What is the role of an overload relay in motor protection?

An overload relay plays a crucial role in motor protection by detecting and interrupting overcurrent conditions that could potentially cause damage to the motor. The primary function of this device is to monitor the current flowing through the motor and compare it to predefined settings, typically based on the motor’s rated current capacity.

When the current exceeds the preset limit for an extended period, indicating an overload situation, the relay activates and interrupts power to the motor. This action helps prevent overheating and potential burnout, which could result from prolonged periods of excessive current draw due to mechanical jams, excessive load, or other issues affecting the motor's performance.

By effectively breaking the circuit during overload conditions, the overload relay protects not only the motor but also the entire system that the motor operates within, promoting safety and longevity of the equipment.