What occurs within a DC combiner in a photovoltaic system?

The function of a DC combiner in a photovoltaic system is to take multiple PV source circuits and combine them into a single output circuit. This process allows for easier management and connection of several parallel strings of solar panels, enabling them to feed their combined DC electricity into the inverter or directly into the electrical system.

By utilizing a combiner box, the system simplifies wiring and minimizes the number of connections needed. This is particularly useful in larger installations, where multiple strings of solar panels might otherwise require complex individual connections to the inverter, increasing the risk of issues such as loose connections or increased installation difficulty.

The other options reflect different concepts in photovoltaic systems that do not accurately describe the primary function of a DC combiner. For instance, increasing voltage for long-distance transmission relates more to transformer operation, while grounding pertains to electrical safety practices and is not the primary role of the combiner. The specification of only using string inverters does not capture the diverse configurations that might be present, as DC combiners can work with various inverter types.