Roof solar planning - cutting the hole

[camper101]

I'm thinking of adding roof solar for permanent/always-deployed solar. Wondering if you would mind taking a look at my thought process and letting me know what you think?

Right now I'm in the thinking-it-through stage -- very preliminary.

The idea is to glue panels to the top (I'm not worried about the heat/efficiency loss, as solar is most important for me in winter temps and the panels should be more than enough).

So I'm guessing the process would be something like:

1. Remove the lifting board from the ceiling
2. (Make sure I'm pre-wired... I'm pretty sure I am because of yellow/black wires behind lifting panel)
3. (Remove any insulation or whatever else is in the way?)
4. Drill a small drill bit up and out so I know where the hole will be in the roof
5. Drill a larger (3/4 inch?) hole from outside to the inside so it's a cleaner cut on the roof
6. Glue down the panel
7. Connect the wires

I think I'd want to use some kind of plug like this, which I assume I'd install with an adhesive/sealant like Silaprene(?). (Anybody know what I'd call that kind of plug or where to get one?)

The pictures below are helping me visualize and may show what/where I'm thinking.

I don't know much about panels, but I've seen 90 watt Global Solar panels like Jonathan Hanson's JATAC has (I'd just do 1 since I've got a portable setup, which I would probably downgrade if I had a permanent setup). Not cheap, but it would be worth it to me to have the low profile and minimize holes in the roof. To be honest, the only reason I considered them is I figured if they're good enough for Jonathan (seems like the kind of guy who takes this stuff seriously...) they'll work for me. Otherwise I'm just looking at Amazon reviews and most of those people seem to have had their panels for just a few weeks -- I don't want to glue something to the roof unless it'll last.

Where I think I'd drill through the roof (behind/above the wooden bar):


Roughly where I think the hole would come out (anybody know if there's something in the way there?) My panel would probably go on the passenger side since my vent is not centered:


Why I think I'm pre-wired:

I'm pretty sure I know where those wires terminate (behind a little wooden block in my Shell) but I haven't unscrewed the block or tested any current running through there yet.

Thank you for any thoughts you have!

 

[billharr]

I see you have composite lift panels. 99.99% you are prewired. I would put in a call to FWC and ask where the solar wire terminate. This will save you a lot of time. The plug in the roof is an sae plug this is what FWC installs if you order it. They will sell you one at a reasonal price. I added one to each side of my camper build.

 

[camper101]

Good to know about going through the plates. I'll definitely get with Brenda before I do anything - so far I'm trying to figure out if it's even something I want to get into (and I think I do...).

They are indeed SAE - thank you. Looks like Jonathan got some fancy 90 degree (and white) plugs somehow. I'll ask him about those.

Thanks again.

 

[billharr]

Post up where to get the 90 degree sae plugs, I have never seen them before and can not find them.

 

[4llamas]

Camper101, I am interested in knowing the measurements Brenda gives you to drill for your wiring plug. Here is what I got from her last week.

"[SIZE=11pt]Do you see anything marked with an X where the wires are? If not the information on your build sheet is 22 ¾” from the left side and 54 7/8” from the front-IMPORTANT I was told that you may need to add a ¼” to each measurement.[/SIZE]
[SIZE=11pt] [/SIZE]
[SIZE=11pt]I hope yours has the X.[/SIZE]

Brenda[SIZE=11pt]"[/SIZE]

Mostly I'm curious if they are all about the same location. My camper is a 2009 Hawk. [SIZE=11pt]I don't have an X and I don't know how I would know to add 1/4". I'll drill a hole just big enough to fish around in. [/SIZE]

[SIZE=11pt]Those plugs do look good. [/SIZE]

 

[Fyreman]

Second that on the 90° plugs. I would like to know too

 

[Bwht4x4]

I have a late 2013 Hawk that I ordered without a solar plug on the roof. When I took it up to FWC to have one installed all they did was remove the long narrow wood lift piece to access the junction box. From there they simply drilled a hole upward through the roof and mounted the SAE plug and goobered it up with a lot of sealant. They then connected the wires from the SAE plug to the wires that were already in the junction box from the original build that terminated in my battery box. Once they did that it was super simple to install the MPPT controller connect to the battery.

 

[4llamas]

That sounds like a good approach. It would take the stress and guess work out of drilling a hole in the roof. I might be wrong , but I think my wires terminate at the battery isolator. Not a big deal. Thanks for that information.

 

[Bwht4x4]

Isn't your battery isolator and batteries in the same compartment? My wires were in this compartment with butt connectors crimped on to them for protection. They were wrapped up tightly right next to the battery separator. To get better access to them I had to remove the protection around the isolator and then reinstall it afterwards.

 

[billharr]

Sounds easy to see if you are pre-wired. Just look in the battery box and see if you have a set of rolled up wires. Mine were marked solar.

