Repulsion Start Induction Electric Motor (Reversible)
A repulsion start induction motor is a single phase motor having the same winding’s as a repulsion motor, but at a predetermined speed the rotor winding is short- circuited or otherwise connected to give the equivalent of a squirrel cage winding. This motor starts as a repulsion motor, but operates as an induction motor with constant speed characteristics. It has a single-phase distributed field winding with the axis of the brushes displaced from the axis of the field winding. The armature has an insulated winding. The current induced in the armature is carried by the brushes and commutator resulting in high starting torque. When nearly synchronous speed is reached, the commutator is short-circuited so that the armature is then similar in its functions to a squirrel cage armature.
The diagram depicts a reversible type that has two stator winding’s displaced as indicated. Reversal of the motor is accomplished by interchanging the field winding connections.