Charge Controllers

Charge Controllers

Charge Controllers are regulators that prevent solar battery overcharging. They also display the flow of power and battery status. Charge controllers are only necessary when you want to install an off­-grid solar system from rooftop systems to smaller setups on RVs.


Types of Solar Charge Controller 

The two types of charge controller to use when you want to install an off-grid are:

·        Pulse Width Modulation (PWM)

·        Maximum Power Point Tracking (MPPT) controllers.


Pulse Width Modulation (PWM) Solar Charge Controller

     Power Width Modulation Controller constantly supplies a minute amount of power in order to keep the battery topped off when it is full. As the battery gradually approaches its full capacity, the controller slowly reduces the amount of power that goes into your battery. They are quite simple and less expensive compared to MPPT controllers.


Maximum Power Point Tracking (MPPT) controller

      Like the Power Width Modulation Controller, the Maximum Power Point Tracking (MPPT) controller reduces the flow of power that goes into your battery as it approaches capacity. MPPT controllers are more efficient than PMP controllers because they can pair matching voltages from panels and batteries. They utilize the full power of your solar panel to charge a home battery system effectively.


Advantages of a Charge Controller

It regulates the flow of energy coming from the solar panels to the battery.

It prevents overcharging by monitoring the battery bank 

It prevents overload which can result to fire hazard.



Disadvantages of a Charge Controller 

It can cause a fire hazard when there is an overheating.

An overcharge can damage your batteries.

Reverse current can lead to internal damage of circuit and power supplies



Overload is when the current flowing from a circuit is higher than it can safely handle. It is caused by a faulty wiring or excess load voltage. When there is an overload, it can cause overheating and even a fire hazard. 


Preventing Overcharge  

Unrestrained voltage can burden your load, and make your inverter shut off. Overcharge can be prevented by reducing the flow of energy to the battery when it reaches a specific voltage. 

Voltage regulating is the most imperative function of all charge controllers. The flow of energy is regulated by some controllers when the current is fully switched Off or On. This is referred to as "On/Off Control". Others gradually reduce the current, and it is called 'Pulse Width Modulation'. Signs of possible overcharge that can damage your batteries and show a problem with your controller are:


a. Voltage not reaching the appropriate set points in your battery.

b. Batteries bubbling severely.

c. A lot of moist accumulation on battery tops

d. Not getting the expected capacity from your battery bank. 


Display and Metering 

Displays on charge controllers range from a single red-light indicator to digital display of voltage and current. It helps to keep track of the energy available in your battery by indicating the system function and status.