Why would a brushless moter get "sticky?"
04-20-2007, 04:45 PM
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Why would a brushless moter get "sticky?"
I have a couple of different brushless motors that have this problem; both fairly new. When I turn them by hand, the occasionally seem to bind, or not really turn as easily as they should. The one I powered it up, and now it seems okay. The other is intemittant, but I'm afraid to fly it until I know what's going on. There isn't anything stuck in the bell or anything rubbing from what I can tell, although it sure feels like it. What might cause this?
04-20-2007, 05:15 PM
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RE: Why would a brushless moter get "sticky?"
I am not sure if this is what is happening with you or not, but I have noticed that the brushless motors spin freely before running them, then after running them they are much tighter. It has something to do with the current/voltage, they loosen up again after a few minutes once the current/voltage dimenishes.
04-20-2007, 07:55 PM
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RE: Why would a brushless moter get "sticky?"
It's the other way around, tight before running, loose after. The one seems to be okay, but I have another one that keeps doing it...very strange.
04-21-2007, 08:05 AM
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RE: Why would a brushless moter get "sticky?"
If your brushless motor is a bit stiff after running, it probably is due to the capacitors on the speed controll still holding a charge. I wondered about this with my first brushless motor and thought I had a bearing problem. One day I happened to plug in the battery momentarily but not run the motor, whatdyaknow the motor was "sticky" for about 5 minutes, that's when the little light in my brain lit up (or was it the light in my little brain, whatever
) apparently there is a little braking action from the charge on the caps.
Good luck,
Pete
) apparently there is a little braking action from the charge on the caps.Good luck,
Pete
04-22-2007, 12:11 PM
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RE: Why would a brushless moter get "sticky?"
What Caps? Are you referring to the ones on the ESC? I've never seen a brushless motor with caps across the terminals. Could it be that once an electrical field is placed across the armature there is an opposing magnetic field set up against the permanent magnets?
04-22-2007, 05:09 PM
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RE: Why would a brushless moter get "sticky?"
The input capacitors on the ESC apparently hold a charge for a short time, as I stated in my prior post all my brushless motors with CC controllers do this, all you have to do is plug in the battery momentarily, and you will the motor get draggy for a short time, does it every time, feels like a very light braking action.
Pete
Pete
