panel wire AWG to controller
Ok so the ts-MPPT-60 is on its way, I put the card board cut outs on the roof just to make sure the panels fit as I thought and now on to more planning. I check a few voltage drop calculators for t...
Forum Discussion
The voltage on that path would be less than the Voc at the panel temperature, so your calculation should be for the approx Vmp.
Eg, my 230w panel rated at 37Voc is at 34Voc out in the sun, but the measured voltage between panel and controller on mine is more like 29.3v at the panel and 29v at the controller input terminals (1% drop) I believe the 29ish volts is what the controller chose for Vmp at the time I measured. (Rated panel Vmp is 30v)
IMO it is not worth fine tuning for AWG on that path, since your panels are flat and so already operating below optimum, which is why to have so many panels, so who cares about a little loss here and there elsewhere in the set-up?
I prefer this calculator tenbear posted since it makes it clear the distance is one way for a pair, so you don't have to wonder if you should double it or not like some of those other tables make you wonder.
http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=2.061&voltage=12&phase=dc&noofconductor=1&distance=60&distanceunit=feet&eres=8&x=42&y=5
Eg, my 230w panel rated at 37Voc is at 34Voc out in the sun, but the measured voltage between panel and controller on mine is more like 29.3v at the panel and 29v at the controller input terminals (1% drop) I believe the 29ish volts is what the controller chose for Vmp at the time I measured. (Rated panel Vmp is 30v)
IMO it is not worth fine tuning for AWG on that path, since your panels are flat and so already operating below optimum, which is why to have so many panels, so who cares about a little loss here and there elsewhere in the set-up?
I prefer this calculator tenbear posted since it makes it clear the distance is one way for a pair, so you don't have to wonder if you should double it or not like some of those other tables make you wonder.
http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=2.061&voltage=12&phase=dc&noofconductor=1&distance=60&distanceunit=feet&eres=8&x=42&y=5
