How to Rewire a Motor

How to Rewire a Motor

I would like to reverse the direction of a bench saw motor, which I bought at an auction. I believe to do this, it is necessary to reverse the field coil leads. How can I identify the correct leads?

Simon Watts: There may be a wiring diagram inside the terminal box cover. If not, I suggest you leave it to someone who knows what he or she is doing.

Rob Johnstone: Why are you doing this? Don’t.

Ok, I know that an electric motor does not care which way it turns, but most 120-volt motors have a starter on them that gets the whole contraption turning in a specific direction. Changing the direction of a 120-volt saw motor’s rotation may indeed be impossible, depending on the type of motor construction. The most common sense solution to the problem would be to take the motor to an electric motor repair shop and have them do it. Changing the rotation on a three-phase motor, on the other hand, is a piece of cake. Just swap the two legs of three wires going into the saw, which are not the high leg. There is usually a diagram on the saw to aid you in your quest. If you don’t know which leg is which…revert to my earlier advise.

Posted in: