What is the function of an overload relay?

An overload relay serves the essential function of protecting electric motors from overheating, which can happen due to conditions such as excessive current draw. When a motor operates beyond its designed capacity, an overload relay detects this increase in current and activates a mechanism to interrupt the electrical supply to the motor. This action prevents potential damage to the motor caused by overheating, which could otherwise lead to insulation failure or motor burn-out.

This protective function is critical in maintaining the longevity and reliability of motors in various applications, ensuring they operate safely and efficiently. By interrupting the current flow during overload situations, the relay acts as a safeguard against potential catastrophic failures and unplanned downtime, which can be costly.