cycles...................................................................................... 96
5.1.1.4 Evaluation of the Initial Values ............................................................................................. 99
5.1.1.5 Algorithm with Filtered Values............................................................................................ 100
5.1.1.6 Summary of the Measuring Method ................................................................................... 100
5.1.2 Isolator Replica................................................................................................................... 101
5.1.3 Bus Coupler Variants.......................................................................................................... 103
5.1.3.1 Bus Couplers with One Current Transformer ..................................................................... 103
5.1.3.2 Bus Couplers with Two Current Transformers ................................................................... 103
5.1.3.3 Bus Couplers without Circuit Breaker................................................................................. 104
5.1.3.4 Bus Couplers with more than 5 Isolators............................................................................ 104
5.1.3.5 Combi-Coupler ................................................................................................................... 104
5.1.3.6 Transfer Busbars................................................................................................................ 105
5.1.3.7 Transfer Busbar Protection With Inside Transformers ....................................................... 107
5.1.4 Setting Notes...................................................................................................................... 107
5.1.5 Settings for the Central Unit ............................................................................................... 110
5.2 Check Zone ........................................................................................................................ 111
5.2.1 Mode of operation .............................................................................................................. 111
5.2.2 Setting Notes...................................................................................................................... 112
5.2.3 Settings for the Central Unit ............................................................................................... 112
5.3 Circuit Breaker Failure Protection....................................................................................... 113
5.3.1 Characteristics for the Circuit Breaker Failure Protection................................................... 113
5.3.2 Setting Notes...................................................................................................................... 114
5.3.3 Settings for the Central Unit ............................................................................................... 115
5.3.4 List of Information from the Central Unit............................................................................. 115
5.3.5 Bay-Specific Functions (BU)............................................................................................... 116
5.3.5.1 Triggering and Releasing the Breaker Failure Protection................................................... 116
5.3.5.2 Circuit Breaker Failure Protection during a Feeder Short-Circuit ....................................... 118
5.3.5.3 Circuit Breaker Failure Protection for Busbar Faults .......................................................... 124
5.3.5.4 Failure of the Bus Coupler Circuit Breaker ......................................................................... 125
5.3.5.5 Circuit Breaker Not Ready.................................................................................................. 125
5.3.6 Setting Notes...................................................................................................................... 126
5.3.7 Settings for the Central Unit ............................................................................................... 129
5.3.8 List of Information from the Central Unit............................................................................. 130
5.3.9 List of Information from the Bay Unit .................................................................................. 131

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5.4 End Fault Protection ........................................................................................................... 132
5.4.1 End Fault Protection in the Feeder ..................................................................................... 132
5.4.2 Protection in the ”Dead Zone” of the Bus Coupler.............................................................. 134
5.4.2.1 Circuit Breaker Closed........................................................................................................ 134
5.4.2.2 Circuit Breaker Open .......................................................................................................... 135
5.4.2.3 CLOSE Command of the Bus Coupler Circuit Breaker ...................................................... 136
5.4.3 Setting Notes ...................................................................................................................... 137
5.4.4 Settings for the Central Unit................................................................................................ 137
5.4.5 List of Information from the Central Unit............................................................................. 138
5.4.6 List of Information from the Bay Unit .................................................................................. 138
5.5 Supervisory Functions .......................................................................................................139
5.5.1 Functional Description ........................................................................................................ 139
5.5.1.1 Zone-Selective Blocking ..................................................................................................... 139
5.5.1.2 Auxiliary and Reference Voltages....................................................................................... 141
5.5.1.3 Measured Value Supervision.............................................................................................. 141
5.5.1.4 Output Trip Supervision ...................................................................................................... 142
5.5.1.5 Battery Monitoring............................................................................................................... 142
5.5.1.6 Supervision in Maintenance Mode...................................................................................... 142
5.5.1.7 Cyclic Test .......................................................................................................................... 143
5.5.1.8 Supervision of External Current Transformer Circuits ........................................................ 143
5.5.1.9 Isolator Status Supervision................................................................................................. 145
5.5.1.10 Supervisory of Circuit Breaker............................................................................................ 148
5.5.1.11 Overview of the Supervisory Functions .............................................................................. 149
5.5.2 Setting Notes ...................................................................................................................... 152
