The choice of the solar charge controller is determined according to the specifications of the solar energy, mainly considering two factors, one is the current of the solar panel, or the other is the voltage of the solar panel.

   One: The current of the solar panel

The size of our solar controller, such as 10A, 20A, 60A, this refers to the maximum charge and discharge current of the solar controller. The current from the solar panel cannot exceed this value, otherwise the controller will be burned out. When choosing, we generally give a reservation of 20~30%. That is, if the solar panel current is 7A, usually we should choose a 10A controller.

   Two: the voltage of the solar panel

Solar energy usually has two voltages to pay attention to, one is the working voltage, such as 18V, 36V, 72V, and the other is the short-circuit voltage. Generally, the short-circuit voltage of 18V solar panels is about 22V, and the short-circuit voltage of 36V is 42V, 72V solar panels. The short-circuit voltage is 80V. We choose the corresponding controller according to the working voltage of the solar energy. For 18V panels, choose 12V controllers, and for 36V solar panels, choose 24V controllers.

   The voltage range of PWM solar controller is usually 0~55V, and the voltage of MPPT solar controller is 0~150V. Any solar panel in this voltage range can have a suitable controller.