Which NEC table is used to determine the minimum size equipment grounding conductor for a generator supplying a separate building?

The minimum size equipment grounding conductor for a generator supplying a separate building is determined using Table 250.122. This table specifically provides the sizing requirements for equipment grounding conductors based on the rating of the overcurrent device protecting the branch circuit or feeder.

In the case of a generator that supplies power to a separate building, selecting the appropriate size for the equipment grounding conductor is essential for ensuring safety and compliance with the National Electrical Code (NEC). This table considers the different configurations and applications where grounding conductors are necessary, allowing electricians to choose the correct size based on the ampacity of the connected equipment and circuits.

Choosing this table ensures that the grounding system is adequate to safely handle fault currents and provides a reliable path for those currents to earth, thus enhancing the overall safety of the electrical installation.