HOLT Electricians Practice Exam

Must all motor overcurrent protection comply with NEC Article 430?

1. Yes, without exceptions

2. No, only for large motors

3. No, Article 240 is applicable

4. Yes, excluding small motors

The correct answer is: Yes, without exceptions

Motor overcurrent protection is indeed governed by the National Electrical Code (NEC) Article 430. This article provides guidelines specifically for the protection of motors, ensuring that they operate safely and efficiently under various conditions. The NEC requires that all motors, regardless of size, must have an appropriate level of overcurrent protection to prevent damage from overloads and short circuits. The reason for compliance with Article 430 is to ensure proper coordination between motor protection devices and the characteristics of the motor load. This includes aspects such as the rated current, starting currents, and locked rotor currents, which can be significantly higher than the normal operating current. This requirement means that all motors must have properly rated overcurrent protection devices, ensuring that they can handle the expected load without tripping unnecessarily while also providing adequate protection from faults. Thus, the answer indicates that there are no exceptions to this rule, enforcing the importance of consistent application of these safety standards across all motors.