The size of the grounding conductor is a critical factor. It needs to be large enough to carry the fault current safely to the ground. . A pv combiner box serves as the central collection point for the direct current (DC) electricity generated by groups of solar panels, known as strings. After running the 6 awg wire to the panel array for grounding it has been said to connect that 6 awg to the ground bar inside the combiner and then through conduit (along with panel array wires) and connect that 6 awg wire to the inverter ground.
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