Designed to manage solar and alternator power inputs to charge an auxiliary (house) battery system. The system will preference solar, providing lower loads on your engine when solar is available. With automatic ignition detection enabled, the system will isolate the starting battery when the engine is off, preventing discharge of your critical starting battery. Its fully automatic, with a set-and-forget type operation. The microprocessor controlled circuit keeps your battery in peak condition, automatically switching between six charging modes; Qualification, Recondition, Bulk, Absorption, Check, and Maintenance. Housed in a heavy-duty aluminium case with mounting bracket, and a front panel with charge status LEDs and push button to select between Lead acid, AGM, Calcium, GEL or LiFePO4 batteries. It handles solar panels with 16 to 25V open circuit voltage, and includes over charge, short circuit, over temperature, reverse polarity, thermal overload, and solar input overload safety protection. Features: - Dual input - solar and/or alternator/car battery - 20A max charging current (automatically controlled) - Six-stage Battery Charging - Supports Lead acid, AGM, Calcium, GEL or LiFePO4 batteries Specifications: Solar Panel Open Circuit Voltage: 16~25V max. Rated Output Power: 13.5~15.4V @ 20A Output (Charge) Voltage: AGM/GEL: 14.3V (Boost), 14.7V (Absorption), 13.5V (Float) Lead acid: 14.0V (Boost), 14.4V (Absorption), 13.5V (Float) Calcium: 15.0V (Boost), 15.4V (Absorption), 13.5V (Float) LiFePO4: 14.0V (Boost), 14.4V (Absorption)