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7SG12 DAD-N Contents  

 

The copyright and other intellectual property rights in this document, and in any model or article produced from it 
(and including any registered or unregistered design rights) are the property of Siemens Protection Devices 
Limited. No part of this document shall be reproduced or modified or stored in another form, in any data retrieval 
system, without the permission of Siemens Protection Devices Limited, nor shall any model or article be 
reproduced from this document unless Siemens Protection Devices Limited consent.  
 
While the information and guidance given in this document is believed to be correct, no liability shall be accepted 
for any loss or damage caused by any error or omission, whether such error or omission is the result of 
negligence or any other cause. Any and all such liability is disclaimed. 
 
©2010 Siemens Protection Devices Limited 

 

Contents 
 
Technical Manual Chapters 

 

Description of Operation 

 
2 Performance 

Specification 

 
3 Relay 

Settings 

 
4 Communication 

Interface 

 
5 Applications 

Guide 

 
6 Installation 
 
7 Commissioning 
 
8 Maintenance 
 
9 Diagrams 

 
 
 

Summary of Contents for 7SG12 DAD-N

Page 1: ...Reyrolle Protection Devices 7SG12 DAD N Numerical High Impedance Relay with CT Supervision Answers for energy ...

Page 2: ......

Page 3: ...model or article be reproduced from this document unless Siemens Protection Devices Limited consent While the information and guidance given in this document is believed to be correct no liability shall be accepted for any loss or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemen...

Page 4: ...onsent While the information and guidance given in this document is believed to be correct no liability shall be accepted for any loss or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemens Protection Devices Limited 7SG12 DAD N Numerical High Impedance Relay with CT Supervision D...

Page 5: ... 3 2 IEC 60870 5 103 Time Synchronisation 7 4 3 3 Real Time Clock Time Synchronisation 7 4 4 Communications 7 4 5 Settings Groups 7 4 6 Password Feature 7 5 USER INTERFACE 8 5 1 Liquid Crystal Display 8 5 2 Back light Control 8 5 3 LED Indications 8 5 4 Keypad 8 5 5 Relay Identifier 8 5 6 Settings Mode 8 5 6 1 Settings Adjustment 8 5 6 2 Settings And Displays 9 5 7 Instruments Mode 10 5 7 1 Hidden...

Page 6: ...N A B C 1A 17 20 19 18 22 21 28 27 26 25 24 23 AN1 5A Ia Ib Ic R R R DAD N 101 High Impedence Numerical Differential CT 50 87 50 1 AN1C1 C3 87 50 2 1A 5A 1A 5A Figure 1 DAD N 101 Numerical High Impedance protection 2 Hardware Description 2 1 General The structure of the relay is based upon the Modular II hardware and software platform illustrated in Figure 2 where the required cards plug in from t...

Page 7: ... Fascia LED and or to any Output Relay contact This allows the Relay to act as panel indication for alarms and scheme status without having to use additional external flagging elements 2 4 Output Relays The relay may be fitted with 13 output relays all of which are capable of handling circuit breaker tripping duty All relays are fully user configurable and can be programmed to operate from any or ...

Page 8: ... in Figure 4 High Impedance Differential Schematic The protection consists of a DTL over current element 87 50 per phase which is used for tripping Transient stability under through fault conditions is a problem with many forms of differential protection due to variations in CT magnetising characteristics When saturation is approached the current transformer output waveforms become increasingly di...

Page 9: ...lowing selection Five records of one second duration Two records of two seconds duration One record of five seconds duration The waveform recorder will be triggered automatically when any protection element operates It can also be triggered by any of the following means Via the Trigger Storage status input signal Via the IEC870 5 103 communications interface The waveform recorder has a settable pr...

Page 10: ...w transfer of the following Relay Settings Waveform Records Event Records Fault Data Records Instrument and meters Control Functions Communications operation is described in detail in Section 4 of this manual For information about all aspects of the communications protocol used in the Modular II range of relays see Section 4 4 5 Settings Groups Depending upon the relay model then up to eight alter...

Page 11: ...nated to indicate that DC volts have been applied to the relay and that the relay is operating correctly If the internal relay watchdog detects a protection relay unhealthy condition then this LED will continuously flash Programmable Red LED An LED MENU is provided to map any relay output or any status input to any LED 5 4 Keypad Five pushbuttons are used to control the functions of the relay They...

Page 12: ...ay which are the Settings Mode Instruments Mode and the Fault Data Mode When the relay is first energised the user is presented with the following message SETTINGS DEFAULTED PRESS ENTER This shows that the relay has been set with the standard factory default settings If this message is displayed ENTER must be pressed to acknowledge this initial condition the display will then indicate the relay id...

