Back of solar controller very hot!

[Warby12]

Yeah I think you're right about the small panels sailorchic. I just went to disconnect them and their open circuit voltage was 12 volts and they look very old to me.

Good point on the heat too, we were last out in winter (your summer) and now it's summer and maybe that's why the performance has dropped plus... Maybe the old controller is dying hence the high temp. Maybe one of the doohickeys inside has died and the other doohickeys are overworked.

Getting a new controller in a week so fingers crossed. We only run a fridge and led lights so I am under the impression these panels should be enough. Of course wiring needs replacing but if the controller is getting so hot, it must be getting a fair bit of input.

[hamburking]

Originally Posted by noelex 77

So watts = area of solar panels (in meters squared) x 1000 x 0.14

OR

watts = area of solar panels (in metres squared) x 140.

[noelex 77]

Originally Posted by hamburking

OR

watts = area of solar panels (in metres squared) x 140.

Indeed

I was trying to show where the figures came from. The 1000 comes from 1000w/sqm which is part of the STC definition and of course 0.14 comes from 14%.

If you want to calculate the number of watts for the NOCT requirement for example, you would substitute the 1000 with 800 for 800w/sqm. For a modern high performance solar panel you might substitute 0.21 for a 21% effecient panel.

[Ding Duck]

The small top LHS Panel looks as though it may have seen better days.
I would avoid using a MPPT Regulator on this set up as different panels and different Max Power's. Could cause the Regulator a lot of grief trying to find the best MPP.
If you Clamp Meter fir DC, suggest you measure each panels out put current. You may find you have voltage generated by the panel, but not delivering any real current.
Good Luck with it