Single-pole grounding of photovoltaic panels

Does a photovoltaic system have a DC grounding system?

Photovoltaic systems having dc circuits and ac circuits with no direct connection between the dc grounded conductor and ac grounded conductor shall have a dc grounding system. The dc grounding system shall be bonded to the ac grounding system by one of the methods in (1), (2), or (3).

Why is proper grounding of a photovoltaic power system important?

Proper grounding of a photovoltaic (PV) power system is critical to ensuring the safety of the public during the installation’s decades-long life. Although all components of a PV system may not be fully functional for this period of time, the basic PV module can produce potentially dangerous currents and voltages for the life of the system.

Do I need a grounding electrode for a PV array?

While a separate grounding electrode system is still permitted to be installed for a PV array, per 690.47 (B), it is no longer required to be bonded to the premises grounding electrode system. In PV systems with string inverters, the equipment grounding conductor from the array terminates to the inverter’s grounding bus bar.

What is a grounding point of a PV inverter?

The grounding point of the inverter is connected onwards to the grounding system or grounding electrode of the residential facility or building (see figure below). 15) PV circuits having 30V or 8A more shall be provided with a ground-fault protection device (GFPD). Nowadays, in general, this is a built-in function of inverters.

What is a solidly grounded PV array?

A solidly grounded PV array, as permitted, in 690.41 (B), as permitted, per 690.41 (A) (5), is a special case where the PV array contains no more than two source circuits, i.e., two strings of modules, the PV system circuitry is not located in or on a building, and the system is solidly grounded.

Can ungrounded PV systems be used with isolated inverters?

Most PV systems in the United States use isolated inverters with internal transformers (isolated inverters in the ROW) as of 2012, but non-isolated inverters and ungrounded PV systems are being certified/listed and are making market inroads. Note that ungrounded arrays can also be used with isolated inverters.