Page 13: ... Currents 0 00 0 00 0 00 xIn Differential Nominal currents MISC METERS press down Start of miscellaneous meters Status Inputs 1 16 Displays the state of DC status inputs 1 to 16 1 Status Inputs 17 27 Displays the state of DC status inputs 17 to 27 1 Output Relays 1 16 Displays the state of output relays 1 to 16 2 Output Relays 17 29 Displays the state of output relays 17 to 29 2 Time Date 13 08 20...

Page 14: ...ed Time Date D 01 01 2002 01 31 39 If no keys have been pressed for a pre determined time the relay will jump to the default instrument display regardless of where the menu has been left by the user It will then scroll through each of the selected default instruments and remain on each for approximately 5 seconds The Default Screens Timer that sets the time to elapse before the relay goes into the...

Page 15: ...7SG12 DAD N Description of Operation 6 Diagrams Figure 2 DAD N in E8 case with front panel open Figure 3 DAD N Rear View 2010 Siemens Protection Devices Limited Chapter 1 Page 12 of 14 ...

Page 16: ...7SG12 DAD N Description of Operation PHASE A R E S 87 50 1 87 50 2 CT 50 Figure 4 High Impedance Differential Schematic 2010 Siemens Protection Devices Limited Chapter 1 Page 13 of 14 ...

Page 17: ...QUIRED TO NAVIGATE THE MENU SYSTEM READ UP READ DOWN TEST RESET ENTER CANCEL ESCAPE MISC METERS PRESS DOWN COMMUNICATIONS MENU to view LED MENU to view Output Relays 1 5 1 _ _ _ _ Time Date 16 07 2001 11 49 17 Status Inputs 1 3 _ _ _ CANCEL ESCAPE OUTPUT RELAY MENU to view DATA STORAGE MENU to view TRIP CCT SUPERVISION MENU to view STATUS INPUT MENU to view REYLOGIC ELEMENTS MENU to view CT SUPERV...

Page 18: ...s or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemens Protection Devices Limited 7SG12 DAD N Numerical High Impedance Relay with CT Supervision Document Release History This document is issue 2010 02 The list of revisions up to and including this issue is Pre release 2010 02 Do...

Page 19: ...gizing Quantity 4 4 3 A C Current Inputs 5 4 4 Output Contacts 5 4 5 Status inputs 5 4 6 Indication 6 4 7 Settings And Configuration 6 4 8 Recording 6 4 9 Communications 6 4 10 IRIG B Time Synchronisation 7 5 PROTECTION ELEMENTS 7 5 1 Common Performance 7 5 2 87 50 1 87 50 2 Differential 7 5 3 CT 50 CT Supervision 7 5 4 Trip Circuit Supervision 7 2010 Siemens Protection Devices Limited Chapter 2 P...

Page 20: ...uracy Influencing Factors Temperature Ambient range 10 C to 55 C Variation over range 5 Frequency Range 50Hz Model Range 60Hz Model 47Hz to 52Hz 57Hz to 62Hz Setting variation 5 Operating time variation 5 4 Modular II Specification 4 1 Environmental Withstand Temperature IEC 60068 2 1 2 Operating range 10 C to 55 C Storage range 25 C to 70 C Humidity IEC 60068 2 3 Operational test 56 days at 40 C ...

Page 21: ...soidal IEC 60255 21 1 Class 1 Variation Vibration response 0 5gn 5 Vibration endurance 1 0gn 5 Shock and Bump IEC 60255 21 2 Class 1 Variation Shock response 5 gn 11ms 5 Shock withstand 15 gn 11ms 5 Bump test 10 gn 16ms 5 Seismic IEC 60255 21 3 Class 1 Variation Seismic Response 1gn 5 Mechanical Classification Durability In excess of 106 operations 4 2 Auxiliary Energizing Quantity DC Power Supply...

Page 22: ...act rating to IEC 60255 0 2 Carry continuously 5A ac or dc Make and Carry limit L R 40ms and V 300 volts for 0 5 sec 20A ac or dc for 0 2 sec 30A ac or dc Break limit 5A or 300 volts Ac resistive 1250VA Ac inductive 250VA PF 0 4 Dc resistive 75W Dc inductive 30W L R 40 ms 50W L R 10 ms Minimum number of operations 1000 at maximum load Minimum recommended load 0 5W limits 10mA or 5V 4 5 Status inpu...

