Feature: 1. MAIN PURPOSE: Helps you automatically manage solar panel and battery operation with built in industrial microcontroller, compatible with 12V 24V system voltage. 2. DUAL USB OUTPUT: 3 levels PWM charging management with dual USB interface outputs, 5V/2.5A (maximum), which can charge mobile phones, tablets, PCs. 3. CIRCUIT PROTECTION: With overcurrent, short circuit, reverse connection, low voltage and overcharge protection, safe operation and extended battery life. 4. 3 LEVEL PWM CHARGING: Adopt fast charging, large charging and floating charging 3 phase PWM adjustment charging, to achieve efficient and intelligent charging. 5. WIDE APPLICATION: Suitable for solar power generation systems, smart homes, solar ventilation systems, solar light boxes, billboards and warning lights, etc. Specification: Item Type: Solar Charge Controller Supported Battery Type: B1: Acid battery 12V/24V (automatic identification) B2: Lithium ion battery (lithium battery) 3 strings of 3.7V=11.1V B3: LiFePO₄ battery 4 strings of 3.2V=12.8V System Voltage: 12V/24V automatic adaptation Maximum PV Voltage: Up to 23V at 12V; up to 46V at 24V Charge Cut off Voltage: 14.4V(B1) 12.6V(B2) 14.6V(B3) Discharge Cut off Voltage: 10.7V(B1) 9V(B2) 10V(B3) Discharge Recovery Voltage: 12.6V((B1) 10.5V(B2) 12V(B3) Light Control Turn on Threshold: Photovoltaic Panel 8V Light Control Turn off Threshold: Photovoltaic Panel 8V USB Output: 2 way USB output, 5V/2.5A (maximum) Standby Current: <10mA Working Temperature: -35~+60℃. Package List: 1 x Solar Charge Controller1 x English User Manual Note: No need to reset when the battery runs out, because it remembers various parameters set by the user