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JimM68's avatar
JimM68
Explorer
Jul 10, 2015

My solar install!

I could swear I posted about this somewhere, but can't find it for the life of me...

I speent the last couple weeks filling the roof of my monaco with solar panels!

I started with 4, and liked it so much I added 2 more today to max the system out.
On a sunny day I am getting 50, that is FIFTY amps into the batteries.

Panels are Hightec Solar, 150 watts, 18 volts no load, they measure 27" by 60", and are american made in Michigan, $165 each ish, free shipping, ebay.

Charge controller is an Outback 60 amp MPPT, just under $600 on ebay.

I used 70 feet of 8 gauge wire, and 18 feet od 4 gauge. Wire is expensive.

I made my own brackets out of alluminum barstock and angle stock, and mounted the panels a couple inches off the roof to allow air cisrculation under them. The first 4 panels are tiltable in either direction.

I maade a combiner box out of stuff from home depot. The panels are wired in series pairs, and the 3 pairs are combined together on bus bars, with 4 gauge wire going down to the controller. I brought the wires down behind the baathroom closet, then back. The controller mounts behind the magnum inverter, 4 feet from the batteries. Pos goes right to the battery, neg to the "upstream side" of the shunt for the mangum bmk battery monitor.

I normally plug in in storage, I leave the fridge on, and the inverter, and other stuff. I haven't plugged in in a week, and the batteries are at 88%!

I'll get some pictures up, I'm on the wrong computer for that now.
  • JimM68 wrote:
    My thinking was, since just a partial shading on one panel can take out a series set, 3 series sets would help eliminate shading as a problem, while still providing the mppt controller with enough voltage to do it's thing.
    That depends. My 3 series panels with bypass diodes function better than parallel in partial shade. With 3 bypass diodes/panel I do better than parallel with 0.67 panel in the sun since parallel would have no output. Ditto 1.33, 1.67, 2.33, 2.67. 1.0, 2.0 and 3.0 panels in the sun is basically the same between parallel and series. This is all part of the "magic" of MPPT.

    If the series panels do not have bypass diodes then you are correct that parallel would be better in partial shade.
  • dtappy3353 wrote:
    This may be a stupid question however, is there a way to unlock and tilt a panel from the ground without climbing up on the roof? :o
    Perhaps but I've never seen one. I've seen a few motorized tracking systems but nothing that was practical for a RV roof.
  • This may be a stupid question however, is there a way to unlock and tilt a panel from the ground without climbing up on the roof? :o
  • 2oldman wrote:
    JimM68 wrote:
    . The panels are wired in series pairs, and the 3 pairs are combined together on bus bars, with 4 gauge wire going down to the controller.
    Good idea... you're running 24v then to the controller...? And a 12v battery bank?

    With that controller you could do all 6 in series ( which I do). Look forward to the pics.


    I'm reading 33 volts and change off each pair, loaded. So yes, I coulda parrelleled them all.

    My thinking was, since just a partial shading on one panel can take out a series set, 3 series sets would help eliminate shading as a problem, while still providing the mppt controller with enough voltage to do it's thing.
  • rjxj wrote:
    You're ruined. From now on it's nothing but boredom. Walk over and check the monitor, yep charging. Walk over and check, full. Check again, full......


    ROTFLMFAO!!!!
  • You're ruined. From now on it's nothing but boredom. Walk over and check the monitor, yep charging. Walk over and check, full. Check again, full......
  • JimM68 wrote:
    . The panels are wired in series pairs, and the 3 pairs are combined together on bus bars, with 4 gauge wire going down to the controller.
    Good idea... you're running 24v then to the controller...? And a 12v battery bank?

    With that controller you could do all 6 in series ( which I do). Look forward to the pics.