5.5.3 Settings for the Central Unit................................................................................................ 155
5.5.4 List of Information from the Central Unit............................................................................. 156
5.5.5 List of Information from the Bay Unit .................................................................................. 157
5.6 Oscillographic Fault Recording........................................................................................... 158
5.6.1 Mode of operation............................................................................................................... 158
5.6.2 Setting Notes ...................................................................................................................... 159
5.6.3 Settings for the Central Unit................................................................................................ 160
5.6.4 Settings of the Bay Unit ...................................................................................................... 160
5.6.5 List of Information from the Central Unit............................................................................. 160
5.7 Device................................................................................................................................. 161
5.7.1 Mode of operation............................................................................................................... 161
5.7.2 Annunciations ..................................................................................................................... 161
5.7.3 List of Information from the Central Unit............................................................................. 163
5.8 Power System Data ............................................................................................................164
5.8.1 Mode of operation............................................................................................................... 164
5.8.2 Setting Notes ...................................................................................................................... 164
5.8.3 Settings for the Central Unit................................................................................................ 164
5.8.4 Settings of the Bay Unit ...................................................................................................... 164

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5.9 Protection General ............................................................................................................. 165
5.9.1 Current-Controlled TRIP Reset .......................................................................................... 165
5.9.2 Local Control of the Bay Unit..............................................................................................165
5.9.3 Operating States "Bay Out of Service", "Maintenance Mode"............................................ 166
5.9.4 Overcurrent-Controlled TRIP command ............................................................................. 167
5.9.5 Feeder-Selective Trip Release ........................................................................................... 168
5.9.6 Testing the Tripping Circuits and the Circuit Breakers ....................................................... 168
5.9.7 Busbar Tripping via an External Signal .............................................................................. 169
5.9.8 Setting Notes...................................................................................................................... 169
5.9.9 Settings for the Central Unit ............................................................................................... 172
5.9.10 List of Information from the Central Unit............................................................................. 173
5.9.11 Settings for the Bay Unit..................................................................................................... 173
5.9.12 List of Information from the Bay Unit .................................................................................. 173
5.10 Bay Unit.............................................................................................................................. 174
5.10.1 Functional Description ........................................................................................................ 174
5.10.2 Setting Notes...................................................................................................................... 174
5.11 Integrated Operation of the Bay Unit .................................................................................. 175
5.11.1 Functional Description ........................................................................................................ 175
5.11.2 Setting Notes...................................................................................................................... 175
5.11.3 Settings of the Bay Unit...................................................................................................... 176
5.12 PC Port of the Bay Unit ...................................................................................................... 177
5.12.1 Functional Description ........................................................................................................ 177
5.12.2 Setting Notes...................................................................................................................... 177
5.12.3 Settings of the Bay Unit...................................................................................................... 178
5.13 Fault Recording in the Bay Unit (”Local Fault Recording”) ................................................. 179
5.13.1 Functional Description ........................................................................................................ 179
5.13.2 Setting Notes...................................................................................................................... 179
5.13.3 Settings of the Bay Unit...................................................................................................... 180
5.14 Scope of Protective Functions in the Bay Unit ................................................................... 181
5.14.1 Functional Description ........................................................................................................ 181
5.14.2 Setting Notes...................................................................................................................... 181
5.14.3 Settings of the Central Unit................................................................................................. 182
5.14.4 Settings of the Bay Unit...................................................................................................... 182
5.15 Power System Data of the Bay Unit ................................................................................... 183
5.15.1 Functional Description ........................................................................................................ 183
5.15.2 Setting Notes...................................................................................................................... 183
5.15.3 Settings of the Central Unit................................................................................................. 184
5.15.4 Settings of the Bay Unit...................................................................................................... 184

