Mastervolt SCM20 solar charge regulator 131822000 is based on Pulse Width Modulation (PWM) technology and is a great solution to charge your batteries with solar energy. The solar charge regulator is suitable for both 36 cells panels (12V) and 72 cells panels (24V). The Mastervolt SCM20 solar regulator is ideal for marine and mobile environments, due to it's protection against water spray, suitability for high ambient temperature and compatibility with negative grounding. An optional temperature sensor is available, using Part Numbers M41500500 or M41500800. The Solar ChargeMaster controller is suitable for all kinds of lead-acid batteries in 12V and 24V. The device features a large display and switchable output with evening / night lighting function. It is safe, user friendly and flexible. Battery Charger Specifications: System voltage (battery): 12/24 V auto select Nominal charge current: 20A Battery types: AGM, Gel, flooded Battery temperature sensor: optional, product code M41500500 Switchable output (max. current): 20A Energy consumption (night): <7mA Specifications solar input (DC): Panel type (12 V system): 36 cells Panel type (24 V system): 72 cells Max. PV current (Imp): 20A Recommended PV power (12V system): 360 Wp Recommended PV power (24V system): 720 Wp Mastervolt 131822000 General Specifications: Cooling: passive Display/read-out: backlit LCD with PV power, load power, battery voltage, charge current, warnings, battery state of charge, battery setting. Grounding: common negative grounding SCM20 Solar Charge Regulator Technical Specifications: Technology: PWM (Pulse Width Modulation) Protections: over temperature, over load, high/low battery voltage, high/low PV voltage, short circuit, reverse polarity & HV transients. Relative humidity: 95% non-condensing