I am trying to match a controller to panels. I thought I understood this solar stuff, but one thing has me a bit confused. First, here are the links to what I am looking at.
Grape Solar 250-Watt Monocrystalline Solar Panel-GS-S-250-Fab5 at The Home Depot
direct link to controller spec pdf
Notice on the spec sheet it has a maximum of a 270W panel for 60 cell panel which the one linked above is.
Let's start with the math (lets forget any losses or efficiency for the moment)
I * E = P So, for the panel 8.15A * 30.7V = 250.205W This makes sense.
Now with the MPPT controller and it's specs (max 270W panel and 20A output)
I assume it's going to convert the 30.7 Voc to a usable voltage for charging a 12V system (~14v)
Math again. So, the controller is dealing with 250W. And trying to maintain ~14v. 250W/~14v = ~17.85A This makes sense, sorta fits the specs and is what an MPPT controller is supposed to do.
Now after all this, The question is this...
Can I connect only ONE of those panels to that controller?
Mathematically, that is what I am seeing, but that doesn't click in my head. When I see the panel putting out 8A and the controller being 25A I figure I could connect 3 panels.
An additional question that I just want to confirm my thinking.
I have to watch that the Voc of the panel does not exceed the Voc rating of the controller.
And finally, any recommendations for a controller that can handle 4 of those panels (1000w)?
Grape Solar 250-Watt Monocrystalline Solar Panel-GS-S-250-Fab5 at The Home Depot
direct link to controller spec pdf
Notice on the spec sheet it has a maximum of a 270W panel for 60 cell panel which the one linked above is.
Let's start with the math (lets forget any losses or efficiency for the moment)
I * E = P So, for the panel 8.15A * 30.7V = 250.205W This makes sense.
Now with the MPPT controller and it's specs (max 270W panel and 20A output)
I assume it's going to convert the 30.7 Voc to a usable voltage for charging a 12V system (~14v)
Math again. So, the controller is dealing with 250W. And trying to maintain ~14v. 250W/~14v = ~17.85A This makes sense, sorta fits the specs and is what an MPPT controller is supposed to do.
Now after all this, The question is this...
Can I connect only ONE of those panels to that controller?
Mathematically, that is what I am seeing, but that doesn't click in my head. When I see the panel putting out 8A and the controller being 25A I figure I could connect 3 panels.
An additional question that I just want to confirm my thinking.
I have to watch that the Voc of the panel does not exceed the Voc rating of the controller.
And finally, any recommendations for a controller that can handle 4 of those panels (1000w)?