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5.16 Overcurrent Protection in the Bay Unit ............................................................................... 185
5.16.1 Functional Description ........................................................................................................ 185
5.16.2 Setting Notes ...................................................................................................................... 187
5.16.3 Settings of the Bay Unit ...................................................................................................... 191
5.16.4 List of Information from the Bay Unit .................................................................................. 193
5.17 User-Defined Annunciations............................................................................................... 194
5.17.1 Functional Description ........................................................................................................ 194
5.17.2 Setting Notes ...................................................................................................................... 195
5.17.3 Settings of the Bay Unit ...................................................................................................... 195
5.17.4 List of Information from the Bay Unit .................................................................................. 196
5.18 Backup Breaker Failure Protection in the Bay Unit............................................................. 197
5.18.1 Functional Description ........................................................................................................ 197
5.18.2 Setting Notes ...................................................................................................................... 200
5.18.3 Settings of the Central Unit................................................................................................. 200
5.18.4 List of Information from the Central Unit............................................................................. 201
5.18.5 Settings of the Bay Unit ...................................................................................................... 201
5.18.6 List of Information from the Bay Unit .................................................................................. 202
6 Control During Operation................................................................................................................ 203
6.1 Overview............................................................................................................................. 204
6.2 Reading Out Information..................................................................................................... 206
6.2.1 Annunciations ..................................................................................................................... 206
6.2.1.1 Operational Annunciations.................................................................................................. 208
6.2.1.2 Fault events ........................................................................................................................ 209
6.2.1.3 Alarm List............................................................................................................................ 211
6.2.1.4 General Interrogation.......................................................................................................... 211
6.2.1.5 Spontaneous Annunciation.................................................................................................212
6.2.1.6 Statistics ............................................................................................................................. 212
6.2.2 Reading Out Measured Values........................................................................................... 213
6.2.3 Reading Out Fault Data ...................................................................................................... 215
6.3 Controlling Device Functions .............................................................................................. 218
6.3.1 Creating an Oscillographic Record ..................................................................................... 218
6.3.2 Blocking .............................................................................................................................. 219
6.3.2.1 Blocking the TRIP Command ............................................................................................. 219
6.3.2.2 Blocking the Breaker Failure Protection ............................................................................. 222
6.3.2.3 Blocking of Individual Busbar Sections............................................................................... 224
6.3.3 Saving and Deleting Annunciations.................................................................................... 225
6.3.3.1 Saving Annunciations ......................................................................................................... 225
6.3.3.2 Deleting Annunciations ....................................................................................................... 226
6.3.4 Circuit Breaker Test ............................................................................................................ 227
6.3.5 Reset Blocking.................................................................................................................... 229
6.3.5.1 Reset Blocking of Differential Current Supervision............................................................. 229
6.3.5.2 Reset Blocking of Isolator Fault .......................................................................................... 230
6.3.6 Trigger Initial Start and Restart........................................................................................... 230
6.3.7 Read and Set Date / Time.................................................................................................. 231

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6.4 Feeder Shutdown and Commissioning............................................................................... 236
6.5 Maintenance Mode.............................................................................................................239
6.6 Plant Visualization .............................................................................................................. 241
7 Installation and Commissioning .................................................................................................... 245
7.1 Installation and Commissioning.......................................................................................... 246
7.1.1 Central Unit ........................................................................................................................ 246
7.1.2 Bay Unit.............................................................................................................................. 247
7.1.3 General Information on the 2-Bay Bus Coupler.................................................................. 248
7.1.3.1 General............................................................................................................................... 248
7.1.3.2 2-Bay Bus Coupler With 2 Current Transformers............................................................... 249
7.1.3.3 2-Bay Bus Coupler With one Current Transformer............................................................. 249
7.1.3.4 Connection ......................................................................................................................... 249
