According to Section 690.31, how must PV systems be marked?

Marking photovoltaic (PV) systems in accordance with Section 690.31 of the National Electrical Code is essential for ensuring safety and promoting understanding of the system’s integration. The requirement for marking to indicate that the system is interconnected to a utility is critical for several reasons.

First, it informs emergency responders, technicians, and other personnel that the system can operate in conjunction with the utility grid. This is particularly important in emergencies, as it affects the safety protocols that responders must observe when working near the system. If they are unaware of a connection to the utility, they may inadvertently put themselves at risk during a power outage or maintenance activity.

Furthermore, indicating interconnection helps in compliance with local regulations and utility requirements, which often mandate such markings for ensuring the safety and integrity of both the PV system and the utility grid. It also aids in providing clarity about the system's operational characteristics, including the possibility of back-feeding electricity into the utility grid.

In contrast, the other options do not provide essential safety or operational information required for PV system marking. While details like the year of installation, the solar panel brand, or warranty periods are useful for consumers and installers, they do not communicate critical safety information regarding the system's connection status with the utility. Thus