What is the minimum size for a grounding electrode conductor for a separate building based on?

The minimum size for a grounding electrode conductor for a separate building is determined by the size of the largest ungrounded conductor of the feeder. This requirement is based on the need to ensure that the grounding system can handle potential fault currents without risking damage to the grounding system or creating unsafe conditions. The connection between the size of the grounding electrode conductor and the largest ungrounded feeder conductor ensures that there is sufficient capacity to safely conduct fault currents, enhancing the overall safety of the electrical system.

This approach helps to maintain the effectiveness of the grounding system and avoids electrical hazards that might arise from inadequate grounding. It ensures that the capacity of the grounding conductor is not only suitable for the building's electrical load but also for potential fault conditions that could occur within that system. Building size, the grounding electrode's characteristics, and location are not the primary factors in determining the minimum size of the grounding electrode conductor; rather, the focus is on the feeder's ungrounded conductors, which play a critical role in the safe operation of the overall electrical system.