Functional characteristics:1.Due to an advanced digital power technology, the circuit energy conversion efficiency is as high as 98%. 2.It provides an active charging voltage regulation feature. At battery open circuit or lithium battery overcharge protection, the controller battery terminal will output the rated charging voltage value. 3.Available in multiple battery types and support charging procedures of types of batteries such as lithium battery, battery, sealed battery, vented battery, lithium battery, etc. 4.A current-limited charging mode is available. When the power of solar panel is too large and the charging current is higher than the rated valve, the controller automatically reduces the charging power so that the solar panel can operate at the rated charging current. 5.Support automatic identification of lead-acid battery voltage. External LCD screen or Bluetooth module can be connected for viewing of equipment operating data and status, and modification of controller parameters is supported. 6.Support standard Modbus protocol to meet communication needs in different occasions. 7.Built-in over-temperature protection mechanism. 8.Temperature compensation and automatic adjustment of charge and discharge parameters help to improve battery life. 9.Solar panel short circuit protection, battery open circuit protection and lightening protection etc. Protection: Waterproofing protection: Rating: IP32. Input power limited protection: When the power of solar panel is higher than the rated value, the controller will limit the power of solar panel within the rated power range to prevent damage by over current, and the controller enter the current-limiting charge. Battery reverse polarity protection: If the battery polarity is reversed, the system will not work but it will not burn out the controller. PV input end voltage is too high: If the voltage at the PV array input end is too high, the controller will automatically shut off the PV input. PV input end short circuit protection: If the voltage at the PV array input end is short circuited, the controller will turn off charging; after short circuit is removed, charging will automatically recover. Introduction: MPPT technology,enables maximum energy tracking for solar panel and llows the controller to quickly and accurately track the maximum power point of PV array in any environment. This product can be connected to an external LCD screen or Bluetooth communication module and PC Upper Computer for dynamic display of operating status, operating parameters, controller logs, control parameters, etc. Adopting standard Modbus communication protocol and providing overall electronic fault self-test and powerful electronic protection functions which minimize components damage due to installation error and system failure. PV input reverse polarity protection: When the polarity of PV array is reversed, the controller will not be damaged, and normal operation will continue after wiring error is corrected. Night reverse charging protection: Prevent battery discharge through the solar panel at night. -protection Over-temperature protection: When temperature of the controller exceeds the set value, it will reduce charging power or stop charging. System voltage 12V/24V Battery voltage 9V~32V material: plastic Color as shown Maximum power point voltage range (Battery voltage +2V) - 72V Package Contents: 1 x MPPT Solar Charge Controller(20A) 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.