Which section of the NEC covers ampacities of equipment grounding conductors?

The correct choice relates to Section 250.122 of the National Electrical Code (NEC), which specifically addresses the ampacity of equipment grounding conductors. This section outlines the requirements and calculations necessary to determine the appropriate size of grounding conductors based on the size of the overcurrent protective device being used, ensuring proper operation and safety in the electrical system.

Understanding this section is crucial because grounding conductors serve an essential role in protecting systems and individuals from electrical faults. By specifying the appropriate ampacity, the NEC ensures that these conductors can safely handle any fault currents without overheating or failing.

The other sections mentioned focus on different aspects of electrical installations. For instance, Section 250.123 deals with the general requirements for grounding conductors, Section 230.67 addresses the requirements for service equipment, and Section 210.6 governs branch circuits. Each has its specific focus, but none cover the ampacities of equipment grounding conductors like 250.122 does.