7.2 Checking the Connections.................................................................................................. 251
7.3 Commissioning .................................................................................................................. 252
7.3.1 How to Proceed.................................................................................................................. 253
7.3.2 Web Monitor ....................................................................................................................... 254
7.3.2.1 General............................................................................................................................... 254
7.3.2.2 Functions............................................................................................................................ 255
7.3.2.3 Operating Modes................................................................................................................ 260
7.3.3 Checking the Switching States of the binary Inputs/Outputs.............................................. 262
7.3.3.1 Central Unit ........................................................................................................................ 262
7.3.3.2 Bay Unit.............................................................................................................................. 264
7.3.4 Testing the System Port ..................................................................................................... 266
7.3.5 Control of the Isolator Replica ............................................................................................268
7.3.6 Switching the Test Mode and the Transmission Block On and OFF. ................................. 269
7.4 Checks With Secondary Values ......................................................................................... 270
7.4.1 General............................................................................................................................... 270
7.4.2 Trip Characteristic of the Busbar Protection....................................................................... 271
7.4.2.1 busbar-selective Protection ................................................................................................ 271
7.4.2.2 Check Zone ........................................................................................................................ 273
7.4.3 Differential Current Monitoring............................................................................................275
7.4.3.1 busbar-selective Protection ................................................................................................ 275
7.4.3.2 Check Zone ........................................................................................................................ 276
7.4.3.3 Time Delay ......................................................................................................................... 276
7.4.4 Overcurrent Threshold Tripping.......................................................................................... 277
7.4.5 Breaker Failure Protection.................................................................................................. 277
7.4.5.1 Trip Characteristic for Operating Mode “Unbalancing” ....................................................... 277
7.4.5.2 Delay Time at Operating Mode “Unbalancing” and “I>Query” ............................................ 278
7.4.6 Finishing the Tests with Secondary Values........................................................................ 278
7.5 Checks With Primary Values .............................................................................................. 279
7.5.1 Transformer Polarity ........................................................................................................... 279
7.6 Final Check of the Protection ............................................................................................. 280

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8 Maintenance and Repair.................................................................................................................. 281
8.1 Maintenance ..................................................................................................................... 282
8.2 Fault Analysis ..................................................................................................................... 284
8.2.1 Evaluation of Operational Events ....................................................................................... 284
8.2.2 Checking the Auxiliary Voltage Supply ............................................................................... 285
8.2.3 Checking the LEDs on the Modules ................................................................................... 285
8.2.4 Analysis of Internal Communication Failures...................................................................... 287
8.3 Troubleshooting.................................................................................................................. 290
8.4 Repair ................................................................................................................................. 293
8.4.1 Replacing the Buffer Battery...............................................................................................294
8.4.2 Replacing the Fine-Wire Fuse ............................................................................................ 297
8.4.3 Startup with a Defective Bay Unit / Defective Fiber-Optic Cable ........................................ 300
9 Technical Data.................................................................................................................................. 301
9.1 General Data ...................................................................................................................... 302
9.2 General Device Data ..........................................................................................................303
9.2.1 Analog Inputs and Outputs ................................................................................................. 303
9.2.2 Rated Auxiliary Voltage ...................................................................................................... 303
9.2.3 Binary Inputs....................................................................................................................... 304
9.2.4 Alarm Contacts ................................................................................................................... 304
9.2.5 Trip Contacts ...................................................................................................................... 305
9.2.6 Light Emitting Diodes.......................................................................................................... 305
9.2.7 Operation, Displays ............................................................................................................ 305
9.2.8 Serial Ports ......................................................................................................................... 306
9.2.9 Busbar Protection ............................................................................................................... 307
9.2.10 Circuit Breaker Failure Protection....................................................................................... 308
9.2.11 Overcurrent Protection in the Bay Unit ............................................................................... 309
9.2.12 Auxiliary Functions.............................................................................................................. 311
