Single-Phase Induction Motors
The single-phase engine operates beneath the same principle as the polyphase engine, except that the rotating magnetic field effect produced by the stator will not exist until running rpm is reached. Since no starting torque is obtainable, a design system is included to start the motor. These are the various designations:
Torque-Speed Curves of Different Single-Phase Induction Motors
Shaded-pole: Have only 1 main winding and no start winding. This configuration causes a change of the applied magnetic field in romantic relationship to the rotor, creating stating torque. Applications include followers and small appliances.
Split-Phase (induction start electric motor)
Has two units of stator windings. The “start” windings sit 90 degrees to the “run” windings and change the magnetic field of the stator, inducing beginning torque. Applications include little grinders, small followers, and blowers.
Capacitor-Start
The most typical single-phase motor used in industrial applications. It is a altered split-phase engine with a capacitor in series with the beginning winding to chain sprocket provide a start boost. App include small conveyors, large blowers, pumps, and direct-drives.
Permanent-Split-Capacitor (PSC)
Uses identical primary and auxiliary windings with a capacitor to provide starting torque. They are the most reliable single-phase motor because no centrifugal beginning switch is required. Applications include fans and pumps in HVAC and refrigeration industries.