Published by sass at October 10, 2005 If you as a consumer are being offered a non-PWM controller, stop and think about how much the salesperson really knows about solar. Mass merchants may drive volume, but eventually you need help to understand such complicated systems. And if their salespeople have not been trained properly, then more often than not, you will get wrong advise. To buy a non-PWM controller for up to 5Amps is perhaps OK (your total loss would be $50). But lose $300 on a $3000 solar panel system because you chose the wrong controller, what a shame that would be. Read more to learn about what you need to know about charge controllers...