Why might a motor be equipped with a thermal protection device?

A motor is equipped with a thermal protection device primarily to prevent overheating of its windings. Overheating in electric motors can lead to insulation breakdown, which can cause severe damage to the motor and ultimately lead to failure. Thermal protection devices monitor the temperature of the motor; when a specified temperature threshold is exceeded, the device can interrupt the power supply to the motor or trigger an alarm, allowing the issue to be addressed before damage occurs.

This proactive measure is critical for extending the motor's lifespan and ensuring safe operation. In contrast to the other options, which relate to different operational aspects of motor performance, thermal protection devices specifically target the need to manage and maintain appropriate operating temperatures, thereby directly addressing the risk of overheating.