A Controller for Virtually Any DC Charging Source The C Series, including the C35, C40 and C60, is the benchmark of our charge controller lineup. The C35 and C60 are field configurable for 12 and 24 VDC operation. The C40 may be configured for 12, 24, or 48 VDC operation. All can be used as a charge, diversion, or load controller and come with a standard multi-color charge status LED. All three of these fully solid state, microprocessor-driven controllers are UL and cUL listed. Whatever the charging source, a C Series controller is sure to meet your DC controller needs.