Exposed noncurrent-carrying metal parts of PV systems must be connected to what?

Exposed noncurrent-carrying metal parts of photovoltaic (PV) systems must be connected to an equipment grounding conductor to ensure safety. The purpose of connecting these metal parts to an equipment grounding conductor is to mitigate the risk of electric shock by providing a low-resistance path for fault current. In the event of a fault, the grounding conductor will facilitate the operation of overcurrent protection devices, helping to clear the fault quickly and reduce the chance of a person encountering hazardous voltage.

This requirement is crucial because it provides a safety mechanism to protect individuals and reduces the chance of electrical fire hazards. The National Electrical Code emphasizes the importance of grounding in electrical installations, especially in systems that may involve outdoor or exposed components like PV systems.

Options such as an ungrounded conductor, a neutral conductor, or an isolation switch would not serve the same safety purpose as an equipment grounding conductor. An ungrounded conductor could lead to unsafe voltages in the event of a fault, while a neutral conductor is meant to carry current under normal operating conditions and does not serve the same protective function. An isolation switch is used for disconnecting power and does not inherently provide grounding protection for exposed metal parts.