Page 23: ...mory Configuration changes may be achieved locally via the front serial port with a Windows based toolbox support package Configuration changes and software upgrades are stored in Flash EPROM memory 4 8 Recording Up to 5 fault records may be stored within the relay Fault records are accessible via the front panel showing the date and time of trips New faults automatically overwrite the oldest faul...

Page 24: ...Differential Phase segregated High impedance Overall Differential scheme using external stabilizing resistors Function is insensitive to third harmonic currents Pickup 5 of setting or 0 01 In whichever is the greater Reset 95 of Is Repeatability 2 Transient Overreach 5 Operate Time 2 x Setting 4 x Setting Operate Time 1 cycle 1 cycle Time Delay 1 or 5ms whichever is the greater 5 3 CT 50 CT Superv...

Page 25: ...list of revisions up to and including this issue is Pre release Revision Date Change 2010 02 Document reformat due to rebrand R12 26 08 2005 Corrected TCS ranges and units R11 15 08 2005 Added 2 nd stage 87 50 2 Corrected TCS events numbers Minimum setting value reduced to 0 005xIn for 87 50 and 0 001xIn for CT 50 using 2513H10099 4xSEF analogue module Time steps now 5ms IEC Output relay drive add...

Page 26: ...Page 2 of 20 High Impedence Differential Protected Zone N A B C 1A 17 20 19 18 22 21 28 27 26 25 24 23 AN1 5A Ia Ib Ic R R R P1 P2 S1 S2 P1 P2 S1 S2 DAD N 101 CT50 87 50 1 AN1C1 C3 87 50 2 Model No Cat No Configuration No DAD N 101 DA1 101 2414H80001R15 Date 24 02 2010 12 55 00 ...

Page 27: ...ENU 5 1 6 STATUS INPUT MENU 5 1 7 STATUS INPUT TIMING MENU 6 1 8 REYLOGIC ELEMENT MENU 7 1 9 OUTPUT RELAY MENU 7 1 10 LED MENU 9 1 11 DATA STORAGE MENU 10 1 12 COMMUNICATIONS MENU 10 2 INSTRUMENTS 11 3 IEC 60870 5 103 COMMUNICATIONS INFORMATION 12 3 1 IEC 60870 5 103 Semantics in monitor direction 12 3 2 IEC 60870 5 103 Semantics in control direction 14 4 MODBUS SEMANTICS 15 4 1 COILS 15 4 2 INPUT...

Page 28: ... status input is being driven after which it returns to the previous group Edge triggered Level triggered Edge triggered Clock Sync From Status Real time clock may be synchronised using a status input See Clock Sync in Status Input Menu Disabled Seconds Minutes Minutes Operating Mode To allow access to change configuration files using Reylogic Toolbox the relay must be placed Out Of Service Local ...

Page 29: ...ed or disabled Disabled Enabled Disabled Trip Cct Fail 1 PU Delay Delay before trip circuit failure picks up Use in conjunction with STATUS INPUT MENU Trip Cct Fail 1 setting to configure which status inputs prevent this timer from operating 0 0 02 60 s 0 40 s Trip Cct Fail 2 Disabled Enabled Disabled Trip Cct Fail 2 PU Delay 0 0 02 60 s 0 40 s 1 6 Status Input Menu Description Range Default Setti...

Page 30: ...ux I P 2 Dropoff Delay 0 000 0 005 864000 s 0 s Aux I P 3 Pickup Delay 0 000 0 005 864000 s 0 s Aux I P 3 Dropoff Delay 0 000 0 005 864000 s 0 s Aux I P 4 Pickup Delay 1 0 000 0 005 864000 s 0 s Aux I P 4 Dropoff Delay 1 0 000 0 005 864000 s 0 s Aux I P 5 Pickup Delay 1 0 000 0 005 864000 s 0 s Aux I P 5 Dropoff Delay 1 0 000 0 005 864000 s 0 s Aux I P 6 Pickup Delay 1 0 000 0 005 864000 s 0 s Aux...

Page 31: ...864000 s 0 s Aux I P 27 Pickup Delay 1 0 000 0 005 864000 s 0 s Aux I P 27 Dropoff Delay 1 0 000 0 005 864000 s 0 s 1 Only when fitted 1 8 Reylogic Element Menu Description Range Default Setting Max Data Rec Time When a data record is triggered by a fault condition the relay stops recording information when either the triggering condition is removed or this timer expires whichever happens first 0 ...

