What is the function of the potential relay?

The potential relay, often used in single-phase motors, functions to disconnect the starting circuit once the motor reaches a predetermined speed. It does this by sensing the voltage across the motor's start winding; when the voltage drops to a specific level indicating the motor is running, the relay opens the circuit to the start winding, preventing overheating and damage. This ensures efficient operation of the motor by allowing it to transition from starting to running mode seamlessly.