Solar Wire Management

[allen8106]

For those of you who have installed solar on your RV I would be interested in hearing what you have done with the rooftop wire management issue.

I'll have four panels with two #10 wires each needing to run between 10-14 feet to the combiner box so a total of eight #10 wires to manage. Outside of the obvious "conduit" answer what have you done to manage these wires? I'm planning on a tilt option so any wire management scheme needs to consider this issue.

Thanks in advance for your inputs.

[Homeless_by_Cho]

I just Dicor-ed the wires to my roof without drilling any holes. I don't want any unnecessary holes in my roof. I have driven over 30,000 miles without any failure of any type. I have a fiberglass roof. If you have a rubber roof, the rubber membrane MUST be tight to the underlayment or your rubber roof might start to lift.

LeRoy

[allen8106]

Hey gang, Here's an update on the eternabond tape on my solar panel wires. We made a 2400 mile round trip to western Arizona in January and back home and the tape didn't stay down in all places so I'm going to have rework the wire management plan.

Thinking about just screwing plastic wire clamps to the roof and covering them with Dicor.

[CA_Traveler]

I used a dab of Dicor to hold the wires and they haven't moved in 3 years. Small strips of tape held the wires in place for a few days until the Dicor set.

[allen8106]

MrWizard wrote:
Panels are usually lined up side by side
I left the wire loose under the panels used eternabond where they came out from under the panels and went to the fridge vent

I used a strip of eterabond tape every 2 feet but I'm not happy with the outcome!

Also due to space constraints mine are not lined up side by side.

[Almot]

If you think 130W panel is heavy to tilt, try 250W :)... It's really a 2-man job, very inconvenient to work on one corner at a time.


Without combiner box, when you only have #10 MC4 wire, adding a few feet of MC4 extension (for tilting) is very easy. TS MPPT 45 would still let you connect MC4 in series without combiner box, but TS 45 wouldn't. Better to scrape the tilt idea altogether. Flat 260W is very little, don't know about KS but for "mostly solar" living I would go for at least 100W more.

Mex - in "dry" Mexico UV is is a byatch. Worse than humidity. Will take thin piece of coated wire (like those they use on coiled cable with new microwave etc) over Polyethylene cable wraps any time. Still, better to hide any ties under the panel.

[MEXICOWANDERER]

Zip ties? Mex, - not where you are, for sure. At these latitudes sun really does a number on polyethylene.

Black ties will outlast natural white ties something like a thousand to one when exposed to UV. If you're worried massage a layer of silicone grease onto the tie before assembly.

Much more important is the insulation on the wire itself. EDPM* or Teflon makes the best UV proof insulation material. Next would be cross-link polyethylene.

*DLO Diesel Locomotive wire.

[MrWizard]

Panels are usually lined up side by side
I left the wire loose under the panels used eternabond where they came out from under the panels and went to the fridge vent

[allen8106]

Almot wrote:
Exactly - What panels and what controller :). Alright, let's assume - for the lack of response - that he had checked the specs and estimated max string voltage in his intended area of camping.

Zip ties? Mex, - not where you are, for sure. At these latitudes sun really does a number on polyethylene.

To the OP:
You are planning on tilted. Depending on where you are and who you are, it might be worth to reconsider the plan. I planned tilting too, can do it to either long side of trailer, but I don't do it. Don't enjoy it and, luckily, don't need it with my solar wattage and my energy needs. Get more wattage and forget the tilting, it's not fun, especially if you stay put less than a week.

Wire management on the roof does not need to consider tilting - not much. You run the cables to the pivoting point and clip the rest to the underside of the panel, together with the connector (to keep it away from sun and rain). If you have more than one possible pivoting side (tilting to 2 opposite sides), you run cable to some point on the panel that will most likely remain low during the tilting, and again clip the rest to the panel, with some slack to allow for tilt. You might end up with a length of coiled cable under the panel - especially with tilting, it complicates things.

Panels are Kyocera KC130TM, 21.9 VOC

Controller is Morningstar TS-45

My wires are now too short to run to the pivot point. Bad planning on my part but it it what it is now unless I want to re-run all the panel wiring. It's an excellent idea though.

I was planning to try an NOT to tilt unless I need to but want the option. I'm not a fan of climbing on the roof either. Plus the panel assembly is heavy to lift up and tilt.

[Almot]

CA Traveler wrote:
Somewhere I read that the average person tilts 7 times maximum. :@

In his lifetime, yes. Then he is fed up and stops doing it. I didn't even make it to 7.

[CA_Traveler]

Somewhere I read that the average person tilts 7 times maximum. :@ That's 14 trips up on the roof. 😞

[Almot]

Exactly - What panels and what controller :). Alright, let's assume - for the lack of response - that he had checked the specs and estimated max string voltage in his intended area of camping.

Zip ties? Mex, - not where you are, for sure. At these latitudes sun really does a number on polyethylene.

To the OP:
You are planning on tilted. Depending on where you are and who you are, it might be worth to reconsider the plan. I planned tilting too, can do it to either long side of trailer, but I don't do it. Don't enjoy it and, luckily, don't need it with my solar wattage and my energy needs. Get more wattage and forget the tilting, it's not fun, especially if you stay put less than a week.

Wire management on the roof does not need to consider tilting - not much. You run the cables to the pivoting point and clip the rest to the underside of the panel, together with the connector (to keep it away from sun and rain). If you have more than one possible pivoting side (tilting to 2 opposite sides), you run cable to some point on the panel that will most likely remain low during the tilting, and again clip the rest to the panel, with some slack to allow for tilt. You might end up with a length of coiled cable under the panel - especially with tilting, it complicates things.

[bighatnohorse]

CA Traveler wrote:
All you need is a dab of Dicor.

This works.

[CA_Traveler]

Mex My wires are secured after the pigtails and MC4 connectors.

[BFL13]

allen8106 wrote:
For those of you who have installed solar on your RV I would be interested in hearing what you have done with the rooftop wire management issue.

I'll have four panels with two #10 wires each needing to run between 10-14 feet to the combiner box so a total of eight #10 wires to manage. Outside of the obvious "conduit" answer what have you done to manage these wires? I'm planning on a tilt option so any wire management scheme needs to consider this issue.

Thanks in advance for your inputs.

What four panels and what controller??? Your first limit is the total Voc intake for the controller in its specs.

That says whether you can have your panels in series (added Voc) or not. You might have to go series-parallel to stay under the controller's Voc limit.

NOW you can plan your wiring layout. The Dicor every so often along the way to keep the wires from flapping in the wind while driving makes good sense to me. But Mex makes a good point about ever changing things afterwards during say, an upgrade or a failure of a component. ( I have no experience with that yet, but just got a Class C, so might be going the roof route--not sure yet)