Page 32: ... 29 1 NONE Aux I P 25 Operated 2 NONE 1 29 1 NONE Aux I P 26 Operated 2 NONE 1 29 1 NONE Aux I P 27 Operated 2 NONE 1 29 1 NONE Hand Reset Outputs Relays selected as Hand Reset will remain latched until manually reset from front panel or via communications link or by removing DC Supply By default relays are Self Resetting and will reset when the driving signal is removed NONE 1 29 1 NONE Protectio...

Page 33: ... 50 2 Phase A Overall Differential INST DTL Stage 2 Phase A element has operated NONE 1 32 2 5 87 50 2 Phase B NONE 1 32 3 5 87 50 2 Phase C NONE 1 32 4 5 CT 50 Phase A Overall Differential CT Supervision INST DTL Phase element has operated NONE 1 32 2 6 CT 50 Phase B NONE 1 32 3 6 CT 50 Phase C NONE 1 32 4 6 General Starter A starter element is picked up Useful when testing individual functions N...

Page 34: ...nds 2 Recs x 2 Seconds 1 Recs x 5 Seconds 5 Recs x 1 Second Trigger Waveform Triggers the waveform recorder NO YES NO Clear Waveforms Clears the waveform recorder NO YES NO 1 Number of records and duration available is dependent upon relay model 1 12 Communications Menu Description Range Default Setting Station Address IEC 60870 5 103 Station Address 0 254 0 COM1 Protocol Selects protocol to use f...

Page 35: ...ress down Start of Differential current meters Primary Currents 0 000 0 000 0 000 kA Differential Primary currents Secondary Currents 0 000 0 000 0 000 A Differential Secondary currents Nominal Currents 0 00 0 00 0 00 xIn Differential Nominal currents MISC METERS press down Start of miscellaneous meters Status Inputs 1 16 Displays the state of DC status inputs 1 to 16 1 Status Inputs 17 27 Display...

Page 36: ...70 1 Status Input 1 x 1 1 9 70 2 Status Input 2 x 1 1 9 70 3 Status Input 3 x 1 1 9 70 4 Status Input 4 x 1 1 9 70 5 Status Input 5 x 1 1 9 70 6 Status Input 6 x 1 1 9 70 7 Status Input 7 x 1 1 9 70 8 Status Input 8 x 1 1 9 70 9 Status Input 9 x 1 1 9 70 10 Status Input 10 x 1 1 9 70 11 Status Input 11 x 1 1 9 70 12 Status Input 12 x 1 1 9 70 13 Status Input 13 x 1 1 9 70 14 Status Input 14 x 1 1 ...

Page 37: ...rol Relay 20 x 1 1 9 80 21 Plant Control Relay 21 x 1 1 9 80 22 Plant Control Relay 22 x 1 1 9 80 23 Plant Control Relay 23 x 1 1 9 80 24 Plant Control Relay 24 x 1 1 9 80 25 Plant Control Relay 25 x 1 1 9 80 26 Plant Control Relay 26 x 1 1 9 80 27 Plant Control Relay 27 x 1 1 9 80 28 Plant Control Relay 28 x 1 1 9 80 29 Plant Control Relay 29 x 1 1 9 181 0 GI End 8 10 181 0 Time Synchronisation 6...

Page 38: ...tput Relay 1 ON 20 20 80 2 Energise Output Relay 2 ON 20 20 80 3 Energise Output Relay 3 ON 20 20 80 4 Energise Output Relay 4 ON 20 20 80 5 Energise Output Relay 5 ON 20 20 80 6 Energise Output Relay 6 ON 20 20 80 7 Energise Output Relay 7 ON 20 20 80 8 Energise Output Relay 8 ON 20 20 80 9 Energise Output Relay 9 ON 20 20 80 10 Energise Output Relay 10 ON 20 20 80 11 Energise Output Relay 11 ON ...

Page 39: ... 00001 Energise O P Relay 1 00002 Energise O P Relay 2 00003 Energise O P Relay 3 00004 Energise O P Relay 4 00005 Energise O P Relay 5 00006 Energise O P Relay 6 00007 Energise O P Relay 7 00008 Energise O P Relay 8 00009 Energise O P Relay 9 00010 Energise O P Relay 10 00011 Energise O P Relay 11 00012 Energise O P Relay 12 00013 Energise O P Relay 13 00014 Energise O P Relay 14 00015 Energise O...

Page 40: ...atus Input 21 10022 Status Input 22 10023 Status Input 23 10024 Status Input 24 10025 Status Input 25 10026 Status Input 26 10027 Status Input 27 10028 Status Input 28 10029 Status Input 29 10030 Status Input 30 10031 Status Input 31 10032 Status Input 32 Address Description 10101 Front Port Override 10102 Remote mode 10103 Service mode 10104 Local mode 10105 Local Remote 10111 Trip Circuit Fail 1...

