[mrshowtime3]

Ok the easy answer here is probably to just get a negative ground controller but....

I was looking at this Grape Solar controllar
[ame]https://www.amazon.com/Grape-Solar-GS-PWM-40BT-Controller-Monitoring/dp/B01FFNNUSK[/ame]

I see in the manual that it is a positive ground. Would this matter if not using the load connections and simply putting all the load from the controller to the batteries? This is what Renogy has to say about a very similar controller they sell....

" You can still use a positive ground controller in a negative ground system as long as you do not use the load terminals on that controller. All your loads will need to be connected to your battery bank."

 

[RDinNHandAZ]

I don’t know the answer but Renogy and many others just as good as Grape make 12 volt negative ground controllers. Tracer is the manufacturer that for years supplied many companies. Why fool around? Do you just want to experiment? Go ahead and let us know how it works out.

 

[Winston]

I see in the manual that it is a positive ground.

Remembering that everything else in the van, including the battery, is negative ground, this will work only if you 'float' the solar panels and solar controller - - that meaning, nothing (electrical) on the panels nor controller can 'touch' ground.

We tend to agree with RD, why bother to take the risk . . . find a good negative ground controller and move on to other matters.