MPPT Charge Controllers

MPPT Charge Controllers

The MPPT charge controller is the most efficient type of charge controllers on the market. Adding it to your solar panel system helps you to keep your battery safe and maximizes the efficiency of its charging process.

What does a charge controller do?

A charge controller is a crucial part of every solar panel system with a battery. Both a PWM (pulse width modulation) or MPPT (maximum power point tracking) controllers:

• protect the battery from high voltage of solar panels — PWM and MPPT controllers do it in different ways.
• block the usage of a deeply discharged battery
• don’t allow the battery to be overcharged
• prevent reverse current: at night electricity can flow from an energy storage back to panels, which can potentially be dangerous.

What is special about MPPT controllers?

Unlike a PWM controller, an MPPT charge controller doesn't simply limit the voltage of panels for a battery, but rather converts it into current at high frequency. This speeds up the charging process and allows you to use your solar array at its full power. Basically, the solar charge controller MPPT technology allows to find and maintain the “sweet spot” where voltage and current are set to maximize the energy production of panels. As a result this controller makes use of 90-95% of energy coming from solar panels. 

The higher the voltage, the better it is with an MPPT charge controller. In winter when it’s cold and sunny solar panels tend to reach their peak voltage. This is why this type of regulators becomes especially good during cold months — it’s 40% more efficient, compared to a PWM regulator. 

MPPT controllers are more internally complex than PWM controllers which results in slightly shorter lifespan — from 10 to 15 years on average. The downside of a MPPT controller is its cost — 5-10 times higher than of a PWM regulator.

How to choose a charge controller for a solar panel system?

An MPPT solar charge controller fits almost any solar panel system, whereas a PWM controller is more likely to be used only in situations where the voltage of panels is slightly higher than the one of a battery. But even in solar systems where both PWM and MPPT controllers can be used, an MPPT solar charger is 20% more efficient.

Look for two main characteristics in an MPPT charge controller: maximum amps size and maximum voltage. 

• Figuring out minimum amps size can be done like this: take the combined power of your solar array and divide it by the voltage of your battery. For example, if the power of your array is 900 watts and you are using a 24 volt battery, then the charge controller should be bigger than 900 W / 24 V = 37.5 A. 
• To determine the voltage of your array, sum the VOCs (open circuit voltage) of every panel in the array. During cold and sunny days panels can reach their peak voltage (Vpp). To make sure that it won’t hurt the controller, add 5V to the VOC of every panel. For example, if you have two 400W solar panels in an array, the VOC of each panel is 48.1V. The maximum voltage of a controller here must be bigger than (48.1V 5V) * 2 = 106.2V

To adjust the voltage and amperage of your solar panel system, you can play around with the connection of panels. Remember, that wiring panels in series gives you combined voltage and allows you to keep the current low. Connecting panels in parallel gives you combined currents, but voltage stays the same. Combination of two types of connection allows to adjust the system to the parameters of a charge controller.

Why buy from us

• Our distribution centers are located on both east and west coasts of the USA: California, Washington, Colorado, Texas, Florida, New Jersey, and Missouri.
• We guarantee the authenticity of all the products we sell.
• We process all orders within 24 hours and ship them within 48 hours.
• Delivery normally takes between 4-7 business days.
• All of our suppliers are trusted, top solar panel manufacturers.

We have a wide selection of solar charge controllers in stock. Call us, and our A1 SolarStore experts will answer all of your inquiries, help you choose the right product, and complete your order.