Page 41: ...sters 32 bit fixed point a 32 bit integer containing a value to 3 decimal places e g 50000 sent 50 000 2 UINT16 1 register standard 16 bit unsigned integer 5 Reylogic Diagrams General Trip General_Trip PhaseA_Trip PhaseB_Trip PhaseC_Trip PhaseA_Starter CT_50_Starter1 A87_50_1_Starter1 PhaseB_Starter PhaseC_Starter IECEvent Code 181 64 IECEvent Code 181 65 IECEvent Code 181 66 IECEvent Code 181 84 ...

Page 42: ... DATA RECORDERLOGIC Select Group 1 SiSelectGroup1_Input SiSelectSettingGroup1 Select Group 2 SiSelectGroup2_Input SiSelectSettingGroup2 Select Group 3 SiSelectGroup3_Input SiSelectSettingGroup3 Select Group 4 SiSelectGroup4_Input SiSelectSettingGroup4 Select Group 5 SiSelectGroup5_Input SiSelectSettingGroup5 Select Group 6 SiSelectGroup6_Input SiSelectSettingGroup6 Select Group 7 SiSelectGroup7_In...

Page 43: ...tion Devices Limited Chapter 3 Page 19 of 20 6 Label Inserts DAD N 101 R15 DA1 101 E8 24 02 2010 12 55 00 1 GENERAL STARTER 2 PHASE A 3 PHASE B 4 PHASE C 5 87 50 DIFFERENTIAL 6 CT 50 CT SUPERVISION 7 74TC TRIP CIRCUIT FAIL 8 9 10 11 12 13 14 15 16 ...

Page 44: ... Page 20 of 20 DA1 101 THIS LABEL IS E12 E16 Left DELIBERATELY BLANK 24 02 2010 12 55 00 1 GENERAL STARTER 17 2 PHASE A 18 3 PHASE B 19 4 PHASE C 20 5 87 50 DIFFERENTIAL 21 6 CT 50 CT SUPERVISION 22 7 74TC TRIP CIRCUIT FAIL 23 8 24 9 25 10 26 11 27 12 28 13 29 14 30 15 31 16 32 ...

Page 45: ...be reproduced from this document unless Siemens Protection Devices Limited consent While the information and guidance given in this document is believed to be correct no liability shall be accepted for any loss or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemens Protection Devi...

Page 46: ...a Bits A number of bits containing the data Sent after the start bit Half Duplex Asynchronous Communications Communications in two directions but only one at a time Hayes AT Modem command set developed by Hayes Microcomputer products Inc IEC 60870 5 103 The International Electrotechnical Commission s Standard for communications with Protection Relays Master Station See primary station Modem MOdula...

Page 47: ...plant Reydisp Evolution can be configured to connect to the relays using RS232 Fibre Optic Modem or using Ethernet When Ethernet is used the IEC 60870 5 103 protocol is transported using the TCP IP protocol suite across a Local or Wide Area Network LAN WAN 3 Connection Specification and Relay Settings This section defines the connection medium as defined by IEC60870 5 103 Appendix A shows some typ...

Page 48: ...ltiple relay connections Each of the 30 fibre optic ports can be configured for either Light ON or Light OFF operation Default for all is OFF 3 6 Parity Setting IEC60870 5 103 defines the method of transmission as using EVEN Parity However in some instances an alternative may be required This option allows the parity to be set to NONE 3 7 Address Setting The address of the relay must be set to a v...

Page 49: ...8 and stop bits 1 Note although it may be possible to communicate with the modem at e g 19200bps it may not be possible to transmit at this rate over the telephone system which may be limited to 14400 A baud rate setting needs to be chosen which is compatible with the telephone system As 14400 is not available in the relay the next lowest rate 9600 would have to be used Since the modem needs to be...

Page 50: ... the fibre optic receiver port is automatically in hardware re transmitted from the transmitter port This is made possible because of the communications standard IEC 60870 5 103 which operates half duplex Personal Computer Classical SCADA EMS Remote Control Points Optical link Parallel hardwired connections clean contacts binary inputs 1 Dialogue type comms connection oriented 2 Dialogue for purpo...

Page 51: ...ore actual information exchange P S T N Modem Classical SCADA Personal Computer EMS Remote Control Points Optical link Parallel hardwired connections clean contacts binary inputs Personal Computer Modem Modem PSTN Public Switched Telephone Network Version of the former configuration of Figure 1 It is necessary to make dial up connection before actual information exchange P S T N Modem Classical SC...

