7SR18 Performance Specification
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Contents
Section 1: Common Functions ............................................................................................................................ 5
1.1 General ............................................................................................................................................. 5
1.1.1 CE Conformity...................................................................................................................... 5
1.1.2 Reference ............................................................................................................................ 5
1.1.3 Accuracy Reference Conditions ............................................................................................ 5
1.1.4 Dimensions .......................................................................................................................... 5
1.1.5 Weights ............................................................................................................................... 5
1.2 Energising Quantities ......................................................................................................................... 6
1.2.1 Auxiliary Power Supply ......................................................................................................... 6
1.2.2 AC Analogue Current ........................................................................................................... 7
1.2.3 AC Analogue Voltage ........................................................................................................... 7
1.2.4 Binary (Digital) Outputs ........................................................................................................ 8
1.2.5 Binary (Digital) Inputs ........................................................................................................... 8
1.3 Functional performance ..................................................................................................................... 9
1.3.1 Instrumentation .................................................................................................................... 9
1.3.2 Real Time Clock ................................................................................................................... 9
1.4 Data Communication Interfaces ....................................................................................................... 10
1.4.1 USB 2.0 Data Communication Interface .............................................................................. 10
1.4.2 RS485 Data Communication Interface ................................................................................ 10
1.4.3 Fibre Optic Ethernet Data Communication Interface (IEC61850 Option) ............................... 10
1.4.4 Electrical Ethernet Data Communication Interface (IEC61850 Option) .................................. 10
1.5 Protection Interfaces and Connections ............................................................................................. 11
1.5.1 Differential Protection ......................................................................................................... 11
1.5.2 Protection Interfaces .......................................................................................................... 11
1.6 Environmental Performance ............................................................................................................. 13
1.6.1 General .............................................................................................................................. 13
1.6.2 Emissions .......................................................................................................................... 14
1.6.3 Immunity ............................................................................................................................ 15
1.6.4 Mechanical ........................................................................................................................ 17
Section 2: Protection Functions ........................................................................................................................ 18
2.1 37 Undercurrent............................................................................................................................... 18
2.1.1 Reference .......................................................................................................................... 18
2.1.2 Operate and Reset Level .................................................................................................... 18
2.1.3 Operate and Reset Time .................................................................................................... 18
2.2 46 Negative Phase Sequence Overcurrent ....................................................................................... 19
2.2.1 Reference (46DT) .............................................................................................................. 19
2.2.2 Operate and Reset Level (46DT) ........................................................................................ 19
2.2.3 Operate and Reset Time (46DT) ......................................................................................... 19
2.2.4 Reference (46IT) ................................................................................................................ 19
2.2.5 Operate and Reset Level (46IT) .......................................................................................... 19
2.2.6 Operate and Reset Time (46IT) .......................................................................................... 20
2.3 49 Thermal Overload ....................................................................................................................... 21
2.3.1 Reference .......................................................................................................................... 21
2.3.2 Operate and Reset Level .................................................................................................... 21
2.3.3 Operate and Reset Time .................................................................................................... 21
2.4 50 Instantaneous Overcurrent .......................................................................................................... 23
2.4.1 Reference .......................................................................................................................... 23
2.4.2 Operate and Reset Level .................................................................................................... 23
2.4.3 Operate and Reset Time .................................................................................................... 23
2.5 50G Instantaneous Measured Earth Fault ......................................................................................... 24
2.5.1 Reference .......................................................................................................................... 24
2.5.2 Operate and Reset Level .................................................................................................... 24
2.5.3 Operate and Reset Time .................................................................................................... 24
2.6 50N Instantaneous Derived Earth Fault ............................................................................................ 25
2.6.1 Reference .......................................................................................................................... 25
2.6.2 Operate and Reset Level .................................................................................................... 25
2.6.3 Operate and Reset Time .................................................................................................... 25
2.7 51 Time Delayed Overcurrent .......................................................................................................... 26