What is the requirement for the parallel wiring of PV source circuits?

The requirement for the parallel wiring of photovoltaic (PV) source circuits is that there must be equal voltage and current sharing among the circuits. This ensures that each parallel-connected source circuit contributes effectively to the overall output without overloading any single circuit. When multiple circuits are connected in parallel, they should ideally operate at the same voltage to prevent imbalances that could lead to inefficiencies or safety hazards.

If the voltages differ among the circuits, it could result in one circuit taking on more current than others, potentially causing damage to the components or system. This principle is crucial to ensure the longevity and effectiveness of the PV system, as well as compliance with the National Electrical Code (NEC) requirements for safe electrical installations.

The other choices do not align with NEC guidelines for parallel wiring. Connecting all circuits in series, for instance, would not allow for the sharing of current in the same manner, as series circuits would sum voltages instead of facilitating equal sharing of both voltage and current. Additionally, requirements regarding underground burial of wiring and limiting operation to just one circuit at a time are not relevant to the principles of connecting PV source circuits in parallel.