Any way to combine these panels?
I was asked to check on a neighbor's batteries while he was away for the summer. Battery voltage was 24.0, so I knew something was wrong. Turned out that the Trace C40 controller had died. OK, easy enough. But while inspecting the system I found that he had installed two 120W panels (Vmp 17.6V) in series and two 208W panels (Vmp 28.71) in parallel, with the two pairs paralleled into the controller. Obviously he assumed that the 208W panels were "24 volt" panels and would work. I don't see how he can use all of the present panels together. Ideas?