Page 52: ...bstation can be accessed via one modem but only one can be communicated with at a time EMS Remote Control Points P S T N Fibre Optic Hub Multiplexer Modem Modem SIGMA 1 Figure 3 Star Type Configuration Using SIGMA 1 Multiplexer Personal Computer Personal Computer Modem PSTN Public Switched Telephone Network P S T N Modem Modem Serial optical link Tx Tx Tx Tx Tx Rx Rx Rx Rx Rx Figure 4 Optical Ring...

Page 53: ...terface Tx Rx Tx Rx Tx Rx Figure 5 Direct Control System Data Concentrator Configuration Fibre Optic Serial Loop Link Tx Tx Tx Tx Rx Rx Rx Rx Remote System Tx Rx Laptop computer Remote RS232 Local RS232 SIGMA 3 RS232 RS232 Figure 6 Automatic switchover remote to local control using the SIGMA 3 When a portable PC is plugged into the front port of a SIGMA 3 then the remote system is automatically di...

Page 54: ... UDS 10 or equiv Figure 7 LAN Network connectivity using a SIGMA 3 Lantronix UDS 10 or equivalent A SIGMA 3 unit may be used to as shown in Figure 7 to connect Argus and Modular II protection relays to a local area network via an Ethernet to RS232 convertor such as the Lantronix UDS 10 or similar device SIGMA 3 units may be used on a per bay or per substation basis They provide a single point of c...

Page 55: ...be reproduced from this document unless Siemens Protection Devices Limited consent While the information and guidance given in this document is believed to be correct no liability shall be accepted for any loss or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemens Protection Devi...

Page 56: ...gure 2 Simple 4 CT Protection 4 Figure 3 Current Distribution with one CT totally saturated 4 Figure 4 Stabilising Resistor 4 Figure 5 Measuring Lead Resistance 5 Figure 6 Non Linear Resistor 6 Figure 7 Shunt Resistor 7 Figure 8 Check Zone Relay 8 Figure 9 CTs Overlapping the CB 9 Figure 10 CTs on other side of CB 10 Figure 11 CTs on Busbar side of CB 10 Figure 12 CTs on Bus Section and Bus Couple...

Page 57: ... scheme is 20ms Busbar faults are almost always permanent faults and are therefore not suitable for Auto reclosure Instead every source connection to the Busbar must be broken and isolated 3 High Impedance Differential Protection In a High Impedance current differential scheme the secondary winding of the CTs positioned at all entry and exit points of a protected zone are summated external to the ...

Page 58: ...y resistance Rct and will be considerably larger than the resistance of the Relay analogue inputs This means that most of the unbalanced currents from the other CTs will flow through the Relay and these may be of sufficient magnitude to operate the protection Relay 0A 1A 2A 2A 1A Relay 2A 2A 1A 1A Rct Rrelay Figure 3 Current Distribution with one CT totally saturated The solution is to load the Re...

Page 59: ...ons If IMaxPriExtFault is not known the breaking capacity current of the Circuit Breaker can be used The value of Rstab must be such that the current flowing through the Relay at this voltage is less than the protection pick up setting Is Is must be chosen so that the protection will operate for all internal fault currents Sensitivity is achieved by ensuring that Is is such that the protection wil...

Page 60: ...IMaxPriIntFault is not known the breaking capacity current of the Circuit Breaker can be used Note that the stabilising resistor will have no effect until CT saturation occurs The CT secondaries act as current sources and any imbalance must go through the relay circuit despite the presence of Rstab 3 2 Non Linear Resistor For safety reasons overvoltages within a protection panel must not be allowe...

Page 61: ...ecification This of course would entail re calculating the value of Rstab The process is thus iterative until a suitable primary operate level is achieved As the number of paralleled CTs increases the losses through magnetising current become so large that it becomes impossible to set Is low enough At this point the scheme becomes unworkable As a very rough guideline the maximum number of parallel...

Page 62: ...rotecting each Busbar zone are then connected in series with the Check Zone relay s outputs Only when both operate will a trip be issued 106 104 186 184 Main 1 Res 206 204 286 284 Main 2 106 104 186 184 206 204 286 284 RESERVE MAIN 1 MAIN 2 Check 180 280 205 105 Figure 8 Check Zone Relay 2010 Siemens Protection Devices Limited Chapter 5 Page 8 of 16 ...

Page 63: ...es according to the type of switchgear In many cases the CTs are built into the Circuit Breakers In others they are separate devices located as close to the Breakers as possible 5 1 CTs overlapping the Circuit Breaker This arrangement is common in outdoor bulk oil types The performance of the protection is considered for the faults F1 to F4 A fault at F1 is a busbar fault which should be cleared b...

