In PV systems, what does the grounding electrode system connect to?

In photovoltaic (PV) systems, the grounding electrode system is essential for ensuring safety and compliance with the National Electrical Code (NEC). The grounding electrode system connects to the building's electrical services to establish a common ground reference. It helps protect the system from lightning strikes, over-voltages, and electrical faults by safely directing any faults to the ground, thereby minimizing the risk of electrical shock or fire.

By connecting the grounding electrode system to the building's electrical services, it ensures that all electrical components within the system, including the inverter and other equipment, are at the same electrical potential as the building's grounding system. This integration prevents differences in voltage between the solar equipment and the existing electrical system, reducing the risk of damage and ensuring reliable operation of the PV system.

The other options do not align with the purpose of the grounding electrode system. Connecting directly to solar panels or utility lines does not provide the necessary safety measures outlined in the NEC. Connecting to equipment generating excess electricity would not create a secure grounding path, risking potential hazards. Thus, grounding the PV system through the building's electrical services is critical for effective safety and operation.