Schweitzer Engineering SEL-351P, Quick Start Manual

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F-4 Setting Negative-Sequence Overcurrent Elements Date Code 990215
SEL-351P Manual Técnico
Figure APPENDIX F: .2: Distribution Feeder Protective
Devices
I
F
= Maximum load current through feeder relay = 450 A
I
R
= Maximum load current through line recloser = 150 A
51F = Feeder relay phase time-overcurrent element
51QF = Feeder relay negative-sequence time-overcurrent element
51R = Line recloser phase time-overcurrent element (phase “slow curve”)
Traditional Phase Coordination
Figure APPENDIX F: .3: Traditional Phase Coordination
51F: pickup = 600 A (above max. feeder load, I
F
)
51R: pickup = 200 A (above max. line recloser load, I
R
)