Author Topic: 10 kW motor 72 volt phase resistance  (Read 2093 times)

Offline MarkLyons

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10 kW motor 72 volt phase resistance
« on: February 28, 2023, 09:52:00 PM »
Hello
What should the resistance of the phase to phase be.
My bike periodically turns off when I back the throttle off, but is ok once I turn it off and on again. Noticed it beeps 3 times when this happens which says phase to phase short circuit.
Bike still runs well.

Offline Bikemad

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Re: 10 kW motor 72 volt phase resistance
« Reply #1 on: March 04, 2023, 01:59:05 PM »
Hi Mark

According to the GM website, the Phase Resistance for the 72V 10kW motor is 6.0 Milliohms and the Phase Induction should be 77uH @ 100kHz, but I think that is for both sets of phase wires connected in parallel.
If measured separately, I would expect it to be 12.0 Milliohms and 154uH @ 100kHz (the same as the 5kW motor).

Ideally, the six resistance readings measured between each pair of Phase wires on each or the stators should be identical. If the resistance readings from one stator are significantly different to the other stator then you might have a problem with one of the stators (but this is most unlikely).

There should also be no continuity between any of the Phase wires and the Battery +ve and Battery -ve terminals when all six Phase wires are connected to their respective Phase terminals on the controller.

Have you tried running the motor on the other set of Hall Sensors to see if the problem disappears?

It might be worth checking the voltage on the throttle signal wire (relative to Battery -ve) to make sure it is not below the value of the Throttle lowest allowed voltage (V) setting when the throttle is released.

Alan