Wire Gauge Required Question
For some reason I just can't understand the various wire gauge tables, and I have tried to, so I am hoping somebody will take pity and do all the work! :) One table that I can follow says that for...
Forum Discussion
tenbear wrote:BFL13 wrote:
Thanks. Ok for a "single set of conductors" what "distance" do I use? 60 ft round trip or 30 ft from controller to array?
My panel is Voc about 37v. Do I use that for the voltage or do I use "24v"
( I did say that I got confused using the usual tables for this whole thing)
And last but not least, what voltage drop is acceptable on the array side of the controller so I don't lose any amps at the battery where I have a "24v" 230w panel and an MPPT controller to a "12v' battery bank?
I THINK the calculator assumes the current travels there and back so you would use 30'. I'm not sure on this point.
A 230w panel would put out ~10A at 24v under ideal conditions, so I would use 10A, but 8A is probably a more real life number.
The voltage is only used to calculate percent, I think you are more interested in voltage drop. In any case the Voc is the open circuit voltage and it will be lower when pushing current through a load. I would use 24v.
As far as what is an acceptable drop, smaller is better. Its a trade off between voltage drop and cost.
I just went thru the calculation and the calculator uses double the entered length so use 30'.
