Single-Phase Induction Motors
The single-phase motor operates under the same principle as the polyphase engine, except that the rotating magnetic field effect generated by the stator does not exist until running rpm is reached. Since no starting torque is obtainable, a design system is included to start the motor. They 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 shift of the used magnetic field in relationship to the rotor, creating stating torque. Applications consist of enthusiasts and small appliances.
Split-Phase (induction start engine)
Has two sets of stator windings. The “start” windings are positioned 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.
The most common single-phase motor used in industrial applications. It is a modified split-stage motor with a capacitor in series with the start winding to supply a start boost. Application include small conveyors, large blowers, pumps, and direct-drives.
Uses identical main and auxiliary windings with a capacitor to provide starting torque. They are the most reliable single-phase motor sprockets because no centrifugal beginning switch is required. Applications include enthusiasts and pumps in HVAC and refrigeration industries.