Solar charge controller is a device that acts as the interface between solar PV modules and batteries. A solar charge controller is needed in virtually all solar power systems that utilize batteries.  


  • Limits the rate at which current is added to batteries. If batteries are charged at rates higher than their recommended rates, it reduces battery life.

  • Prevents the battery from over-charging, which reduces battery life drastically. Over-charging or charging abusively can also lead to emission of gases; both in the case of FLA batteries as well as VRLA batteries (value-regulated lead-acid battery).VRLA batteries are also called Sealed Lead –Acid battery or maintenance free battery.

  •  Limits the rate at which current is drawn from the batteries. If batteries are discharged at rates higher than their recommended rates, it reduces battery life.

  •  Prevents the battery from over-discharging, which reduces battery life drastically, especially if the batteries are not designed to handle deep discharge conditions. Overcharging or charging abusively can also lead to emission of gases, both in the case of FLA batteries as well as VRLA batteries.

  • Essentially, a solar charge controller does the job of increasing the life of batteries to the extent possible.


The two types of solar charge controllers are:

     1) PWM (Pulse Width Modulation)

     2)MPPT(Maximum power point tracking)


A PWM solar charge controller uses pulse width modulation to slowly lower the amount of power added to the batteries as they get closer to getting fully charged. This technique allows the battery to be more fully charged, while putting minimal stress on the battery. Therefore, the battery life is extended quite a bit.

A PWM solar charge controller can also keep the battery in a fully charged state (called “float”) indefinitely.


An MPPT solar charge controller is more advanced compared to a PWM solar charge controller. So it does everything that a PWM solar charge controller does. Additionally, the most important thing that it does is extract maximum power from the solar PV modules, which is why it gets its name.


Also, see our other products like Solar Pump Controller and Solar Water Level Controller.