Wiring charge controller for solar q’s

[fred1diver]

hello everyone, ready to wire my charge controller to the batteries, looking in the manual but I can’t find the proper wire size needed, one is about 2 feet away and the other about 7, I was thinking about either 8 or 10 guage, what do you all recommend?
I will buy an ACR to add to my system to combine both batteries

 

[fred1diver]

Just re read the manual and the max size is 8ga.

 

[Davidasailor26]

What’s the amperage output of the controller? Depending on that you may want to consider a terminal block to a larger gauge, though it doesn’t sound like your runs are too long.

 

[High Current]

There’s a great chart here that will make you ABYC compliant:

http://assets.bluesea.com/files/resources/newsletter/images/DC_wire_selection_chartlg.jpg

You can estimate the amperage by dividing your panels’ total power rating by 12V (e.g. 300W/12V = 25A). It will likely be lower on the panel side but I’d need more details (nominal panel voltage, number of panels, series/parallel configuration).

 

[fred1diver]

I have 2, 100w panels that will be hooked up to a 40 amp controller

 

[High Current]

Your controller has plenty of margin so it will run cool and be easy to add more panels in the future. If it were me, I would just wire it with 8AWG as recommended by their directions and the chart I linked so that it can never be under-sized, no matter what anyone puts on the input or if the output somehow gets short-circuited.