we are operationing 3NOs 800 Kva generators by
singronyus.specialey evening time our panel trip. the panel
showing generator earth fault
Answers were Sorted based on User's Feedback
Answer / k.prakashchandra
Which relay ? SEFR or back -up EFR ? Are the gens connected
to grid ? Whether all the gens trip simultaneously ?
Whenever there is a momentary heavy earth fault in the
outgoing feeder,all the gens trip on back-up EFR with
instantaneous trip indication,though the line does not
trip.So ,it is advised to disable instantaneous fault trip
i.e. high-set of the back-up EFR.
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / k.prakashchandra
Another probability. If there is any earth fault before the
GT primary bushings ,the gen may trip on SEFR if voltage
based( open delta) relay is used.Then you have to check
cable,termination glands and the stator winding for earth
fault either by meggering or better by applying rated voltage.
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / biplab
check the stator insulation with megger of each gen........
Is This Answer Correct ? | 1 Yes | 1 No |
Answer / ronnie
this might be the result accumulation of moisture near the
earthing bit during evening time.which causes the generator
to trip showing earth fault....
Is This Answer Correct ? | 0 Yes | 0 No |
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