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big_buford's avatar
big_buford
Explorer
Feb 02, 2013

Solar install

My day has finally come! I've been piecing together a system over the last 6 mos and am ready to begin the install.

I have 4 105ah agm wired in parallel, 2-210w Evergreen 12v panels
and 2-145w DM solar panels 12v for 710 watts.

Controller is a Xantrex 60-150 MPPT.

I've been reading solar threads for quite some time and it seems when you think you have the best route planned out, another post makes you re-think things.

The plan, as it stands now, is series both sets of like panels for a 24v input to the controller. The trailer (40'toybox) is pre wired with 8 ga wire. Isc on the 210w panels is 12.11a, Isc on the 145w panels is 8.37a so 20.48a @ 24v.

I will continue the 10ga wire from both sets to a combiner box and use the pre wired 8ga to the controller approx 15-18 feet. Then 6ga from controller to batts. 60 amp Bussmann hi-amp fuse/circuit breaker before controller and 70 amp of same from controller to batt. They make 60-70-80 amp. Manual said 75 amp at batt's.

I am close to max on the 8ga from combiner to controller but there is still a little wiggle room according to wire chart in manual.

It states, 20 amps of 8ga @ 12v is good for 11.1 feet. For 24v DC system multiply distance by 2.

No plan to upgrade, only wanted to cry once :B

What say ye ! Thanks

26 Replies

  • Is the Vmp close on the different panels?

    Otherwise good to go. Post some pics and you should easily make renoman69's solar hall of fame.
  • tanman32225 wrote:
    I would love to see how you made it and affixed it to the camper. Also what is your estimate in dollars constructing it. solar power is something I have been thinking about for some time. Any pictures would be nice.


    Going to do a nice write up with pics, my first crack at this so thought it better to ask some of the more experienced here if this is the best way to wire things up. Could also do 48 volt system but didn't think that would be the best way to go with different size panels?
  • BFL13 wrote:
    I am confused about your amps. 710w would be approx 45amps Isc with a 12v system.


    With 20 something amps with 24v system, the MPPT should make up amps from voltage to add to that 20a and get at least 45amps total.

    Or that could be all wrong.


    You are correct, should have approx 18 amps before controller and a bunch more after controller.
  • Wow!!!. Thats a lot of solar (close to 50 amps at full charge capacity) for 420AH of batteries. Except for running Air Cond you should never need a generator

    Nice System :)
  • I am confused about your amps. 710w would be approx 45amps Isc with a 12v system.


    With 20 something amps with 24v system, the MPPT should make up amps from voltage to add to that 20a and get at least 45amps total.

    Or that could be all wrong.
  • I would love to see how you made it and affixed it to the camper. Also what is your estimate in dollars constructing it. solar power is something I have been thinking about for some time. Any pictures would be nice.

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