4
Second harmonic restraint - 2ndh-REST (H, L, T) ................................................................................................................................... 28
Trip Circuit Supervision - 74TCS (H, L, T) .................................................................................................................................................. 28
Selective block - BLOCK2 ........................................................................................................................................................................... 28
Internal selective block - BLOCK4 ............................................................................................................................................................. 28
Breaker failure - BF (L H T) ......................................................................................................................................................................... 28
Circuit Breaker supervision (H, L, T) ......................................................................................................................................................... 29
CT supervision - 74CT (H, L, T) .................................................................................................................................................................... 29
Demand measures ....................................................................................................................................................................................... 29
Oscillography (DFR) ..................................................................................................................................................................................... 29
Arc Flash ........................................................................................................................................................................................................ 30
3.9 METERING......................................................................................................................................................................................................... 30
Accuracy ........................................................................................................................................................................................................ 30
— 4 FUNCTION CHARACTERISTICS 31
4.1 HARDWARE .......................................................................................................................................................................................................31
Power supply board ...................................................................................................................................................................................... 31
CPU module .................................................................................................................................................................................................... 31
Input board .....................................................................................................................................................................................................32
MMI (Display, Keyboard and LED) .............................................................................................................................................................32
4.2 FIRMWARE ........................................................................................................................................................................................................ 33
Base software ............................................................................................................................................................................................... 33
Real-time operating system ........................................................................................................................................................................ 33
Task ................................................................................................................................................................................................................. 33
Drivers .............................................................................................................................................................................................................34
Application Software ....................................................................................................................................................................................34
Data Base .......................................................................................................................................................................................................34
Self test (Application) ...................................................................................................................................................................................34
Development tool (Builder) ..........................................................................................................................................................................34
4.3 I/0 DESCRIPTION ..............................................................................................................................................................................................35
Metering inputs .............................................................................................................................................................................................35
Conventions ................................................................................................................................................................................................... 40
Use of measured signals ............................................................................................................................................................................. 43
Binary inputs ..................................................................................................................................................................................................44
Output relays ................................................................................................................................................................................................. 49
LED indicators ............................................................................................................................................................................................... 50
Communication interfaces .......................................................................................................................................................................... 53
4.4 PROTECTIVE ELEMENTS .................................................................................................................................................................................54
Rated values ...................................................................................................................................................................................................54
Overflux - 24 .................................................................................................................................................................................................. 59
Thermal protection with RTD thermometric probes - 26 ........................................................................................................................66
Undervoltage - 27 ......................................................................................................................................................................................... 68
Undercurrent - 37 (H, L, T) ............................................................................................................................................................................72
Negative sequence overcurrent for Line or Transformer protection - 46 (H, L, T) .............................................................................74
Thermal image - 49LT for Line or Transformer protection (H, L, T) ....................................................................................................... 80
Negative sequence current / positive sequence current ratio - I2/I1 (H, L, T) ...................................................................................91
Phase overcurrent - 50/51 (H, L, T) .............................................................................................................................................................94
Residual overcurrent - 50N.1/51N.1, 50N.2/51N.2 or high impedance restricted earth fault - 87NHIZ.1, 87NHIZ.2 side 1,2 ....104
Residual overcurrent - 50N(Comp)/51N(Comp) side H or side L
.........................................................................................................115
Overvoltage - 59
...........................................................................................................................................................................................125
Residual overvoltage - 59N ....................................................................................................................................................................... 129
Low impedance restricted ground fault- 64REF .................................................................................................................................... 133
Overfrequency - 81O ...................................................................................................................................................................................136
Underfrequency - 81U
............................................................................................................................................................................... 138
Differential protection 87G-87M-87T
........................................................................................................................................................141
Breaker failure - BF (H, L, T) ......................................................................................................................................................................155
4.5 CONTROL AND MONITORING ......................................................................................................................................................................157
Remote tripping (1, 2, 3) .............................................................................................................................................................................. 157
Second Harmonic Restraint - 2ndh-REST (H, L, T)
................................................................................................................................ 158
CT supervision - 74CT (H, L, T)
.................................................................................................................................................................. 159
Trip circuit supervision - 74TCS (H, L, T) ................................................................................................................................................. 160
Virtual I/O ..................................................................................................................................................................................................... 163
Circuit breaker supervision .......................................................................................................................................................................166
Oscillography
.............................................................................................................................................................................................. 168
Arc Flash Protection
.................................................................................................................................................................................. 169
— 5 MEASURES, LOGIC STATES AND COUNTERS 170
Measures ..................................................................................................................................................................................................... 170
Protections
...................................................................................................................................................................................................171
Delayed inputs .............................................................................................................................................................................................171
Self test .........................................................................................................................................................................................................171
XMR-T EQUIPMENT MANUAL
Ed. 2.9 - 02/2021