Page 64: ...operated so permitting the interlocked overcurrent relay to function and unstabilise the circuit unit protection or send an intertripping signal to the remote end of the circuit Figure 10 CTs on other side of CB 5 3 CTs on the Busbar side of the Circuit Breaker The faults at F1 and F2 will be correctly cleared A fault at F3 will cause the circuit protection to trip the circuit breaker but the faul...

Page 65: ...ceptable Once a CT Supervision condition has been detected the relay can be programmed to issue an alarm via one of the output contacts Where a mal operation is preferred to missing a real fault this alarm is used to simply alert the system operator to the condition It should then be rectified as soon as possible Where a mal operation is unacceptable however this alarm can be used to disable the p...

Page 66: ... Tx 2 Rx 2 I O2 ve 17 ve ve 19 21 BI12 ve ve 1 3 BI13 ve ve 5 7 BI14 ve ve 9 11 BI15 ve ve 13 15 BI16 BI17 23 ve ve 25 27 BI18 BI19 BO18 20 22 26 28 24 BO14 4 2 BO15 8 6 BO16 12 10 BO17 16 14 18 BO19 BO20 BO21 ve I O3 ve 17 ve ve 19 21 BI20 ve ve 1 3 BI21 ve ve 5 7 BI22 ve ve 9 11 BI23 ve ve 13 15 BI24 BI25 23 ve ve 25 27 BI26 BI27 BO26 20 22 26 28 24 BO22 4 2 BO23 8 6 BO24 12 10 BO25 16 14 18 BO2...

Page 67: ...osils Series stabilising resistors Discriminating CT Supervision Relay Zone Shorting Relay Trip Relay s PROTECTED ZONE Figure 14 Typical High Impedance Protection Components 2010 Siemens Protection Devices Limited Chapter 5 Page 13 of 16 ...

Page 68: ...abilising Resistors Relay Elements NLR All CTs should be the same Ratio and ideally have the same kneepoint voltage Figure 15 High Impedance Protection of Auto transformer 2010 Siemens Protection Devices Limited Chapter 5 Page 14 of 16 ...

Page 69: ...7SG12 DAD N Applications Guide RSTAB Relay Elements NLR Figure 16 High Impedance Protection of Motor Generator or Reactors 2010 Siemens Protection Devices Limited Chapter 5 Page 15 of 16 ...

Page 70: ... 2010 Siemens Protection Devices Limited Chapter 5 Page 16 of 16 Figure 17 DAD N 101 Differential Protection Elements DAD N 101 Single Zone Numerical High Impedance Differential 87 Ia 87 Ib 87 Ic CT50 1 87 50 1 1 AN1 C1 C3 87 50 1 2 ...

Page 71: ...reproduced from this document unless Siemens Protection Devices Limited consent While the information and guidance given in this document is believed to be correct no liability shall be accepted for any loss or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemens Protection Devices...

Page 72: ...allation Contents 1 Unpacking Storage Handling 3 2 Recommended Mounting Position 3 3 Relay Dimensions 3 4 Fixings 3 5 Ancillary Equipment 4 6 Precautions 4 2010 Siemens Protection Devices Limited Chapter 6 Page 2 of 4 ...

Page 73: ... potential as the relay by touching the case The module must not be handled by any of the module terminals on the rear of the chassis Modules must be packed for transport in an anti static container Ensure that anyone else handling the modules is at the same potential As there are no user serviceable parts in any module there should be no requirement to remove any component parts If any component ...

Page 74: ...is required The PC must be capable of running Microsoft Windows Ver 3 1 or greater and it must have a standard RS232 port A standard data cable is required to connect from the PC to the 25 pin female D type connector on the front of the relay For remote communications more specialised equipment is required See the section on Communications for further information and also see Report No 690 0 01 on...

Page 75: ... reproduced from this document unless Siemens Protection Devices Limited consent While the information and guidance given in this document is believed to be correct no liability shall be accepted for any loss or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemens Protection Device...

Page 76: ...sts 6 9 1 Accuracy of Measurement 6 9 2 Checking the Differential Element 6 10 Primary Injection Tests 7 11 Fault Setting Tests 7 11 1 Differential protections 7 12 Tripping and Intertripping Tests 7 13 Tests Using Load Currents 7 14 Putting into Service 8 List of Tables Table 1 Insulation Resistance Values 4 Table 2 Lead Resistance Values 5 Table 3 Accuracy of Measurement 6 Table 4 Differential E...

