M20A solar controller applied to the solar photovoltaic system which is used to coordinate solar panels, storage battery and load. It is a very important assembly in the photovoltaic system. It is different from other solar controllers that it is add the comprehensive protection function makes the whole solar photovoltaic system operate efficiently and safely. M20A solar controller can adjust automatically the working voltage of solar panels, which can make solar panels work consistently in the maximum power point of the V-A characteristic curve in a whole day. Compared with common solar controllers, it is equipped with temperature compensation function, can make the work efficiency of photovoltaic modules increased by 30%, and can observably prolong the life of the storage battery. Features: LCD screen display MPPT+ PWM charging mode Simple (and more time control) operation A key to restore the factory settings Parameter user can reset A key to open and close the load Automatic temperature compensation function Battery under voltage protection Overload, short-circuit protection Battery reverse discharge protection Battery reverse polarity protection USB5V charge (current 500mA) Optional Specification: Model: MPTT-M20 Maximum Power Current: 20A Peak power of solar cell panel (Max Wp): ≤260W Battery capacity configuration: ≥200AH Temperature Compensation: -4mV / Cell / ℃ Maximum open circuit voltage of the solar panel: 18V-24V(12V system) 36V-48V(24V system) Package List: 1 x Solar Charge Controller 1 x User Manual