DC Combiner Boxes for photovoltaic systems The DC Combiner Box collects and distributes the string currents from the solar panels. to a single outpu ance cables by combining strings at the array locat ciency, reliability and safety in solar energy systems. They enable centralized management in large-scale and remote installation ity), equipment aging, and poor installation practices. Specialists who design and. Our DC combiner boxes offer users the possibility to integrate short-circuit and overvoltage protection, as well string monitoring solutions (I,V, T and SPD and switch isolator status), for PV systems using central inverters with PV panels in trackers and fix tilt systems.