What occurs if a motor overload protective device is not properly rated?

If a motor overload protective device is not properly rated, it may fail to function as intended during an overload situation. Specifically, the protective device is designed to trip and shut off the motor if it draws too much current, which can happen if the motor is overloaded. However, if the device is not rated correctly for the motor's specifications, it might not recognize the overload condition due to incorrect current thresholds, allowing the motor to continue running despite the excessive load. This can lead to overheating, insulation damage, and ultimately motor failure, thus underscoring the importance of proper rating for effective protection.

In contrast, options that suggest the motor will operate at maximum efficiency or that the system will work without issues do not account for the fundamental role of protective devices in preventing damage. Additionally, the idea that the motor simply will not start at all does not accurately reflect the issues caused by improper ratings in overload protection; instead, it highlights a different aspect of motor operation.