My question is in reference to the wire run from an rv-roof-mounted panel combiner box to an MPPT controller located inside the cabin.
GT panels are arranged in a 2x3 array (3 parallel strings of 2 series-wired panels each). Each panel 300W @ 32V. Panels and combiner box on top of an RV roof in AZ desert (hot, hot, and then hotter still).
My math gives me 14 combined amps (@63V) from the array. 10 awg 90-degree copper de-rated by .41 for high temps (159 - 176... the highest temp de-rating value in the table I'm referencing) gives me 16.4 amps.
My run will be ~ 20 feet max, and the only portion of the wire that will be actually be exposed to the extreme temps I expect will be at or near the combiner box itself.
So I'm thinking 10 AWG should be a good choice. Would you agree? Or should I go bigger still? For some reason it just seems small. Is my math screwy?
Also, what specific wire type/brand would you choose for this run and/or anything between the panels and the combiner box? The higher heat-rating the better, I'd think, but I don't really know what there is to choose from over 90.
GT panels are arranged in a 2x3 array (3 parallel strings of 2 series-wired panels each). Each panel 300W @ 32V. Panels and combiner box on top of an RV roof in AZ desert (hot, hot, and then hotter still).
My math gives me 14 combined amps (@63V) from the array. 10 awg 90-degree copper de-rated by .41 for high temps (159 - 176... the highest temp de-rating value in the table I'm referencing) gives me 16.4 amps.
My run will be ~ 20 feet max, and the only portion of the wire that will be actually be exposed to the extreme temps I expect will be at or near the combiner box itself.
So I'm thinking 10 AWG should be a good choice. Would you agree? Or should I go bigger still? For some reason it just seems small. Is my math screwy?
Also, what specific wire type/brand would you choose for this run and/or anything between the panels and the combiner box? The higher heat-rating the better, I'd think, but I don't really know what there is to choose from over 90.
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