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350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
Current sensing.........................................................................................................................6 - 25
Voltage sensing ........................................................................................................................6 - 26
Power system............................................................................................................................6 - 28
Breaker..........................................................................................................................................6 - 28
User curve ...................................................................................................................................6 - 29
FlexCurves...................................................................................................................................6 - 30
Time overcurrent curves.......................................................................................................6 - 31
Phase timed overcurrent (51P) ..........................................................................................6 - 40
Phase instantaneous overcurrent protection (50P).................................................6 - 43
Phase directional (67P) ..........................................................................................................6 - 45
Ground/Sensitive Ground timed overcurrent protection (51G/SG) ..................6 - 48
Ground/Sensitive Ground instantaneous overcurrent protection (50G/SG) 6 - 51
Ground directional (67G/SG)...............................................................................................6 - 53
Neutral timed overcurrent (51N).......................................................................................6 - 58
Negative sequence timed overcurrent protection (51_2).....................................6 - 61
Neutral instantaneous overcurrent protection (50N) .............................................6 - 64
Neutral directional (67N).......................................................................................................6 - 66
Negative sequence instantaneous overcurrent (50_2)..........................................6 - 71
Phase undervoltage (27P) ....................................................................................................6 - 73
Phase overvoltage (59P) .......................................................................................................6 - 76
Neutral overvoltage (59N)....................................................................................................6 - 78
Negative sequence overvoltage (59_2).........................................................................6 - 80
Auxiliary undervoltage (27X)...............................................................................................6 - 82
Auxiliary overvoltage (59X)..................................................................................................6 - 85
Underfrequency (81U) ........................................................................................................... 6 - 87
Overfrequency (81O) ..............................................................................................................6 - 89
Thermal Overload (49)............................................................................................................6 - 91
Wattmetric ground fault (32N)...........................................................................................6 - 95
Directional power (32)............................................................................................................6 - 99
Broken conductor (I1/I2 or 46BC) .....................................................................................6 - 103
Positive sequence undervoltage (27_1).........................................................................6 - 106
Volts per Hertz (24) ..................................................................................................................6 - 109
Change setpoint group .........................................................................................................6 - 115
Virtual inputs ..............................................................................................................................6 - 118
Logic elements ..........................................................................................................................6 - 118
Breaker control .........................................................................................................................6 - 131
Cold load pickup (CLP)............................................................................................................6 - 132
Breaker failure (50BF).............................................................................................................6 - 135
CT failure (60CTS)......................................................................................................................6 - 137
Autorecloser (79).......................................................................................................................6 - 139
Synchrocheck (25) ...................................................................................................................6 - 145
Second harmonic inhibit.......................................................................................................6 - 150
Lockout (86).................................................................................................................................6 - 152
VT fuse fail (VTFF or 60VTS)..................................................................................................6 - 154
Arc flash protection.................................................................................................................6 - 155
Contact inputs...........................................................................................................................6 - 158
Output relays .............................................................................................................................6 - 159
Output Relay 1 "Trip" .............................................................................................................6 - 159
Output Relay 2 "Close"..........................................................................................................6 - 161
Auxiliary Output Relays 3 to 6 ..........................................................................................6 - 163
Critical Failure Relay #7.......................................................................................................6 - 163
Virtual inputs ..............................................................................................................................6 - 166
Remote inputs ...........................................................................................................................6 - 167