Motor Tripping part 2
Motor Tripping part 2
(OP)
What is the possible cause of breaker tripping of motors when the motor is decelerating (not in full stop) and when you try to start again, the motor protection will trip?
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RE: Motor Tripping part 2
RE: Motor Tripping part 2
GO PLACIDLY, AMIDST THE NOISE AND HASTE-Desiderata
RE: Motor Tripping part 2
Also, if the motor has been coasting for a minute and still trips on a re-start then it is not the back emf. The back emf should have decayed within about 5 seconds even for a large motor.
If the motor is not tripping on the back emf then you should take a look at the cause of the trip.
RE: Motor Tripping part 2
Regards.
Slava
RE: Motor Tripping part 2
That's within a few seconds of disconnecting the motor. It acts as generator. Then as you reclose the contactor on it while it's still spinning you are hooking up a generator,(sort of), that may be,(likely is), wildly out of phase with the supply.
This can damage things and certainly cause a breaker to trip.
If you mean the motor slows to a stop and then you reclose it and get a trip then were are talking something else.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Motor Tripping part 2
GO PLACIDLY, AMIDST THE NOISE AND HASTE-Desiderata
RE: Motor Tripping part 2
Motors with direct connected capacitors and overhauling loads are one example.
Bill
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"Why not the best?"
Jimmy Carter
RE: Motor Tripping part 2
GO PLACIDLY, AMIDST THE NOISE AND HASTE-Desiderata
RE: Motor Tripping part 2
RE: Motor Tripping part 2
GO PLACIDLY, AMIDST THE NOISE AND HASTE-Desiderata