[Streetdoctor]

What are you guys using/doing to protect the solar cables on the roof?

Later this week I'm going to install 3 100W Renogy panels in parallel with these https://www.amazon.com/Signstek-Branch-Solar-Adaptor-Connector/dp/B00FWO6ARG

but I'm confused with how to secure the actual cable to the roof. The panels are most likely going to be mounted using aluminum "L" stock and a rhino rack roof rack.

I'm concerned mostly with UV protection and cable rattle. I'm mounting the panels in the center of the roof and planning on running the cables through the backup camera.

Are you guys using VHB tape directly on the wire? Wire inside PVC pipe with VHB tape? I don't want water to pool up around the cables either. I figure I can mount the 3 to 1's underneath the panels for sun protection but I'm uncertain on how most people are securing them. It seems this is a step while trivial, most people don't document in their builds. Can I gorilla tape the adapter cables to the back side of the panels? What about the rest of the exposed positive and negative cable on the roof (about 5' in my case).

 

[phil]

I'm going to use 1 layer of electrical tape on the wires, then mount the wires to mounting tabs Dicored to the roof or to the side of the panel.

https://www.menards.com/main/electrical/wiring-accessories/cable-ties/gardner-bender-reg-1-x-1-black-mounting-base-5-ct/p-1444430993158-c-6443.htm?tid=-6463073531449117930&ipos=58

 

[RDinNHandAZ]

Good advice Phil. I let mine lie on the roof and the noise of them slapping on the roof on bumpy roads is incredible. Now I have them in 1/2 “ pipe insulation now but they need the wire tie treatment with taped squares to the roof. Even under the panels they need attaching.

 

[Streetdoctor]

I'm going to use 1 layer of electrical tape on the wires, then mount the wires to mounting tabs Dicored to the roof or to the side of the panel.

https://www.menards.com/main/electrical/wiring-accessories/cable-ties/gardner-bender-reg-1-x-1-black-mounting-base-5-ct/p-1444430993158-c-6443.htm?tid=-6463073531449117930&ipos=58

perfect thanks!

 

[Josh Cissell]

If I remember correctly, I zip tied them then used gorilla tape to hold them to the roof. Can't say I've ever heard them moving around.

Sent from my SM-P900 using Tapatalk

 

[Streetdoctor]

I figured it was a non-issue. Thanks guys! I’m waiting on roof rack mounts and panels and I’ll hopefully have it mounted up by next weekend.

 

[Streetdoctor]

My panels are mounted on my roof rack about dead center in the roof. Initially I wanted to run the wires through the backup camera but that's going to end up being about 30' of cable total. I'm using 8AWG wire so it's probably fine but I also picked up one of these-

[ame]https://www.amazon.com/gp/product/B0111RNZDY/ref=od_aui_detailpages02?ie=UTF8&psc=1[/ame]

in case I wanted to drill the roof. This way the cable run would be about 12' total. The flanges on this thing are just narrow enough to rest on the top of a ridge in the promaster roof with quite a bit of overhang. I figure I can build up around it with VHB and use a lot of Dicor. My question is for those of you who have drilled the roof what are you using to protect the cables from the sharp edge? Also, is there any reason I can't drill into one of the channels that run across the roof for easy cable routing down a wall?

Thanks in advance.

 

[phil]

grommets
https://www.menards.com/main/search.html?search=rubber+grommet&ipp=36

You could use something like this or a plastic version,
https://www.homedepot.com/p/Halex-3-8-in-Non-Metallic-NM-Twin-Screw-Cable-Clamp-Connectors-5-Pack-20511/100133208

I don't see why you can't use the channel as a raceway as long as you don't plan on screwing into it.

 

[Streetdoctor]

Thanks!

I'm really considering wiring in series and just using the backup camera. I could get away with 14AWG wire (2% loss) inside some loom with a 10A inline fuse and a tiny hole. The solar is really just supplementing my B2B charger and I don't think shading will be an issue. If I had unsatisfactory results I could plug the hole in the backup camera and drill the roof for 8AWG.

Reading more about the MPPT I bought (Victron) it requires battery voltage + 5V to turn on and the Renogy Eclipse panels have an optimum voltage of 17.7. I think that leaves me no choice but to run in series or return these panels and get a single Renogy 280w mono.

Searching locally all over for any single panel in the 300W range has so far been unsuccessful.

 

[Winston]

Cut-Off those Connectors & that Extra Solar Panel Wire

We were surprised how awkward our solar panel wires (too long) and connectors (too large with no effective way of 'paralleling' three of them) were. Add to that the 'box' many use to combine their panels and route wiring to the interior.

We cut-off those connectors and trimmed the cables as appropriate. Our rear panel wiring comes forward on the roof to the middle panel where it 'intersects' the middle panel cable, in turn, the middle panel cable comes forward to intersect the forward panel. Only the front panel cable continues and enters the van roof through appropriate caulked grommets.

At each of those intersections we stripped a section of the 'target cable (i.e. where the rear cable intersected the middle panel and where the middle panel cable intersected the front panel), wrapped the 'joining' cable around the 'intersected' cable, soldered and electrically taped.

The advantages of this arrangement are the shortest cable runs, no excess cable to 'stow/affix' and no cumbersome connectors or junction boxes. And, pertinent to this thread, as all the wiring was at one end of the panels, it was easy to attach the cable to the roof as it 'passed' each of the panel mounting brackets.

In short, there's nothing magical about those connectors and, by dumping them, you have the flexibility of adjusting cable lengths to fit your panel layout.