Single-Phase Induction Motors
The single-phase engine operates beneath the same principle as the polyphase electric motor, except that the rotating magnetic field effect generated by the stator does not exist until running rpm is reached. Since no starting torque is offered, a design mechanism is included to begin the motor. They are the various designations:
Torque-Speed Curves of Different Single-Phase Induction Motors
Shaded-pole: Have only one main winding and no begin winding. This configuration causes a shift of the applied magnetic field in romantic relationship to the rotor, creating stating torque. Applications include followers and small appliances.
Split-Phase (induction start motor)
Has two sets of stator windings. The “start” windings sit 90 degrees to the “run” windings and change the magnetic field of the stator, inducing starting torque. Applications include little grinders, small supporters, and blowers.
Capacitor-Start
The most common single-phase motor found in industrial applications. It is a altered split-phase motor with a capacitor in series with the start winding to provide a start boost. App include small conveyors, large blowers, pumps, and direct-drives.
Permanent-Split-Capacitor (PSC)
Uses identical main and auxiliary windings with a capacitor to supply starting torque. They are the most reliable single-phase engine because no chain sprocket centrifugal beginning switch is necessary. Applications include supporters and pumps in HVAC and refrigeration industries.