|
08-19-2021, 01:34 PM
|
#1
|
Winnebago Owner
Join Date: Aug 2020
Posts: 184
|
Solar Wiring Access
Since I want the option of storing my motorhome after the winter in Palm Springs, I've decided to install 1-2 panels for battery maintenance (and potential future boondocking). I had planned to install with all new wiring, but noticing a solar circuit under the steps, I've been trying to track down where any existing wiring might be. There is absolutely no junction box on the roof, so I'm doubting that there is an option here.
I also wonder if there is a wiring chase from the roof. How do people get 8-10 AWG wire from the panels down under the chassis? Drill a hole above the refrigerator and route behind? Do the AC units have a chase I could "hitchhike" in?
__________________
2002 Winnebago Brave (WPF32V)
Workhorse P32
S/N 10F71C261406
|
|
|
08-19-2021, 07:08 PM
|
#2
|
Site Team
Join Date: Sep 2009
Location: Spring Branch, TX
Posts: 7,780
|
One a 2002 Brave there "may" be a 10 watt panel on the roof connected to the Chassis battery as a maintainer. But never think of it as a "solar charging system." Those never even had a solar charge controller. They didn't need one because they were practically worthless as solar power providers.
It was a gimmick RVs did 20 years ago to be able to say they have solar.
None of that system is capable of upgrading or being used instead of running new wiring and adding "real" solar panels.
__________________
2017 Winnebago Adventurer 37F
2016 Lincoln MKX Toad
|
|
|
08-19-2021, 07:19 PM
|
#3
|
Winnebago Owner
Join Date: Aug 2020
Posts: 184
|
Nope. Nothing on the roof. Just the evidence of a circuit labeled "solar," under the steps. If there was a junction box on the roof, I'd test the resistance of the wires and be tempted to use them, but no joy.
So my main question is: What's the best (easiest) way to get wires down from the roof? I still suspect that behind the fridge is the ticket, but perhaps someone has found a better way...
__________________
2002 Winnebago Brave (WPF32V)
Workhorse P32
S/N 10F71C261406
|
|
|
08-23-2021, 10:52 AM
|
#4
|
Winnebago Master
Join Date: Oct 2017
Location: Elk Grove, CA
Posts: 3,573
|
If your's is anything like mine, with the batteries under the entry steps, the refrigerator compartment is the easiest route to the batteries. The simplest way is to just run the wires into the refrigerator vent and not make any more holes in your roof. Just make sure the wires are secured so they don't contact anything hot. If you do decide to go through the roof, you should use something like this:
https://www.amazon.com/Waterproof-Re...dp/B07W3PPH1S/
Creativepart is correct, there is nothing reusable from your existing solar panel wiring. If I recall, it's only 14 gauge, which is way too small. You'll need 10 gauge at a minimum (smaller number, larger wire diameter). There are numerous sites with online calculators that will assist you in selecting the appropriate wire gauge. The calculation is based on amps, wire length and acceptable % voltage loss. It's better to go with a larger wire size than necessary in order to allow for adding additional panels.
The same goes for choosing a controller in that it's best to allow for growth.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
|
|
|
08-23-2021, 11:25 AM
|
#5
|
Winnebago Owner
Join Date: Aug 2020
Posts: 184
|
Thanks for the input! I've done decades of boat wiring and electrical component sizing, but routing the wires from the roof was not intuitively obvious. I suspected the space behind the fridge was the answer. Now I just have to figure out the best way to attach the panels. Solar is considerably more efficient when you leave an air space under them for heat dissipation.
__________________
2002 Winnebago Brave (WPF32V)
Workhorse P32
S/N 10F71C261406
|
|
|
08-23-2021, 12:20 PM
|
#6
|
Winnebago Master
Join Date: Oct 2017
Location: Elk Grove, CA
Posts: 3,573
|
On my 2002, the thin Filon fiberglass roof is not uniformly secured to the underlying 1/8" luan plywood. Therefore, my plan is:
1. Make my own mounts out of 1.5" aluminum angle stock, 8" long. I'll use four per panel, two at the front, two at the rear. They provide more mounting surface than most commercially available mounts. 8" is probably overkill, 4" should be adequate.
2. I'll angle them so as to accommodate the curve of the roof. Initially I'll only mount them to the panel with one screw so I can add the second after mounting to the roof so I get the roof angle right.
3. I'll mount them with both 3m VHB tape and screws just to be safe. With a total of 1.5" x 8" x 4 = 48" of mounting surface per panel, the VHB tape is probably adequate but I don't trust the adhesion of the fiberglass to the plywood. Similarly, being only 1/8" thick, I don't trust screws alone.
