To prevent the damage of whole system or battery bank, a solar charge controller plays a crucial role. It ensures, the battery doesn't get overcharged with the continuous energy flow from the solar or the grid. It stands in-between the energy generation source, the solar panels, the energy storage component (battery) and the final load.
Basic things which should be considered for Solar Charge Controller:
Battery voltage and type:
The first thing to check whether the solar charge controller can charge the battery properly or not. It's also very much important to check whether the charger is compatible with nominal battery voltage or not. Usually the common or commercial standard battery bank nominal voltages are 12, 24 or 48 volts.
PV array to feed the charger:
The solar array is the heart of the off-grid solar panel controller, so it has to be interacted with the controller. To make sure, the power and current capacity of the array can't exceed the maximum input rating of the controller.
Sizing a solar array for solar charge controller:
Sizing a solar array for a charge controller depends on three things.
Open Circuit Voltage (Voc): This is the maximum operating voltage generated by the solar array while the load is disconnected with the array. This voltage should never surpass the maximum input voltage of the controller under any situation.
Maximum-Operating Voltage (Vmp): This is the operating voltage for the PV arrays at which panels generate most wattage. It is recommended for the Vmp to be 12 or 24 volts higher than the nominal voltage of the battery.
Maximum PV array power/ current: Many controllers do not specify the maximum rated power, but by sizing the PV array according to voltage and maximum input current constraints you can guarantee that the controller can handle your panels output power. Many high-end controllers, such as the MPPT ones, offer an extra PV array power recommendation because they can handle much higher Vmp voltages than the nominal voltage of the battery connected to them thanks to the step-down capability. Thus, the number of solar panels that can you connect to your controller depends on your array open-circuit and operating voltages, and the maximum operating current.
Difference between PWM and MPPT solar charge controller:
Understand the Solar Charge Controller ratings:
To indicate or select the charge controller different application, one needs to understand the datasheet of the controllers. Based on the different parameters or ratings, these ratings can be optimized. Some of the important ratings which needs to be understand clearly:
Nominal Battery System Voltage: Generally it indicates the battery bank voltage of the system which can be compatible with 12V/24V/36V or 60V. Some battery banks can be designed with more larger system voltages, but these are usually applicable for industrial applications.
Maximum Continuous Output Current: Related to the maximum current that the device can provide to charge the battery bank.
Maximum input current: This definitely should be the lower than the input limit of the charge controller, which is associated with the maximum solar panel array output during short-circuit condition.
Operating input voltage: The value of the voltages may vary according to the temperature. So, the controller can work properly, array voltage variations must be located within the pre-established limits of the controller.
Maximum PV System Voltage: Maximum voltage under coldest conditions that are allowed on the PV array.
Maximum Array STC Nameplate: Maximum STC power permissible in the PV system.
EverExceed has more than a decade of experience in solar industry. Based on the vast knowledge, EverExceed select the best, high quality, high reliability product to manufacture Solar Charge Controller. Also with the expertise, the quality after-sale service of EverExceed can make you stress free. Based on different industry and requirement, EverExceed provide Solar Charge Controller for different applications. If you want to know more about EverExceed Solar Charge Controller contact EverExceed today. Our team is experienced enough to provide you best solution for your needs.
