In a building with a metal underground water pipe electrode, how must grounding electrodes be used for a separately derived system?

In a scenario involving a separately derived system with a building that has a metal underground water pipe electrode, it is essential to use both electrodes for grounding. This is due to the need for redundancy and safety in the grounding system. Utilizing both electrodes—like the metal underground water pipe and any additional grounding electrode—ensures that there is an effective path to ground. This helps to protect both the electrical system and any equipment connected to it from faults or surges that may cause hazardous conditions.

The regulations often specify that additional grounding electrodes are not just optional but necessary when using a separately derived system, as it enhances the overall grounding system’s effectiveness. Following these guidelines minimizes the risk of ground potential rise and enhances personal safety and equipment security.

In contrast, relying solely on one electrode or not meeting the requirement for grounding adequately could create potential hazards. Thus, using both electrodes fulfills the code requirements and enhances the safety of the system.