Thread: Cim Motor Help
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Unread 13-03-2014, 13:51
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Re: Cim Motor Help

Quote:
Originally Posted by Danny Diaz View Post
My first step for you would be to test swapping the polarity of the motor leads on the speed controller and then running the motor in the "up" direction again, and seeing if the motor then drives down. If so, you can look to the speed controller as a possible issue (if you use a different speed controller, such as one you're using for your drive system, does it then work?) - Have you actually used a multimeter to see how much voltage is supplied to the motor when driving down, or does the LED turn red when you drive down? But the first thing I'd do is test swapping polarity to ensure there's not a mechanical reason for it to not be driving downwards.

Or, have you tried putting 12V directly to the motor yet (without going through a speed controller)? If you're confident the motor should be able to go in the "down" direction, we usually just put 12V directly to the motor in order to test the mechanisms. We have a setup we use where we can plug in a 12V battery and also connect motor leads (with 'gator clips) that uses a momentary switch to energize the clips so that we can test mechanisms before we have the control systems completed.

-Danny
I'd go through the same process listed by Danny to do an initial diagnosis, it'll help you narrow the problem down to either the motor or the speed controller, if it's the motor, then swap it out and you should be good to go, but if it's the speed controller, things might get tricky.

Depending on the speed controllers used, the issue could be improper calibration and/or them not being calibrated at all. IIRC, Talon's ship without being calibrated, but I'm unsure of both Jags and Victors, although it wouldn't surprise me if the calibration were off... If the calibration is off, your zero may not actually be zero, it could be some amount in either direction from there, meaning that when you give a signal in the opposite direction, it might not be able to overcome the resistance on the motor since it'll only be at partial output - we actually had this exact problem at our first event, and it's a weird one to chase.
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