This is a step-down controller, taking into account the voltage drop of the photovoltaic panel wire and the low voltage of the photovoltaic panel on , the open circuit voltage of the photovoltaic panel must be higher than 18V input, and the photovoltaic panel of 18V is 2 in series: for example, 18V-72V is with 12V, and 42V-80V is with 24V. Specifications: Input voltage 18V-90V Output 2V-60V Output current 0-25A Adjustable output current limiting short-circuit protection Standby power consumption 0.9W during the day, automatic anti-reflux power consumption 0 at night No activation rechargeable carp battery unattended automatic charging. can also be , no electricity automatic charge automatic stop Support adaptive 5W-800W photovoltaic panel Automatic temperature control fan heat dissipation Support DC-DC regulated power supply output can directly with heating tube and other loads The output comes with the ideal diode function of high current, which can be directly to the battery without the need to connect the diode Can be used as a buck voltage regulator adjustable power supply Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.