The solar charge controllers main function is to regulate both voltage and current passing from the solar panel to the battery to protect it from being over charged and damaged . This is essential for any practical solar system. Since the charging current passing from solar panel to battery vary during the time of the day due to clouds, shade, sunshine, the charging current will vary and may overcharge the battery. Simply, it will stop charging the battery when overcharged and start charging it back when the voltage drops back to healthy level.
This solar charge controller is rated at 20 A and 12/24 V. It uses the PWM control for regulating the battery current and voltage which allow for smooth transition and longer battery life. It used microprocessor for control calculations. It has led indicators for solar panel, battery and load status. It also have 2 digit display. In addition it features automatic voltage selection and temperature compensation.
How to select the solar charge controller
Let us explain by simple example, let assume that we have 12 V solar panel system which include two module. Each module is rated 7 A, the two modules will produce 14A. Add 25% safety margin it will be 17.5. The charge controller should be rated at 17.5A or higher. 20A will be good this example.
- Automatic voltage detection
- Over charging and discharging protection
- Overload protection
- Short circuit protection
- Reverse current protection
- Temperature compensation
- PWM control
- Status indicators of solar panel, battery and load
- Digital LCD display