Are Cheap PWM Solar Controllers Really That Bad?
🎁 Free Diagrams: https://cleversolarpower.com
📖 My Best-Selling book on Amazon: https://cleversolarpower.com/off-grid...
Cheap PWM: https://amzn.to/3F38vbg
Are PWM charge controllers really as inefficient as people say? In this video, I put that claim to the test using a hands-on demonstration. I connect a 100-watt solar panel to a PWM charge controller and measure exactly how much power goes into the controller and how much actually reaches the battery.
But that’s just the start. I take things a step further by adding a second panel and wiring them both in series, then in parallel, to show you the real-world impact on power output and system efficiency. You’ll see firsthand why wiring panels in parallel is usually the better choice when using a PWM controller—and why series wiring with PWM leads to major losses. I also explain when it actually makes more sense to upgrade to an MPPT controller, especially once you factor in wiring costs and system size.
In this video, I also touch on how to set up a PWM controller for lithium iron phosphate (LiFePO4) batteries. This particular controller has a lithium profile, but if yours doesn’t, I show you how to set the correct charging voltage.
Finally, I break down when a PWM is still worth it. While MPPT controllers are more efficient, especially in mobile and larger setups, a PWM controller can still be a smart, budget-friendly option for small projects like powering lights or charging backup batteries.