What does the size of the grounding conductor depend on?

The size of the grounding conductor is primarily determined by the size of the service entrance conductors. This is because the grounding conductor must be adequately sized to handle potential fault currents that could occur during an electrical fault. The National Electrical Code (NEC) outlines specific requirements that dictate the grounding conductor size based on the largest ungrounded conductor in the service entrance.

For example, if larger conductors are used for the service entrance to handle increased loads, the grounding conductor must also be larger to ensure it can carry any fault current safely to ground without overheating or causing a safety hazard. This is crucial for the overall safety and effectiveness of the grounding system in protecting people and equipment from electrical faults.

The other choices do not hold the same relevance regarding the sizing of the grounding conductor. While the type of conduit, length of the wire run, and height of installation may influence installation techniques, they do not determine the required size of the grounding conductor itself according to electrical codes and safety guidelines.