What typically protects a motor from heat issues?

The thermal overload relay is specifically designed to protect motors from heat-related issues. It monitors the temperature of the motor or the current drawn by the motor and will interrupt the circuit if it detects an excessive temperature rise that can lead to overheating. This type of protection is crucial because overheating can damage the motor windings, bearings, and other components, leading to costly repairs or complete motor failure.

Unlike a circuit breaker, which primarily protects against overcurrent conditions and can reset automatically, a thermal overload relay is more focused on the thermal aspect of motor protection. While electrical fuses do serve to disconnect the power under fault conditions, they do not provide real-time monitoring of temperature or current to prevent overheating. A manual switch, on the other hand, simply allows users to turn the motor on or off but does not provide any protective functions related to thermal issues. Thus, the thermal overload relay is the most suitable device for protecting a motor specifically from heat-related failures.