SHURflo DC Pump Controller, Model# 902-100 Maximum input voltage: 45 Volt DC (Open Circuit)(Two Panels 12 Volt nom. In series max.) Startup voltage: 25.0 Volts +/-2%, two modules 17.5 Volts mpp in series Output voltage limiting: 28 Volts Max. output current: 5 Amps Power consumption: 25mA