What are the working principles of a starting relay?

A starting relay is an electromagnetic switch used in electric motors, particularly in single-phase induction motors. It operates by using a coil that, when energized, creates a magnetic field to pull in a movable armature, closing the circuit to the starting winding of the motor. This allows the motor to start and gain speed. Once the motor reaches a certain speed, the relay opens the circuit to the starting winding, allowing the motor to run on its main winding alone.