How many contactors are typically included in reversing starters?

Reversing starters are designed to control the direction of a motor's rotation, which requires the use of two contactors. Each contactor is responsible for reversing the phases of the supply voltage to the motor, thereby allowing it to rotate in both directions.

In a standard configuration, one contactor is used to connect the motor to one phase configuration, while the second contactor switches the connections to another phase configuration, effectively reversing the motor's direction of rotation. Since the operation of the motor must be safeguarded against overload conditions, a single overload relay assembly is typically included to protect the motor.

Having one overload relay assembly is sufficient because it can monitor the current flowing through the motor regardless of the direction in which it is rotating, as it is concerned with the overall load being fed to the motor. Thus, the correct configuration for a reversing starter includes two contactors to allow for direction reversal and one overload relay assembly for motor protection.