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Unread 13-11-2007, 03:02
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Re: Need help with clutch in drivetrain

Quote:
Originally Posted by Jon Jack View Post
Not entirely true. All a BLDC motor controller does is power the three phases in a particular order. For example, A-B-C in one direction or C-B-A in the opposite. What would you need a relay for? You don't need to reverse polarity to reverse direction.
All the brushless controllers I have been able to find (besides ones that are HUGE. several ounces and several hundred amps) only spin the motor one way. I simply can't find a dual direction brushless controller that is even remotely small enough ( < 1 oz and about 25-30 amp).

I was thinking I could make a singled irection into a dual direction by having a relay switch the motor leads. I'd then need a microcontroller to determine if the pwm is above or below neutral, and switch accordingly.

However, if you can point me to a dual direction brushless controller in a small size, I would be extremely happy.