This prewired Solar PV Combiner Box ensures easy and safe integration into your solar power system. With a 4 input, 4 output configuration and DC 1000V rating, it provides reliable protection with IP65-rated weatherproof housing. Available in the following variations:What it is: A solar combiner box (also called a PV combiner box or DC combiner box) is an electrical enclosure that collects DC output from multiple solar panel strings, combines them onto a common busbar, and routes the combined power to the inverter — while providing overcurrent protection, surge. A PV combiner box is an electrical enclosure that brings multiple solar string circuits together before the inverter or charge controller. In a typical solar PV system, each string produces DC power.