Which component is used to protect against overloads in a motor circuit?

The component used to protect against overloads in a motor circuit is the overload relay. An overload relay is specifically designed to monitor the current flowing through a motor. When the current exceeds a predetermined threshold due to an overload condition, the overload relay opens the circuit and disconnects power to the motor, thus preventing potential damage that could result from overheating or excessive current draw.

Overload relays function as a protection method against overheating by sensing the thermal conditions that arise from excessive current, allowing them to react and protect the motor. This is essential in ensuring the longevity and reliability of the motor by mitigating risks associated with running conditions that may exceed the motor's rated capacity.

While fuses can also provide protection by blowing when excessive current is reached, they are more of a one-time use solution and do not allow for reset without replacement. Relays and contactors, on the other hand, are primarily involved in controlling the operation of the motor circuit rather than direct protection against overload conditions. Therefore, the overload relay is the most suitable component for the specified purpose.