Panel to Solar Controller Wire Size
As some of you already know, I'm piecing together a solar system. Controller is a Morningstar 45A PWM. Panels will be two 12V 150W wired in parallel. I'm going to be using a combiner box on the roof, ...
Forum Discussion
450/130 x8.2= 28a but less when flat.
15 ft pos and neg, #8 about 1/2 a volt drop
http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=2.061&voltage=12&phase=dc&noofconductor=1&distance=15&distanceunit=feet&eres=28&x=74&y=6
With 12v PWM the voltage drop panel to controller is less critical than from controller to battery. My old ASC manual says 1/2 volt array to controller is ok and 1/4 volt for controller to battery.
IMO #8 is the right amount. In your over-all set-up you have already decided not to try to squeeze the last amp out of it, just be reasonable and leave it at that. So it would be strange to worry about a milli amp or two by using fatter wire than # 8 for this part of the set-up. I would agree with fat wire from controller to battery, epcecially if you can share with the inverter's wires for part of that path for instance.
15 ft pos and neg, #8 about 1/2 a volt drop
http://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=2.061&voltage=12&phase=dc&noofconductor=1&distance=15&distanceunit=feet&eres=28&x=74&y=6
With 12v PWM the voltage drop panel to controller is less critical than from controller to battery. My old ASC manual says 1/2 volt array to controller is ok and 1/4 volt for controller to battery.
IMO #8 is the right amount. In your over-all set-up you have already decided not to try to squeeze the last amp out of it, just be reasonable and leave it at that. So it would be strange to worry about a milli amp or two by using fatter wire than # 8 for this part of the set-up. I would agree with fat wire from controller to battery, epcecially if you can share with the inverter's wires for part of that path for instance.
