Solar Installation (Photovoltaic)
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Materials List
2 Uni-Solar 64W modules in parallel
7.7A operating current (full sun), 16.5V operating voltage, 23.8V open circuit voltage, 29" x 53.8" (each panel), Anodized aluminum frame is 1.25" thick
3/16"x2"x2" aluminum angle stock
1/4" stainless steel bolts, lock washers and self-locking nuts
Rubber mat material
Self-leveling RV caulk
Butyl rubber caulk
1.25"x1/4 lag screws
Weather proof electrical box
10 ga hook-up wire
6 ga cable
Connectors, silicon dielectric grease, fuses & fuse holders
Mornigstar 15A charge regulator.

NOTE: All electrical connections are steel wooled then greased with silicone dielectric grease prior to assembly. This procedure absolutely prevents corrosion.  It is well worth the extra cost and effort.  I assembled the PV charging system on my 5th wheel (7 panels, 4 golf cart batteries) in 1999 and have not found a bit of corrosion in 10 years.

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Of course, if you're not very daring, it's best to read the instructions.  I chose to use 10 ga. stranded cable with a UV rated coating to connect the panels in parallel and to the roof pass-through junction box and charge controller.  From the charge controller to the battery I used 6 ga stranded to minimize the voltage drop.
(Click on any image to see a larger version.)
Since PV cells are less efficient when they get hot, I made stand-offs from 3/16"x2"x2" aluminum angle stock and bolted them to the module frames with 1/4" stainless steel bolts, lock washers and self-locking nuts.  I later modified that construction with nut inserts that attach to the frame like Pop-Rivets.  This allows me to tilt the panels up when the sun isn't directly overhead or even remove the panels and set them on the ground.  In one of the figures below you can see the connections for the dismounted mode sticking out in front of the battery.  The extension cable is too long to fit in the battery box.
The last picture in this group shows me filing the sharp edges left by the cut-off saw so there would be no chance of them cutting into the roofing material.
(Click on any image to see a larger version.)
I made three "pigtails" (2 for connecting the panels in parallel and one to connect to the camper circuit) of 10 ga stranded cable and 2-terminal polarized DC connectors which I then connected to the terminals in the junction boxes on the under side of the panels.  When all connections were made, I attached the lid and sealed all joints & holes with caulk.  The last picture in the group shows a 2"x2"x 48" aluminum angle support rib hot glued and caulked to the back side of the panel.  We get a pretty heavy snow load in Michigan and I wanted to remove some of the stress by supporting the middle of the panel.
(Click on any image to see a larger version.)
Roof installation started with pieces of rubber truck bed mat to make up the gap between the support rib and the roof and to prevent wear on the roof.  I set the panels in place, drew extended lines around the stand-offs and drilled pilot holes in the roof through the pre-drilled stand-off holes.   I had to take a chance on drilling/screwing through an electrical cable because Lance wouldn't answer my request for diagrams.  I deposited a big gob of Dicor Self-Leveling Lap Sealant each stand-off location then set the panels back in place.  Being extra cautious to avoid stripping the wood by over tightening, I used 1.25"x1/4 lag screws to fasten the standoffs to the roof.  A little experimenting with a light duty torque wrench and a piece of 3/8" plywood gave me a pretty good idea of how much torque could be applied before the wood stripped out.  As you can see by the last picture in the group, there isn't much room left at the front of the camper roof.
(Click on any image to see a larger version.)
In the first picture in this group you can see the plug/socket/fuse connection that connects the panels in parallel.  The cables are taped to the roof with white duct tape to keep the wind from whipping the cables around.  As I do when I want to protect my ham radio antenna connections, I taped the connectors with electrical tape and then coated the tape with caulk provide a better moisture seal and to keep the tape from deteriorating.  The middle picture shows the weather proof electrical box which I glued to the roof with caulk then securely screwed to the roof through screw holes in the bottom of the box.  I then drilled a half-inch hole through the roof and into the end of an overhead cupboard where Lance designers located a "wiring closet".  Of course, before I drilled, I did a bit of investigation and measuring to make sure the hole would end up where I wanted it.  The last picture in the group above shows the charge regulator installed on the outside of the "wiring closet".
(Click on any image to see a larger version.)
On the left in the group above is a close up of the Morningstar 15 amp controller.  I have the 25 amp version in our 5th wheel because the seven panels provide  more than 25 amps under clear skies at high noon.  When we were hosting a campground in NE Yellowstone National Park I had to wire one panel direct to one of the battery banks to keep from blowing fuses . The last three pictures show the battery compartment "snakes nest" in our 915.

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