A PV combiner box, also known as a solar array combiner box or a string combiner box, is an electrical component that is typically used in a photovoltaic (PV) system. The combiner box collects the electrical currents from multiple strings of solar panels and combines them into a single output. The combiner box is generally located near the solar panels and contains fuses or circuit breakers to protect against overcurrents and short circuits. It is also often equipped with surge protection devices to safeguard against lightning strikes and other electrical surges. The number of strings and the size of the combiner box depends on the size of the PV system and the number of solar panels in the array.