I used this the same process with VHB only to mount a 100W panel to my relatively thick fiberglass van top and it's as solid as a rock. You can see the angle. The panel is mounted to a 20" wide crown in my van top. Rather than buy wider VHB tape I bought a roll of 1" wide tape and have found all sorts of uses for it. This is what I bought:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Note: The 3m data sheet lists the tensile strength (pulling things straight apart with no sheer) at 140# per square inch so, with 48 sq in/panel. I figure I have a pretty large safety margin.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
|
|
|
08-23-2021, 12:37 PM
|
#7
|
Winnebago Owner
Join Date: Aug 2020
Posts: 184
|
That's a very effective solution. Whatever bracket I come up with, I'm thinking about well-nuts for the blind-fastener portion of the attachment. I'm also fond of the double-sided foam tape (if it's good enough to attach semi fenders, it's good enough for ME). Another option would be 3M 5200.
__________________
2002 Winnebago Brave (WPF32V)
Workhorse P32
S/N 10F71C261406
|
|
|
08-23-2021, 12:55 PM
|
#8
|
Winnebago Master
Join Date: Oct 2017
Location: Elk Grove, CA
Posts: 3,573
|
Quote:
Originally Posted by MadMaxWinny
That's a very effective solution. Whatever bracket I come up with, I'm thinking about well-nuts for the blind-fastener portion of the attachment. I'm also fond of the double-sided foam tape (if it's good enough to attach semi fenders, it's good enough for ME). Another option would be 3M 5200.
|
Well nuts are probably a good idea. One advantage of the VHB tape over 5200 is that it will be easier to remove if necessary. You can cut through it with a thin piece of wire like a guitar string or piano wire.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
|
|
|
08-23-2021, 01:00 PM
|
#9
|
Winnebago Owner
Join Date: Aug 2020
Posts: 184
|
Quote:
Originally Posted by BobC
Well nuts are probably a good idea. One advantage of the VHB tape over 5200 is that it will be easier to remove if necessary. You can cut through it with a thin piece of wire like a guitar string or piano wire.
|
Indeed. The 5200 takes a fine saw blade and a lot of patience + some cosmetic repair.
__________________
2002 Winnebago Brave (WPF32V)
Workhorse P32
S/N 10F71C261406
|
|
|
08-25-2021, 04:29 PM
|
#10
|
Winnebago Owner
Join Date: Aug 2020
Posts: 184
|
BobC was right on the money! I removed the four (very rusted) bolts on the fridge vent, and low and behold, I can shine a flashlight all of the way to the coach floor. From there, it's a five foot run behind the stove to a wire chase into the basement. The 8/2 conductor wire will easily route this way without putting another hole in the roof. Thanks, Bob!
__________________
2002 Winnebago Brave (WPF32V)
Workhorse P32
S/N 10F71C261406
|
|
|
08-25-2021, 04:48 PM
|
#11
|
Winnebago Camper
Join Date: Aug 2018
Location: Brooksville, FL
Posts: 32
|
I have 200 watts of solar panels on the roof of our 2004 Adventurer. The wires went down the refrigerator vent, as was suggested previously. That works really well.
I bought my panels and wiring and controller from Windy Nation in Ventura, Ca. The panels came with mounting brackets that raise tge panels above the roof allowing air and rain flow underneath. Mounted the brackets to the panels and positioned the panels in place. Marked the bracket locations on the roof. Then put Dicor on the bracket marks, put the panels in place and screwed them down through the Dicor the covered thebracet foot and screw with more Dicor.
|
|
|
08-25-2021, 05:03 PM
|
#12
|
Winnebago Master
Join Date: Oct 2017
Location: Elk Grove, CA
Posts: 3,573
|
Quote:
Originally Posted by MadMaxWinny
BobC was right on the money! I removed the four (very rusted) bolts on the fridge vent, and low and behold, I can shine a flashlight all of the way to the coach floor. From there, it's a five foot run behind the stove to a wire chase into the basement. The 8/2 conductor wire will easily route this way without putting another hole in the roof. Thanks, Bob!
|
You're welcome, it's always nice to hear that our advice was on the money.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
|
|
|
08-25-2021, 05:05 PM
|
#13
|
Winnebago Master
Join Date: Oct 2017
Location: Elk Grove, CA
Posts: 3,573
|
I've had good luck ordering panels from both Home Depot and Amazon. Two 160W Grape Solar panels from HD a couple of years ago and two 100W Renogy panels from Amazon this year.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
|
|
|
09-08-2021, 04:59 PM
|
#14
|
Winnebago Owner
Join Date: Aug 2020
Posts: 184
|
Happy ending: Installation complete. My only mistake was getting a controller which I felt funny about (I had a 40% discount from an old contact). It performed flawlessly for four days, and then died. You get what you pay for.
Replacing with a proper Victron MPPT controller this afternoon. Like my spiffy new marine polyurethane epoxy paint job? I mean, while I was UP there...
Thanks for all of the input!
__________________
2002 Winnebago Brave (WPF32V)
Workhorse P32
S/N 10F71C261406
|
|
|
09-08-2021, 06:03 PM
|
#15
|
Winnebago Master
Join Date: Oct 2017
Location: Elk Grove, CA
Posts: 3,573
|
Congratulations. Don't forget to give us an update on its performance.
__________________
Bob C
2002 Itasca Suncruiser 35U
Workhorse Chassis
|
|
|
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|
|
|