HOLT Electricians Practice Exam

What must the standard size overload protection device be sized according to?

1. Manufacturer's guidelines

2. Section 430-32 of the NEC

3. Local electrical codes

4. Motor's voltage rating

The correct answer is: Section 430-32 of the NEC

The standard size of an overload protection device should be sized according to Section 430-32 of the National Electrical Code (NEC). This section provides specific guidelines for determining the appropriate size and rating of overload devices for motors, ensuring they provide adequate protection without being too sensitive or too lax. Section 430-32 outlines factors such as the full-load current of the motor, which is critical for sizing the device correctly. It ensures that the overload protection will trip in case of an overcurrent situation, which can prevent damage to the motor from overheating or excessive current draw. By adhering to these standards, electricians can ensure compliance with national safety regulations while also optimizing the performance and lifespan of the motor. While manufacturer guidelines and local electrical codes are important considerations, they must not contradict the specific sizing requirements established in the NEC to ensure proper safety and functionality. The motor's voltage rating, while important for other aspects of design and installation, does not directly determine the size of the overload protection device as outlined in the NEC.