Single Phase AC Induction Motors

Single phase induction motors are used in residential and commercial applications where three phase power isn't available.

Eighty percent of operating motors in the United States are AC single phase induction motors. They are used in applications with power requirements of 10 horsepower or less.

AC single phase induction motors are classified by their start and run characteristics. An auxiliary starter winding is placed at right angles to the main stator winding in order to create a magnetic field. The current moving through each winding is out of phase by 90 degrees. This is called phase differential. After the motor has reached approximately 75% of operating speed, the auxiliary winding is disconnected from the circuit by a centrifugal switch.

And Furthermore . . .