Feature: 1. For Off Grid System: The controller is designed for off grid solar photovoltaic system, used to coordinate the operation of solar panels, batteries and loads. 2. High Efficiency: Built in MPPT algorithm, the tracking efficiency is up to 99.9%, and energy conversion efficiency is improved to 98%, the charging efficiency is improved by 15% to 20% compared with PWM method. 3. Widely Compatible: Can provide charging options for different types of batteries, including gel batteries, sealed batteries, elastic batteries, lithium batteries, etc. 4. Limited Current Charging: When the power exceeds a certain level and charging current is greater than rated current, the controller will automatically reduce charging power to make charging current achieve rated value. 5. LCD Display: LCD screen can dynamically display the operation status, operation parameters, controller log, control parameters, etc. 6. Easy Operation: Adopt standard communication protocol, users can easily check and modify system parameters. Free monitoring software is provided to meet users' needs for remote monitoring. 7. Powerful Protection: With comprehensive electronic fault self detection function, built in powerful electronic protection function, avoid component damage caused by installation error or system fault. Specification: Item Type: MPPT Solar Charge Controller Material: Aluminum Alloy, PC Battery Voltage: 12V 24V (Automatic) No Load Loss: 0.7-1.2W Battery Voltage: 9-35V Rated Charging Current: 40A Rated Discharge Current: 20A Photovoltaic System Maximum Power: 550W (12V), 1100W (24V) Communication Mode: RS232 RS485 Solar Panel Maximum Voltage: 100V (25), 90V (-25) Altitude: 3000m. Package List: 1 x MPPT Solar Charge Controller1 x Temperature Sensor1 x English Manual