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How do I know if an electric motor runs off AC or DC without running electricity through it?
The motor came off of a garage door opener and has a "starting capacitor".
4 Answers
- davidosterberg1Lv 62 decades agoFavorite Answer
Don't plug it into the AC outlet. All the previous answers miss a vital thought. A garage door motor has to turn both clockwise and counterclockwise to raise and lower the door. It could be AC with two sets of windings, or it could be DC with a transformer and bridge rectifiers. I'm betting its AC, but I'm also betting it isnt a simple 120V single phase motor.
- Anonymous2 decades ago
dc motors have brushes that contact the rotor
your motor is ac
dc will not flow across a cap
and there would be no reason to use a dc motor
off house ac power, it would be wasteful
and the rectifier is extra
and the motor costs more
Source(s): The purpose of a start cap is to reduce the starting current of a motor starting under load - Anonymous2 decades ago
ac if start cap
old and tired
get a new one
