What must be established for the grounding of a PV system according to Article 690?

Establishing a grounding electrode system is essential for the safe operation of a photovoltaic (PV) system. According to Article 690 of the National Electrical Code (NEC), a grounding electrode system is necessary to connect the electrical system to the earth, thereby providing a path for fault currents and helping to prevent electrical shock hazards.

The grounding electrode system serves multiple purposes, including stabilizing voltage levels during normal operation and offering a pathway for fault currents in the event of an equipment failure. This is critical in maintaining the integrity of the PV system and ensuring safety for both the system components and personnel who may work on or near the system.

While other options might imply alternative grounding methods, they do not satisfy the NEC requirements for PV systems. For instance, a temporary grounding system is not practical for permanent installations and does not provide ongoing safety. Similarly, having only a circuit ground lacks the comprehensiveness necessary for the overall safety measures established by the NEC. The suggestion that no grounding is required contradicts the fundamental principles of electrical safety and the guidelines set forth in the code. Therefore, the grounding electrode system is mandated as a crucial element of PV system installations to ensure reliability and safety.