9.2.13 User-Configurable Functions (CFC) ................................................................................... 312
9.2.14 Electrical Tests ................................................................................................................... 313
9.2.15 Mechanical Tests................................................................................................................ 315
9.2.16 Climatic Stress Tests.......................................................................................................... 316
9.2.17 Service Conditions.............................................................................................................. 317
9.2.18 Design Versions.................................................................................................................. 317
9.2.19 MCBs for Device 7SS52x ................................................................................................... 318
9.3 Dimensions......................................................................................................................... 319
9.3.1 Central Unit......................................................................................................................... 319
9.3.2 Bay Unit .............................................................................................................................. 322

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A Appendix .......................................................................................................................................... 327
A.1 Data for Selection and Ordering ......................................................................................... 328
A.1.1 Central Unit ........................................................................................................................ 328
A.1.2 Bay Units ............................................................................................................................ 329
A.1.3 Accessories ........................................................................................................................ 330
A.2 Basis for Selection of the Stabilization Factor k ................................................................. 333
A.3 Connection Diagrams......................................................................................................... 334
A.4 Settings −Central Unit........................................................................................................ 340
A.4.1 Settings of the ZPS Modules .............................................................................................. 340
A.4.2 Settings of the EAZ Module................................................................................................ 342
A.4.3 Jumper Settings of the D-CPU Module .............................................................................. 344
A.5 Jumper Settings −Bay Unit ................................................................................................ 346
A.5.1 Settings of the PFE Module................................................................................................ 346
A.5.2 Settings of the SVW Module............................................................................................... 347
A.5.3 Settings of the SAF Module................................................................................................ 348
A.5.4 Settings of the AFE Module................................................................................................ 349
A.5.5 Settings of the EFE Module................................................................................................ 350
A.5.6 Settings of the EFE_10 Module.......................................................................................... 352
A.6 Protocol-Dependent Functions........................................................................................... 354
A.7 Parameter Listing - Central Unit ......................................................................................... 355
A.8 Parameter Listing - Bay Unit............................................................................................... 357
A.9 List of information - Central Unit......................................................................................... 362
A.10 List of Information - Bay Unit ..............................................................................................372
A.11 Group Alarms - Central Unit ............................................................................................... 378
A.12 Group Alarms - Bay Unit.....................................................................................................382
A.13 Measured Value List - Central Unit..................................................................................... 383
A.14 Measured Value List - Bay Unit .......................................................................................... 384
A.15 Marshalling - Central Unit ................................................................................................... 385
A.16 Marshalling - Bay Unit 7SS523........................................................................................... 388
A.17 Marshalling - Bay Unit 7SS525........................................................................................... 391
A.18 Navigation Tree - Central Unit ............................................................................................ 393
A.19 Navigation Tree of the Bay Unit.......................................................................................... 403
A.20 Abbreviations...................................................................................................................... 404
A.21 References ......................................................................................................................... 405

xvi 7SS52 V4 Manual
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17SS52 V4 Manual
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Introduction 1
This chapter introduces the SIPROTEC 7SS52 V4 distributed busbar and breaker fail-
ure protection. An overview of the device is presented in its application, characteris-
tics, and scope of functions.
1.1 Overall Operation 2
1.2 Applications 4
1.3 Features 5

Introduction
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1.1 Overall Operation
The SIPROTEC 7SS52 V4 distributed busbar and breaker failure protection consists
of compact bay units which are connected to the central unit by fiber-optic cables. Fig-
ure 1-1, page 3 shows the basic structure of the protection system.
All tasks from acquisition of the measured values up to the commands to the circuit
breakers are exclusively processed in a digital manner.
In the bay units the feeder or coupler currents are measured time-synchronized, digi-
talized, preprocessed and transmitted to the central unit via the fast serial port. The
input nominal current can be 1 or 5 A depending on the main current transformer de-
sign. A full galvanic and low-capacitive isolation of the measuring inputs is provided
by transducers. Suppression of disturbances is achieved by filters which are optimized
for the measured value processing with regard to bandwidth and processing speed.
Bay units The bay units can be parameterized and operated either directly or from the central
unit. Chapter 6.1, page 204 summarizes the operator options during operation.
The bay units capture the isolator positions and bay-related binary signals, process
functions of the breaker failure protection and fulfil auto diagnosis tasks.
