MrWizard wrote:
what part about PRE EXISTING did you not see
All of it :)... Because brain wired to my eyes can't process this.
See for yourself: "I plan on buying a more modern controler at some point, but was hoping to get it working first with the existing parts, but now I'm uncertain".
More modern controller is not necessary, strictly speaking, if old PWM works. Though it won't work with 5 and more panels, because 5*6.1>30.
Now, existing panels - if they want to keep those - it's better/easier to use MPPT controller with those, than PWM. There isn't much sense in using existing panels though. It is better/easier to install 2*250W than existing 90W modules.
Now, about "getting it working". Panels - usually - work. They are aging, surface gets milky and scratched, output drops, but they "work". I would not use old panels for a new install unless in dire financial straits, but a purchase of several pieces of road construction equipment somehow doesn't fit in this picture. Existing panels as a temporary setup needed to get some energy right now, leaned against my shack, without mounting them - yes, maybe. Buying a new controller specifically for for old panels - not sure.
Thick wire in the picture is on the "battery" terminal, i.e. was used for a short run from controller to battery. #4 wire from 450W/12V panels wired in parallel is a different thing, this they will have to buy and install IF they want to keep the existing panels. Depending on the length, #4 might not be even thick enough for 450W.
But - yeah, sure, they can keep existing panels and get a new controller.
Sorry Mr Wiz.
