When using a metal water pipe as the grounding electrode for a separately-derived system, where must the grounding electrode conductor be connected?

When using a metal water pipe as the grounding electrode for a separately-derived system, the grounding electrode conductor must be connected 5 feet or closer to the point where the pipe enters the building. This requirement is in place to ensure an effective grounding connection that minimizes the length of the grounding path, thereby reducing the impedance and improving the overall safety and reliability of the grounding system. Connecting the conductor in this manner helps ensure that if there is a fault condition, the ground potential rise will be minimized, thus providing better protection against electrical shock hazards.

This connection point is critical because the grounding electrode system should be as close to the entry point as possible to avoid the potential for electrical surges traveling long distances through the building's plumbing system. Grounding systems designed according to code reduce the risk of voltage differences that can occur in a fault situation, thus enhancing safety for electrical installations within the building.