HOLT Electricians Practice Exam

What does the NEC require regarding the protection of motors and associated control apparatus?

1. Only short-circuit protection is needed

2. Only overload protection is necessary

3. Both overload and short-circuit protection are required

4. No protection is required

The correct answer is: Both overload and short-circuit protection are required

The National Electrical Code (NEC) mandates that motors and their associated control apparatus must have both overload and short-circuit protection to ensure safe operation and prevent potential hazards. Overload protection is essential because it guards against excessive current that can cause overheating of the motor windings, leading to deterioration and possibly complete motor failure. Short-circuit protection is equally critical, as it prevents damage and fire risks caused by sudden, unexpected increases in current that can occur during faults. By requiring both types of protection, the NEC aims to enhance the safety and reliability of motor installations. This dual protection strategy minimizes the risk of electrical fires, equipment damage, and safety hazards in the workplace. Therefore, the requirement for both overload and short-circuit protection is a comprehensive approach to safeguarding electrical systems.