Is it true that the equipment grounding conductor for PV output or source circuits can be no smaller than 10 AWG copper?

The statement is false because the size of the equipment grounding conductor (EGC) for photovoltaic (PV) output or source circuits is determined by various factors including the size of the circuit conductors, the system capacity, and the relevant electrical codes. Specifically, the National Electrical Code (NEC) offers guidelines that help in determining the correct size of the equipment grounding conductor based on the largest ungrounded conductors in the circuit.

For example, under NEC guidelines, the grounding conductor must be sized appropriately in relation to the largest conductor size used in the PV system. If the circuit conductors are larger, a larger EGC is required. Conversely, if the conductors are smaller, an EGC that is 10 AWG may not be necessary and could potentially be oversized for specific applications.

The importance of this flexibility in sizing ensures both safety and compliance with regulations. Thus, the statement regarding the minimum size being 10 AWG is not universally applicable, making the assertion that it is true incorrect.