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BLDC runs faster forward than reverse

Posted: Wed Jan 12, 2022 9:29 pm
by ndemarco
BLDC motor runs faster in the positive direction. When running in reverse, it draws substantially more current.

Using the Velocity controller currently. v1.9x. Motor is 42DMW61. My power supply is current limited to 4.5A, and in reverse, no load, it comes close to the limit. In forward, it doesn't approach 1A. Supply voltage is 12-24V.

Re: BLDC runs faster forward than reverse

Posted: Fri Jan 14, 2022 4:48 pm
by jdecoux
Are you certain your wires are hooked up correctly? There are several ways to wire up a BLDC motor, some of which will almost look like they're working, but won't behave nearly as efficiently as expected.

Re: BLDC runs faster forward than reverse

Posted: Tue Jan 18, 2022 11:30 pm
by ndemarco
Turns out it's an oddly configured motor. Not only are the ABC phases reversed, but the PID parameters must be specified as *(-1).
Note: Because of the way this motor is built, you'll need to set negative P, I and D values when using the MotorPositionController object.
https://www.phidgets.com/?tier=3&catid= ... rodid=1077