Page 77: ... test leads should not be used where the measurement of a current transformer C T secondary current is involved the failure or blowing of an instrument fuse or the operation of an instrument cut out could cause the secondary winding of the C T to become an open circuit Open circuit secondary windings on energised current transformers are a hazard that can produce high voltages dangerous to personn...

Page 78: ...iring to earth apply test connections between suitable points to short circuit each status input and series resistor to avoid possible damage to the opto coupler should the wiring be earthed c Test the power supply wiring to module PSU separately Note that the D C ve and D C ve are each connected to earth by surge capacitors Record the results in Table 1 Insulation Resistance Values Wiring Section...

Page 79: ...he Communications Settings in the relays must match the settings Communications settings selected in the Reydisp Evolution software To change the communications settings on the relay use the following procedure On the relay fascia keep tapping the Ø key until the COMMUNICATIONS MENU is displayed on the relay LCD Press the TEST RESET Ö once to bring up the STATION ADDRESS on the LCD Press the ENTER...

Page 80: ...onnected in accordance with the manufacturer s instructions By default all protection elements are disabled however if this is not the case then disable all protection and alarm elements 9 1 Accuracy of Measurement Inject all of the current inputs with nominal current in turn and record the following currents measured by the relay in Table 3 Accuracy of Measurement Tap Ø to select e g Diff Current...

Page 81: ... 1 Differential protections Isolate the auxiliary d c supplies for trip and alarm and remove the Trip and Intertrip links Check that the setting resistor is the correct ohmic value also that the correct Differential settings are selected Measure the primary current for operation of the CT and 87 50 elements and record the value obtained 12 Tripping and Intertripping Tests Re connect the auxiliary ...

Page 82: ... Ensure that The trip supply is connected All the RED LEDs are off The GREEN LED is ON steady All earth links trip links and inter trip links are in their normal operational positions Operate the Cancel PUSH BUTTON Check that the LCD displays the screen below or the Relay Identifier set in the SYSTEM CONFIG MENU DAD N Replace the cover The above reading will remain for approximately 1 hour then th...

Page 83: ...reproduced from this document unless Siemens Protection Devices Limited consent While the information and guidance given in this document is believed to be correct no liability shall be accepted for any loss or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemens Protection Devices...

Page 84: ...ked for operation during the normal maintenance period for the site on which the product is installed It is recommended the following tests are carried out 1 Visual inspection of the metering display every year 2 Operation of output contacts every 2 years 3 Secondary injection of each element every 5 years 2010 Siemens Protection Devices Limited Chapter 8 Page 2 of 3 ...

Page 85: ...repair V4 and current For collection products See prices in PMD Type of failure Device or module does not start up Mechanical problem Overload Sporadic failure Knock sensitive Transport damage Permanent failure Temperature caused failure Failure after ca hrs in use Repeated breakdown Failure after firmware update Error description Display message use separated sheet for more info Active LED messag...

Page 86: ...produced from this document unless Siemens Protection Devices Limited consent While the information and guidance given in this document is believed to be correct no liability shall be accepted for any loss or damage caused by any error or omission whether such error or omission is the result of negligence or any other cause Any and all such liability is disclaimed 2010 Siemens Protection Devices L...

Page 87: ...s Figures Figure 1 E8 Case Style Panel Cut out 3 Figure 2 E12 Case Style Panel Cut out 3 Figure 3 E16 Case Style Panel Cut out 4 Figure 4 Rear Terminal View 5 2010 Siemens Protection Devices Limited Chapter 9 Page 2 of 5 ...

Page 88: ...7SG12 DAD N Diagrams Figure 1 E8 Case Style Panel Cut out Figure 2 E12 Case Style Panel Cut out 2010 Siemens Protection Devices Limited Chapter 9 Page 3 of 5 ...

Page 89: ...7SG12 DAD N Diagrams Figure 3 E16 Case Style Panel Cut out 2010 Siemens Protection Devices Limited Chapter 9 Page 4 of 5 ...

Page 90: ...7SG12 DAD N Diagrams 2010 Siemens Protection Devices Limited Chapter 9 Page 5 of 5 B A C Figure 4 Rear Terminal View ...

Page 91: ... 180 524 24 71 Charges depending on provider E mail support energy siemens com Power Distribution Division Order No C53000 G7076 C15 1 Printed in Fürth Printed on elementary chlorine free bleached paper All rights reserved Trademarks mentioned in this document are the property of Siemens AG its affili ates or their respective owners Subject to change without prior notice The information in this do...

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