GE L90

vi L90 LINE CURRENT DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
TABLE OF CONTENTS
5.5.3 Signal sources .................................................................................................................. 5-139
5.5.4 87L power system .......................................................................................................... 5-142
5.5.5 Breakers .............................................................................................................................. 5-150
5.5.6 Disconnect switch control .......................................................................................... 5-155
5.5.7 FlexCurves.......................................................................................................................... 5-160
5.5.8 Phasor Measurement Unit.......................................................................................... 5-167
5.6 FlexLogic.............................................................................................................. 5-187
5.6.1 FlexLogic operands........................................................................................................ 5-187
5.6.2 FlexLogic rules.................................................................................................................. 5-203
5.6.3 FlexLogic evaluation...................................................................................................... 5-204
5.6.4 FlexLogic example..........................................................................................................5-204
5.6.5 FlexLogic equation editor............................................................................................ 5-209
5.6.6 FlexLogic timers............................................................................................................... 5-209
5.6.7 FlexElements ..................................................................................................................... 5-209
5.6.8 Non-volatile latches.......................................................................................................5-214
5.7 Grouped elements............................................................................................. 5-216
5.7.1 Overview ............................................................................................................................. 5-216
5.7.2 Setting group 1................................................................................................................. 5-216
5.7.3 Line differential elements............................................................................................ 5-217
5.7.4 Line pickup ......................................................................................................................... 5-222
5.7.5 Distance............................................................................................................................... 5-224
5.7.6 Power swing detect (ANSI 68).................................................................................... 5-245
5.7.7 Load encroachment ...................................................................................................... 5-254
5.7.8 Phase current ................................................................................................................... 5-255
5.7.9 Neutral current................................................................................................................. 5-267
5.7.10 Wattmetric ground fault.............................................................................................. 5-275
5.7.11 Ground current ................................................................................................................ 5-279
5.7.12 Negative sequence current........................................................................................ 5-286
5.7.13 Breaker failure (ANSI 50BF)......................................................................................... 5-292
5.7.14 Voltage elements ............................................................................................................ 5-302
5.7.15 Supervising elements.................................................................................................... 5-314
5.7.16 Sensitive directional power........................................................................................ 5-321
5.8 Control elements ............................................................................................... 5-324
5.8.1 Overview ............................................................................................................................. 5-324
5.8.2 Trip bus ................................................................................................................................ 5-324
5.8.3 Setting groups .................................................................................................................. 5-326
5.8.4 Selector switch................................................................................................................. 5-328
5.8.5 Trip output.......................................................................................................................... 5-334
5.8.6 Underfrequency (ANSI 81U)........................................................................................ 5-340
5.8.7 Overfrequency (ANSI 81O) .......................................................................................... 5-341
5.8.8 Synchrocheck (ANSI 25) ............................................................................................... 5-342
5.8.9 Digital elements............................................................................................................... 5-347
5.8.10 Digital counters................................................................................................................ 5-350
5.8.11 Monitoring elements ..................................................................................................... 5-352
5.8.12 Pilot schemes.................................................................................................................... 5-376
5.8.13 Autoreclose (ANSI 79).................................................................................................... 5-399
5.8.14 Frequency rate of change (ANSI 81R).................................................................... 5-412
5.9 Inputs/outputs ................................................................................................... 5-413
5.9.1 Contact inputs.................................................................................................................. 5-413
5.9.2 Virtual inputs ..................................................................................................................... 5-415
5.9.3 Contact outputs............................................................................................................... 5-416
5.9.4 Virtual outputs.................................................................................................................. 5-420
5.9.5 Direct inputs and outputs ........................................................................................... 5-420
5.9.6 Resetting ............................................................................................................................. 5-421
5.10 Transducer inputs/outputs.............................................................................. 5-422
5.10.1 DCmA inputs...................................................................................................................... 5-422