Heating, Ventilation, and Air Conditioning (HVAC ) Electrical Practice Test

What happens to a motor if an overload occurs during operation?

1. It speeds up

2. It shuts down

3. It continues running

4. It consumes more energy

The correct answer is: It shuts down

When an overload occurs during the operation of a motor, it typically results in the motor overheating due to excessive current draw. To protect itself from damage caused by this condition, the motor is designed to shut down or trip. This automatic shutdown mechanism is critical for preventing further issues such as insulation failure, burnout, or physical damage to the motor components. In systems equipped with overload protection devices, these devices detect when the current exceeds a predetermined level for a specific duration and then interrupt the power supply to the motor, thereby preventing catastrophic failure. After the overload condition is rectified, the motor can be reset and restarted, which helps in maintaining the longevity and reliability of the equipment. This protective feature ensures that while the motor is working hard to perform its intended function, it also has safeguards in place to avoid serious damage that could occur during an overload situation.