cable routing for solar - vent pipe or drill roof?

[urbanMark]

Hello Everyone,

First post here. I'm sure this has been asked before and I did search but came up empty.....

I'm installing solar on my 2011 Eclipse Milan 25RKS TT. I've already built a custom enclosure for my dual AGM batteries and wired up the MPPT controller, breakers, fuses, disconnects, etc (I'll add some photos if I can figure out how), but the one remaining task is to route the cables from the roof to the controller. My fridge is near the rear of the trailer, so that isn't an option, and unless I want to tack conduit to the outside of my trailer (yuck), I'm looking at one of the following:

1. Use the grey water vent pipe. This comes out under the bathroom sink and is conveniently next to where all the electrical comes up from under the trailer - so I wouldn't need to cut a new hole in the bottom of the trailer. It would also keep the wiring out of site and away from storage areas. My concern is fishing the wire out of the pipe and sealing the hole well enough to prevent a smelly trailer.

2. Drill the roof over the bedroom closet. Straight forward and shortest cable run, but the closet is over the main storage bay - so wires would run through the storage bay (to get under the trailer) and would be a snag point for loading/unloading the storage area. The closet is also quite narrow and I'm sure the wires would be visible no matter how well I tried to conceal them.

Anyone had experience with the vent pipe method? Other options I should consider? Ideas for dealing with the wires through the storage bay?

Thanks!
Mark

[Dave-Sparky]

Clay Smith wrote:
Mark,
Up on the roof, you remove the vent cap from the grey vent pipe and fish the wire down inside the wall beside the pipe without it ever entering the pipe. If the hole through the roof for the vent pipe isn't large enough for the wire to enter beside it, you may have to remove the entire vent cap form the roof to enlarge the hole. Then reinstall vent cap while sealing it down with some fresh Dicor sealant.

This is what I did for mine

[westend]

Combiner box made from a 2" LB, the solar panel wiring is lead through a weatherproof box entry fitting. The two buses are fastened into UHDP standoffs (fastened from below) and everything is epoxied in place:

(I have # 4 from the combiner box piped on the exterior of the trailer sidewall, to the controller location).





Bus box made from 4" weatherproof junction box. The drilled and threaded 3/16" x 3/4" copper bar is fastened as above:

[Almot]

If you use "proper" parts ;), Gorilla glue becomes optional.

My Big Baby breakers box has bosses on the bottom to attach it to the wall. Insulated mini-buses are screwed to the box from inside, and because of those "bosses" the screws on the buses don't protrude through the box too far. I still put Crazy Glue under the buses, but it would hold without the glue as well.

Big Baby Box - note the bosses with mounting holes. Holds 2 buses and 4 breakers. It's smaller than it looks, 8x5x3 inches.

Insulated mini-bus, red Pos and black Neg. With buses raised on the insulators, it is also easier to access them than if they were flat on the bottom.

With 2*250W panels I didn't need this box for solar cable, obviously. You don't need a J-box for 2 panels in series. The box is for wiring battery, loads and controller.

[Colo_Native]

allen8106 wrote:

Colo Native wrote:
I went down beside my vent and took the panel off in the bathroom to run down made J box like this

How did you attach the buss bars?

Gorilla glue

[urbanMark]

westend wrote:
Nice job on the box! I like what you did with the cover extending over the controller, good design!

Thanks!

austinjenna wrote:
Excellent job on making that box. I am not as crafty so mine would have been some old amazon box covered in duct tape. Yours is almost as good

Thanks! Making boxes is actually pretty easy if you have a table saw and a pocket hole jig. Weatherproofing wood isn't that hard either - epoxy topped with a good exterior paint does the trick. Duct tape over the old amazon box is a great idea except good duct tape an't cheap :S

Looks like I may have to wait a while to get the panels mounted - forecast says solid rain for at least the next week.

[allen8106]

Colo Native wrote:
I went down beside my vent and took the panel off in the bathroom to run down made J box like this

How did you attach the buss bars?

[12thgenusa]

I went down through the vent pipe. Here's how I did it. Link

[austinjenna]

Excellent job on making that box. I am not as crafty so mine would have been some old amazon box covered in duct tape. Yours is almost as good:)

[westend]

Nice job on the box! I like what you did with the cover extending over the controller, good design!

[jauguston]

I ran mine through the side of the refer vent then down through the floor of the refer access from outside then down through the floor and on to the battery area. I used #4 welding lead from the roof to the controller for 800w of panels (6 panels). I like welding lead due to its flexibility. I see as high as 43A at 12V at times.

Jim

[urbanMark]

Thanks everyone! I hadn't considered running beside the vent pipe - that's a great idea!

BTW - As I mentioned, I had to build a custom battery box since none of the commercially available boxes would fit. While a metal box was my first choice, I don't have a sheer or a brake large enough to work with material that size - and due to the tight fit I didn't want to pay a shop and then keep going back for mods when it didn't quite fit. So I made the box out of Baltic ply, saturated it with expoxy, covered it in fiberglass, and painted it with exterior paint. Should hold up fine.

Here is the box with the lid off -


And lid on -

[BarneyS]

SoundGuy wrote:

urbanMark wrote:
I'll add some photos if I can figure out how ...

Upload your pics here, copy the url, and paste it into your post. Use preview to ensure your pics aren't too large but if they are just size them accordingly by adding "width=450" or some similar number so the pic size is to your liking.

Soundguy,
If you use the photo posting app that you linked to, there is no need to preview or re-size your photo. The app does that automatically so the pictures will be the proper size for use on our forums. All you need do is copy/paste the URL as you said.
Barney

[rkentzel]

I used something similar to this went down thru the closet


https://www.amazon.com/dp/B00KV1PFS0?psc=1

[Colo_Native]

I went down beside my vent and took the panel off in the bathroom to run down made J box like this