Talking Solar (405W) from old MH and putting in 07 Bounder. My question is I have to go 25 feet with #2 cable from combinder box to Controller (TriStar 45). Will #2 Cable be OK or do I need larger Cable? I have read so many pages on Solar installation and still lost. Thanks
RET ARMY 1980,DW Donna,"Tiny" (furkid)">. Class A, 2007 Bounder 35E, Ford V10"> w/Steer Safe,"> 4SAMS 6V, 525W Solar ">, TriStar 45 Controller,Tri-Metric 2020,Yamaha 2400, TOW: Honda CRV. Ready Brake. "Living Our Dream". NASCAR #11,14,18,20 LOVE CO,NM,AZ
With the 2ga you will have less than 1% voltage drop... You could use 6ga wire and still only have lose 2.5%.
If you haven't purchased the wire yet, you can save yourself a few bucks by using 6ga (which by the way has an ampacity rating of 102A).
You're fine and can use smaller wire as posted above. But 2 suggestions:
1. Post # panels, panel info, wire length of each panel to the combiner box, plus the 25', and the length to the batteries. You'll get more information.
2. Consider if you might instead use a MPPT controller or upgrade in the future. In that case the wiring considerations are different and you may want to use those considerations even with a PWM contoller.
2009 Holiday Rambler 42 Scepter with ISL 400 Cummins
750 Watts Solar MPPT 60 Controller
2004 Honda CR-V