What is the significance of using a DC combiner with fuses?

The significance of using a DC combiner with fuses lies primarily in its role in protecting individual source circuits. A DC combiner box consolidates the outputs of multiple photovoltaic (PV) strings into a single output, which can then be routed to an inverter. The inclusion of fuses within the combiner box adds an essential layer of safety.

If a fault occurs—such as a short circuit or overload in one of the circuits—the fuse corresponding to that particular circuit will blow, disconnecting it from the system. This prevents damage to the components in the affected string and helps maintain the overall integrity and performance of the solar power system. By providing this protection, fuses play a crucial role in ensuring the longevity of the system and safeguarding against potential fire hazards or equipment damage.

The other options do not accurately represent the primary function of a DC combiner with fuses. Combining DC into AC power occurs within the inverter stage, not at the combiner. While system design may ideally lead to lower installation costs indirectly, this is not the primary purpose of using a combiner with fuses. Additionally, increasing voltage levels is typically a function of larger system design and configurations, rather than the specific role of the combiner itself.