What causes a single phase motor to run backwards?
There are 3 basic types of electrical motors: DC, single phase AC and 3 phase AC. Switching the polarity of the input voltage will cause a simple DC motor to run in the reverse direction. Switching the starter winding leads will cause a single phase AC motor to run in reverse.
How can the direction of rotation of a split phase motor be reversed?
To reverse it, we need to change the direction of the rotating magnetic field produced by the main and starter windings. And this can be accomplished by reversing the polarity of the starter winding. If you were to switch the main and starter windings, as one does with a split phase motor, the motor will also reverse.
Can a bad run capacitor cause a motor to run backwards?
Watch out: yes it is indeed possible for some electric motors to run “backwards” following damage to the motor’s start capacitor or windings. We’ve had an occasional report of an HVAC motor running “the wrong way” or sometimes starting to run the the wrong way.
How do you reverse the direction of a single phase motor?
To reverse rotation on a single phase capacitor start motor, you will need to reverse the polarity of the starter winding. This will cause the magnetic field to change directions, and the motor will follow. In order to achieve this, you can swap the connections on either end of the winding.