 

[GCS03]

[SIZE=10pt]I have a 2014 Hawk, on a 2006 Tundra, with the 90w solar panel on the roof, two batteries, etc. Problem: I ordered the three-way refrigerator that appears to draw 176w when it’s on DC (12v, 14.6A). Great refrigerator and made ice for tea everyday... But, public school math tells me a 90w panel won’t do me a lot of good. Was hoping to primarily use solar during the day and propane at night. Questions for the group:[/SIZE]

[SIZE=10pt]1. Why would FWC sell me a refer that draws 176w without recommending a 200w panel or two of the 90w? [/SIZE]

[SIZE=10pt]2. Can I just remove and replace the 90w with a 200w? [/SIZE]

[SIZE=10pt]3. My Tundra, with HO 150A alternator, does not charge my two new FWC placed batteries even when going down the road during bright sunlight? Seems like it should. Is the 90w draw on the refer just too great for the Tundra or do I need to get something checked? [/SIZE]
[SIZE=10pt]Love the FWC and the refer. Best purchase in years! Fix this issue and it’s perfect!![/SIZE]

[SIZE=10pt]Thanks for any ideas...[/SIZE]

 

[billharr]

I think everyone will agree that a 3 way fridge on 12v will just (barely) maintain temp. You will not cool down on 12v. Propane will work but remember you have an absorption fridge no matter if 12v, 110v or propane. You will see a 40 to 50 degree drop from ambient temp. Your money will be better spent on a DC compressor fridge than a bigger panel. Also going to a bigger wire from your truck will help with the charging. Put a voltage gage in your camper to make sure you are charging from your Tundra.

 

[camper101]

Thanks again all, Bwht4x4 that's good to hear - I'm hoping it'll be that easy for me to do myself. So the SAE plugs just stick straight up? It's probably only an inch or two, but if you have a picture handy I'd love to see it.

I heard back from Jonathan on the 90 degree SAE plugs. He got them through (perhaps installed by?) Tom Hanagan. Apparently Tom does not have more, but he knows the source - but they require a "huge" minimum order.

4llamas: I'll follow up and let you know about any "X" although I'm moving somewhat slow on this project so it may be a while before I remove the lifting board. I'll reply to this thread though. Again, my hope is that it's just like Bwht4x4 described.

FYI if anybody was wondering I got a shell and subsequently had a battery installed by the local FWC guy. From what I understand the wires terminate behind the wall (there's a little wooden block that all the other wires come out of, and the solar pre-wire should be in that neighborhood).

 

[craig333]

Basically your three way fridge is only intended to use 12v mode in a very temporary fashion. While you're driving and maybe some shorts stops. Its not meant to used in camp. They sip propane so its not really an issue to use it during the day too.

 

[camper101]

OK another question comes to mind: when you plug in the panel, do you seal it at the plug (not where the outlet is installed on the roof -- I mean where the plug from the solar panel actually goes into the outlet)?

I realize those plugs are used on plenty of trailers and other places with moisture, and I assume that not much water gets in there, but I'd have to have a roof leak of any kind.

 

[4llamas]

4llamas: I'll follow up and let you know about any "X" although I'm moving somewhat slow on this project so it may be a while before I remove the lifting board. I'll reply to this thread though. Again, my hope is that it's just like Bwht4x4 described.

Thanks, but don't worry about it. I think Bwht4x4 described the best approach.

 

[4llamas]

Isn't your battery isolator and batteries in the same compartment?

No. On my 2009 Hawk they are on opposite sides of the camper.

 

[Bwht4x4]

I am no expert on all years of FWC and can only speak to my 2013 set up. I'll help/assist where I can but it will be what I know from my 2013 year model.

 

[GCS03]

[SIZE=10pt]Bill, I read the same comments with the three-way and was a little concerned until we tried this unit. Maybe there are better setups, I’m sure there are. But, this unit kept everything cold or frozen, and made two trays of ice for us every day for two weeks (night time on propane). It was in the mid to upper 80s most of the days. We used propane after dark and solar/propane during the day (using the middle setting on the fridge) and only used ½ tank of propane (including heating water, etc.). I was just hoping to use less propane and more solar. But could have enough for 4 - 6 more weeks. I have then extra solar plug, so could always add a portable panel versus changing out the roof panel or adding an additional panel. [/SIZE]

[SIZE=10pt]“Also going to a bigger wire from your truck will help with the charging.” From the truck to the camper plug? [/SIZE]

[SIZE=10pt]“Put a voltage guage in your camper to make sure you are charging from your Tundra.” Any suggestions on this? At the battery? Sorry, new to this stuff... [/SIZE]

[SIZE=10pt]Mr. Mumbles, maybe I should drive less and park more? [/SIZE]

[SIZE=10pt]Thanks for the help and suggestions.[/SIZE]

 

[billharr]

[SIZE=10pt]“Also going to a bigger wire from your truck will help with the charging.” From the truck to the camper plug? [/SIZE]
[SIZE=10pt]Yes the larger the wire the less voltage drop.[/SIZE]

[SIZE=10pt]“Put a voltage guage in your camper to make sure you are charging from your Tundra.” Any suggestions on this? At the battery? Sorry, new to this stuff...[/SIZE]
[SIZE=10pt]Look at this thread for information on a voltage meter. Search is your friend on WTW there is a lot of information on just about any thing you need.[/SIZE]

[SIZE=10pt]Bill Harr[/SIZE]

[SIZE=10pt]Thanks for the help and suggestions.[/SIZE]