Wire through roof for solar - leakproof

[absolutsnwbrdr]

PV junction boxes. Commonly found on the backs of solar panels, but you can buy them separately. I used one on my roof, and one on my rear hatch.

Drill a hole in your roof/hatch just large enough for your wires, but small enough to be covered by the junction box. Use a sealant on the the base of the junction box, and I added a couple screws to help hold the boxes in place, just for good measure. Remove the diode and metal tabs that come inside the box, and just make your wire connection in there. The lids have little silicon gaskets to keep water out, and o-rings to seal around your wires that exit the box and go to the solar panel.



I was looking for a picture of my installation, but the boxes are hidden under the solar panels. I believe these are the ones that I used: http://www.ebay.com/itm/PV-SOLAR-PANEL- ... 2570f0132d

[bc toys]

I like that box ideal and I have a question I have 1 battery and might add 1 more at best what size panel would I need I was thinking a 100 watt would be good with auto shut off so not to over charge it Need some advice on this one

[jss06]

Panel size depends on your power draw, If you draw 70AH during the night you need a panel that is large enough to carry the loads during the day and also replace the charge you used at night. The type of charge controller you use also has an impact on the efficiency of the panel. If you use a "normal" controller and a 12v panel, you will not get as much usable energy as if you used a mppt controller and a higher voltage panel of the same wattage.

When in Yellowstone, I used about 40Ah at night because I had my 12v fridge plugged in. After I fixed a loose wire, I was only able to recover 21ah with my high voltage panel and the mppt charge controller. (where I was parked was pretty much the worst case scenario for solar charging and it was overcast after I fixed the issue). I had to plug my car in and run it for about 20 minutes or so to adequately charge the battery.

I run a 190 watt 36V panel into a BlueSky 3000 MPPT charge controller. If the wire had not been loose, I would have recovered all of the power I used plus had some extra.

[Dave Nathanson]

Some great leakproof ideas here. Thanks for sharing.

[twinight]

I ran mine through the fantastic fan housing. I drilled a hole in the back of the housing to run the wires down inside the shell. The hole is 1/2" above the edge of the vent cover in the closed position. When the vent is closed, the hole is still covered by the edge of the vent cover to keep the water out.

[bc toys]

thanks John I will only be running a dvd player 12volts and a 12v fan and light

[Dave Nathanson]

My first thought was to run the solar wires through the edge of the roof vent's metal flange. That is how the old solar panel was hooked up. But those were much smaller wires, for a 5 watt panel. And that little panel was mounted flat to the roof. The new panel is 100 watts and mounted to a rack something like 4 inches above the roof. The new wires are 10 gauge and 1/4 inch diameter each, not because of high current, but to avoid voltage drop. But since that WAS my plan (for awhile) I figured this is the best time to replace the old rusty vent with the broken fan with a FanTastic vent. But these new wires are pretty stiff. If I ran them through the edge of the vent, they would need to U-Turn real quick like through the fan trim. Which seems like more trouble than it is worth. (On the other hand, I often overpay for trouble, so no big deal).

Instead, I'm just going to pop a hole in the roof, line the hole with some vinyl tubing to prevent chafing and cover with a 1-5/8" Stainless Steel ClamShell Vent $3. (West Marine model # 180349) And of course goop it up with silicone sealer. Since i can, I'm going to use enough clear vinyl tubing to cover those wires until they are safely up & under the solar panel. No rain will get in the end of that tubing if it was way up there under the solar panel.

Ah progress!
(he says after spending all afternoon getting that little $3 vent cover & some bolts.)

[Esteban]

Instapark aerodynamic glue-on (not screw-on) solar panel mounts can be ordered with a Surface-mountable Dual Cable Feed-thru Gland with Adjustable Grommet & Blanking Plug (you may need to click on IN-D to see one) to rout the wire(s) through the roof to the solar panel.