Getting wire down from roof

RoadTurtle

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Mar 30, 2022
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I had a plan.... apparently not a good one :(

Original plan was to pull wires using the existing wire going to the roof gland and over the hole with a project box, used as a combiner. For once, wires are stabled or otherwise restrained.

There are two sewer pipes going up in the same cavity I wanted to use. What options do I have to attach to the roof to get 4 wires down through the roof?

Side note, the wires connected to the roof gland were so bad, one came apart in my hand, the other required a gentle tug to separate it.
 

12VoltInstalls

life passes by too quickly to not live in freedom
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I’d use a weather head on the side of the house if it were me.
That’s a good option; maybe better would be a plastic junction box with weathertight conduit fittings and pvc conduit down to an LB because the existing install…
the wires connected to the roof gland were so bad, one came apart in my hand, the other required a gentle tug to separate it.
…clearly left a lot to be desired.

You can use another weathertight box to receive weathertight “glands” for the solar cables.
 

RoadTurtle

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I brought my PV cables down through the refrigerator vent. That was the easiest way to go for me. If that hadn't worked, I would have installed a roof gland.

Instead of bringing four wires down, can you combine them together, so it's only two wires?
I decided to run two independent strings. If I had gone with one SCC, I could have used existing wires. BUT, it was the desire to keep pass and driv side strings independent. Right this second, I'm regretting that decision :)
 

HRTKD

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I decided to run two independent strings. If I had gone with one SCC, I could have used existing wires. BUT, it was the desire to keep pass and driv side strings independent. Right this second, I'm regretting that decision :)

My opinion on that is that the only time you'll regret using two solar charge controllers is when you have to bring the wires from the roof into the RV. I currently have four wires coming in through the refrigerator vent.

From a production standpoint, it's been my experience that if one set of roof mounted panels is in the shade, the other set is, or will be, in the shade also. To work around that problem, I have a pair of panels that I deploy on the ground where there isn't any shade.
 

RoadTurtle

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My opinion on that is that the only time you'll regret using two solar charge controllers is when you have to bring the wires from the roof into the RV. I currently have four wires coming in through the refrigerator vent.

From a production standpoint, it's been my experience that if one set of roof mounted panels is in the shade, the other set is, or will be, in the shade also. To work around that problem, I have a pair of panels that I deploy on the ground where there isn't any shade.
Too funny, I'm looking at the wires that were originally run fromthe roof. 10g to the factory SCC, and 6g to the battery. I could have easily used those wires and saved myself a lot of work. BUT, as you very well pointed out, the reason I went with 2, was actually due to shadow issues :) Original plan is still the correct plan. I can't put the hole where I want to, so my 3rd(?) choice is slightly offset from the bathroom fan instead of directly behind it. I do wonder why in the world front gray and black tanks have separate vents. To me it would have made more sense to combine them into one stack, but given some of the other not well thought out decisions in this trailer, why am I surprised?
 

Checkthisout

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Too funny, I'm looking at the wires that were originally run fromthe roof. 10g to the factory SCC, and 6g to the battery. I could have easily used those wires and saved myself a lot of work. BUT, as you very well pointed out, the reason I went with 2, was actually due to shadow issues :) Original plan is still the correct plan. I can't put the hole where I want to, so my 3rd(?) choice is slightly offset from the bathroom fan instead of directly behind it. I do wonder why in the world front gray and black tanks have separate vents. To me it would have made more sense to combine them into one stack, but given some of the other not well thought out decisions in this trailer, why am I surprised?

It can use a single vent at the roof but it has tie in above the toilet bowl line

In other words imagine you didn't empty the black tank and then filled the toilet up. It would then run over into the gray if not for this rule.

As long as the layout allows a lateral connection above that line, they can combine them but most rv's and trailers do not.
 

RoadTurtle

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Mar 30, 2022
Messages
159
Got the wires down today... it was a bit challenging. I wanted to use a cute aerodynamic gland housing, but just couldn't find one big enough for 4 8mm wires. So, my project box combiner is partially in the slip stream, with wires to SCC coming up through the bottom of the box. Was able to use the wall cavity where the original PWM controller was located.

This was a big step in the project, now the rest should all fall into place. I figure a 12v smoke test in about a week. 120v will take a bit longer, but I want to get the 12v side operating!
 
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