PWM

PWM (Pulse Width Modulation) controllers are the basic type of solar controllers that control battery charging using pulse width modulation. They adjust the current supplied by the solar panels so that the battery is not overcharged and is properly maintained.

How PWM controllers work:

• Controls charging current by switching the flow of energy on and off in rapid pulses

• Keeps the battery in optimal charging mode to prevent overcharging

• They regulate charging in phases – charging, maintenance, or equalization

Advantages of PWM controllers:

• Affordability and simplicity

• Reliable battery overcharge protection

• Easy to install and operate

• Suitable for small and medium solar systems

Limitations of PWM controllers:

• Lower efficiency compared to more modern MPPT controllers, especially at lower irradiance or higher panel voltage

• Less flexible in adjusting panel output