With the advanced dual- or multi- tracking technology, when the solar panel is shadowed or part of the panel fails resulting in multiple peaks on the I-V , the controller is still to accurately the maximum power point. A built-in maximum power point tracking algorithm can significantly the energy utilization efficiency of photovoltaic , and raise the charging efficiency by 15% to 20% compared with the conventional PWM . A combination of multiple tracking algorithms enables accurate tracking of the optimum working point on the I-V in an extremely short time. The product boasts an optimum MPPT tracking efficiency of up to 99.9%. Advanced digital power supply technologies raise the circuit's energy conversion efficiency to as high as 98%. Charging are available for different types of batteries including gel batteries, sealed batteries, open batteries, lithium batteries, etc. The controller features a limited current charging mode. When the solar panel power exceeds a certain level and the charging current is larger than the rated current, the controller will automatically lower the charging power and bring the charging current to the rated level. Instantaneous current startup of capacitive loads is supported. Automatic recognition of battery voltage is supported. LED fault indicators and an LCD screen which can display abnormality information help users to quickly identify system faults. Historical data storage function is available, and data can be stored for up to a year. The controller is equipped with an LCD screen with which users can not only check device operating data and statuses, also controller parameters. The controller supports standard Modbus protocol, fulfilling the communication needs of various occasions. The controller employs a built-in over-temperature protection mechanism. When temperature surpasses the set value, the charging current will decline in linear proportion to the temperature so as to curb the temperature rise of the controller, effectively keeping the controller from being damaged by overheat. Featuring a temperature compensation function, the controller can automatically adjust charging and discharging parameters in order to extend the battery's service life. This product can keep monitoring the solar panel's generating power and tracking the highest voltage and current values (VI) in real time, enabling the system to charge the battery in maximum power. It's designed to be used in off-grid solar photovoltaic to coordinate operation of the solar panel, battery and load, functioning as the core control unit in off-grid photovoltaic . This product features an LCD screen which can dynamically display the operating status, operating parameters, controller logs, control parameters, etc. Users can conveniently check parameters by the keys The controller utilizes standard Modbus communication protocol, making it easy for users to check and system parameters on their own. Besides, by providing free monitoring software, we give users the maximum to satisfy their needs for remote monitoring. With comprehensive electronic fault self-detecting functions and powerful electronic protection functions built inside the controller, damage caused by installation errors or system failures can be avoided to the greatest extent possible. : plastic + metal Color as shown Package Contents: 1 x MPPT 20A Solar Charge Controller 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 a little different from the real thing. The measurement allowed error is +/- 1-3cm.