Heavy-duty command relays take the protection system's trip commands directly to
the circuit breakers. Marshallable alarm relays and indicators (LEDs, LC display,
DIGSI communication software) allow event indication. In addition operational meas-
ured values are displayed.
For the marshalling of isolator positions, command relays, alarm relays and allocata-
ble binary inputs the DIGSI communication software is used.
Optionally, the bay units can be equipped with a backup protection function (definite-
time, inverse-time) including breaker failure protection.
Central unit The central unit reads in time-synchronized measured currents from the connected
bay units and processes them together with binary information from the protection
functions (differential protection, breaker failure protection). The central unit transmits
the results of the calculations cyclically to the bay units, which perform logical combi-
nations of the results.
Freely marshallable alarm relays and LED displays are provided for signalling. They
are marshalled with the DIGSI communication software.
The central unit manages all configuration and setting data for the busbar and breaker
failure protection functions. Communication is possible via the serial port by means of
a PC utilizing a current version of the DIGSI communication software. With DIGSI V4.6
the central unit - but not the bay unit - can also be operated via IEC 61850 with the
optional EN100 module. Indications, parameters and measured values are visualized
in the display or in DIGSI. In addition the program can read out fault data from the pro-
tection device and analyze it.
The central unit and bay units contain power supply modules for a reliable power sup-
ply on different voltage ranges.

Overall Operation
3
7SS52 V4 Manual
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Figure 1-1 General view of the configuration of the protection system
SBK: Protection processing SC: Serial coupling
DPR: Dual port RAM PS: Power supply
I/O CU: Input/output central unit ZPS: Central processor protection
SBK: Bus master

Introduction
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1.2 Applications
Application The SIPROTEC 7SS52 V4 distributed busbar and breaker failure protection is a se-
lective, reliable and fast protection for busbar short-circuits and circuit-breaker failures
in medium-voltage, high-voltage and extra high-voltage switching stations. It is suita-
ble for almost all busbar configurations.
The busbar protection uses a phase-selective measuring principle.
The protection system consists of a central unit (CU) and up to 48 bay units (BU) con-
nected by fiber-optic (FO) cables. The latter can be located in the vicinity of the bays
(distributed) but also together with the CU in cubicles (centralized).
Use and scope of
functions
The protection can be used with all types of switchgear with either conventional or lin-
earized CTs.
The modular design facilitates extensions or modifications of the protection system in
conformity with the switchgear design.
The 7SS52 V4 is designed for 12 selective bus zones and 12 bus coupler (auxiliary
bus) sections. These are sections which serve exclusively for coupling of the bus
zones. They do not have any feeders. The busbar configuration can include up to 24
sectionalizing isolators and 16 bus couplers with one bay unit or 8 bus couplers with
two bay units.
By virtue of the universal isolator replica, the SIPROTEC 7SS52 V4 distributed busbar
and breaker failure protection can be matched with different busbar configurations in
the design phase.
Compensation of different current transformer ratios is achieved by parameter setting.
Interposing current transformers are thus no more required.
A busbar short-circuit is detected by evaluating the differential current and the stabi-
lizing current. Appropriate measures ensure correct performance even for extreme CT
saturation (requested current transmission time ≥2 ms for stability in the case of ex-
ternal faults and ≥3 ms for tripping).
The integrated circuit breaker failure protection (CBF) can be operated in five modes,
selectable per bay (see Chapter 5.3.5.2, page 118):
•I>query (1-stage CBF)
•TRIP repetition with overcurrent detection I>(2-stage CBF)
•Unbalancing (1-stage CBF)
•TRIP repetition with following unbalancing (2-stage CBF)
•Single-pole or three-pole start by external CBF and tripping via the isolator replica
In addition, the integrated circuit breaker failure protection provides two operating
modes that can be set in parallel to the other five modes (see Chapter 5.3.5.2, page
118):
•Low-current operating mode without/with TRIP repetition
•Pulse mode