Traditional Pulse Width Modulated (PWM) solar charge controllers force your solar panels to operate at the same voltage as your battery bank during charging. They tend to be less expensive than MPPT (Maximum Power Point Tracking) charge controllers, but they're also less efficient. See our video on the differences between PWM and MPPT charge controllers below.
Read more +altE carries a wide selection of leading solar brands, including an excellent variety of the best PWM solar charge controllers. Choose from trusted names such as Blue Sky Energy, MidNite Solar, Morningstar, and Xantrex, with value-based price points ranging from $50 to $300. Depending on your preferences, budget, and solar energy setup, you can select a PWM solar charge controller that flawlessly fits your specific needs.
Are you trying to weigh your options between PWM and MPPT charge controllers? Watch the following video to better understand the difference between PWM vs. MPPT charge controllers and what it means for your solar setup.
How does a PWM solar charge controller compare to MPPT?
Once you know what size of solar charge controller to look for, identify which type is right for your application: MPPT or PWM.
A PWM (Pulse Width Modulation) charge controller features a battery that is connected to the solar energy source via an electronic switch. When the battery reaches a full charge, the electrical current is gradually reduced until it arrives at a low-maintenance state (where it will then stay).
Generally, we only recommend PWM charge controllers for small-scale applications where the nominal voltage of the solar array matches the battery bank voltage. If you are planning a solar energy system to serve a larger property, then a PWM charge controller may not be the best-suited option.
Let’s say you are searching for the best charge controller for use with a solar setup at a small cabin you only use on some weekends and holidays. In this case, a PWM charge controller may be ideal. However, if you are setting up a full-time home with an off-grid system and want to maximize power transfer to your storage batteries, then an MPPT charge controller would be a better choice. And if the nominal voltage of your solar panel array is going to be different from your battery bank’s voltage, you’ll be required to use an MPPT controller instead of a PWM. This is always going to be the case with 48V battery banks.
No, PWM charge controllers are unable to communicate with each other. So it’s not possible to wire two in parallel.
PWM charge controllers are not designed with user-programmable settings for charging parameters, so it is not possible to make customized adjustments.
For optimal safety and performance, mount your charge controller in a well-ventilated area. Provide a minimum of 9 inches of clearance around the charge controller. Proper clearance is essential because the charge controller converts the excess voltage into heat (released into the surrounding air).
One of the most significant advantages of using a PWM charge controller is its cost-efficiency. It is, by far, the most cost-effective method for achieving consistent voltage battery charging. Also, this type of solar charge controller is engineered to maximize battery life, which can contribute to long-term savings.