mppt vs pwm

BFL13 wrote:

jrnymn7 wrote:
O.K., thanks. I'll have to do some reading up on PWM controllers, to see if they're anything more than simply a high frequency "on/off" controller, with no way of adjusting for changes in panel voltage.

They don't do anything to panel voltage. There is no buck converter. Panel voltage is battery voltage plus a bit for line loss. What you want to study is your panel's IV curves. All the answers are right there! Go in at the Vbat you are at and that is your "expected amps" at STC. (Isc of the moment)

How do you know you are at STC? Simple. Disconnect panel and measure across its terminals with an ammeter. That is the Isc of the moment. Could be anything up to rated Isc or above.

On a sunny day with the sun high in summer, with the panel aimed at the sun, you should get at least rated Isc. Next check is what are the batteries getting? Re-connect and now you should see the same amps to the battery on your Trimetric or whatever.

You should be getting close to the Isc of the moment or else you have a wiring or connection problem somewhere.

12v PWM is way too easy! None of that anxiety-prone MPPT complicated stuff to worry about whether you are getting your money's worth of amps. :)

lol, I hear ya.

I did come across an article though, by morningstar, about their lastest and greatest new technology...

pwm!

I'll post it if anyone wants to read it.