My 40ft 5th wheel 1020 Watt PV Build

LanduytG

Solar Enthusiast
Well I'm basically done with all the wiring up except to pull the wire from the roof to the control panel. Using 6ga marine grade wire for that. Tidy up some with zip ties and mount the Touch 50 screen up in the living area.

I did take 2 of the PV panels and leaned them up facing the sun as best I could and hooked them up in series and then ran it to the SCC. Everything works well. The most I saw was 460 watts out of the pair (Canadian Solar 255 watt)

Ran the a/c some and then only the fan. With only the fan running I had a 245 watt load with 374 watts coming in. Was nice to see everything working. Now I need to build my frame work to mount the PV's. Building the frame work with the intent of mounting an actuator to tilt then panels.

Below are a couple of clips of the monitor screen with things running.
 

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LanduytG

Solar Enthusiast
Been out all week with the 5th wheel and camped in 2 different state parks. We had electric but I wanted to see how the system preformed so we ran off the batteries. We were able to run everything as if we had electric on. Ran the microwave which really was the only big load and then only used it may be 10 minutes a day. I did have a 60 amp load at first I couldn't figure out where it was coming from. But after some head scratching I discovered I had the frig on auto so it was using ac instead of gas.
All in all I was very pleased and excited with the performance of the batteries. After 3 days I was down to 40% which was better than I figured on, we used less power than I figured on. The 4th day I wanted to charge them up before leaving. At 120 amp charge it took a few hours to get them back to 100% but that was to be expected.
Now to get the panels mounted and hooked up. Although they would not have made any contribution this trip because we were in a park where almost all sights were well shaded.
Almost forgot. One thing I noticed is battery temp is about 10-15 degrees warmer than ambient. Like this morning its 34 degrees outside and the batteries are 48 degrees.


Greg
 
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HRTKD

Boondocker
60 amps to run the fridge on AC. Yikes!

I looked at the placard on my gas/AC fridge and it says 2.7 amps. Do you have a compressor in your fridge?
 

LanduytG

Solar Enthusiast
60 amps to run the fridge on AC. Yikes!

I looked at the placard on my gas/AC fridge and it says 2.7 amps. Do you have a compressor in your fridge?
Yes if I recall the heating element is 300 watts. So thats about 25 amps DC. On gas it only draws about 1 amp or a bit more. If the camper wasn't new I would replace the cooling unit with a DC compressor. They are really low current draw and do a better job plus the cycle off and on and would not use that much energy.

Just looked up the heating element and its 325 watts

Greg
 
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LanduytG

Solar Enthusiast
Still have the camper out to. Lean it up after our outing this week.
Measured the frig current. On DC it draws 2.4 amps if the condenser cooling fan comes on it adds another 1 amp. Now when you switch it to run off ac from the inverter its 32 amps. This is using my Fluke current clamp.
When on gas the current hog is the control unit. The gas selinoide only draws .7 amps.

Greg
 

Hedges

Photon Sorcerer
Still have the camper out to. Lean it up after our outing this week.
Measured the frig current. On DC it draws 2.4 amps if the condenser cooling fan comes on it adds another 1 amp. Now when you switch it to run off ac from the inverter its 32 amps. This is using my Fluke current clamp.
When on gas the current hog is the control unit. The gas selinoide only draws .7 amps.

Greg

0.7A at 12V?

I like millivolt thermostats. All my gas appliances other than furnace use a Peltier thermo-electric stack to power a solenoid that keeps gas valve open when pilot is lit, and operates thermostat.

0.7A or between 15 and 20 Ah/day is an absurdly high drain for a propane powered refrigerator. 240 Wh/day, about 25% of an electric compressor fridge.
 

LanduytG

Solar Enthusiast
The .7 amps is to hold the gas valve open. In the last 30 I've had 4 campers with gas frig and they all worked the same.

Greg
 

Sojourner1

Itinerant
LandutyG to give an idea on consumption here is a usual day from spring till fall when I'll start switching the fridge over to electric (Norcold 821). Our solar is close in size but your battery bank is 2x larger. You can see the batteries being charged some and solar carrying the inverter loads.
Screenshot_20201017-152900_Excel.jpg
Screenshot_20201017-152947_Excel.jpg

Here are #s from production during this period.
Screenshot_20201017-153258_Excel.jpg

I'm sure once you get the solar going you'll be a happy camper. ;)

Your setup looks great.
 

LanduytG

Solar Enthusiast
Had a very productive day. Pulled the 6ga wire going to the roof from the control center to the point where its going up to the roof. Also pulled a pair of 10ga wires for 12v for future use. Also ran HDMI and USB extension cables and mounted the Touch 50 in the coach. Now all that is left is get the wire to the roof which most likely will not be till spring but will see what weather does and time available. Used duplex marine grade wire for the PV panels. Even though its fine stranded it was kind of hard to maneuver around but we got it there.
When the breakers come in I'll get those wired in and will be ready when PV's get mounted.
Looked at some UNI Strut while in Home Depot today to make the PV mounts. Still waffling on what direction I'm going with the mounts.

Greg
 

willo

Solar Enthusiast
I used the half height unistrut to mount mine. I created a pivot using unistrut angle mounts and bolts and drilling through the side of the panel frames. Pivots went along the outer edge of the roof. In the first version I bolted three panels together - this sucked and after that I put two brackets on the inner side of the panel (toward the center of the roof.
I'm pretty happy with it, but I did mount the unistrut flat to my roof.

If I did it again? I'd grab a some HDPE or a HDPE cutting board and cut spacer blocks. Then I have a half inch between the blocks and the strut to allow water to flow under. As it is, I'm going to run some eternabond tape along the high side of the strut to create a water channel that'll direct water flow away from the rooftop penetration points.

Note: When I say mine, I mean my 37 foot 5th wheel - It's a 2020 Montana High Country 330RL
 

LanduytG

Solar Enthusiast
I used the half height unistrut to mount mine. I created a pivot using unistrut angle mounts and bolts and drilling through the side of the panel frames. Pivots went along the outer edge of the roof. In the first version I bolted three panels together - this sucked and after that I put two brackets on the inner side of the panel (toward the center of the roof.
I'm pretty happy with it, but I did mount the unistrut flat to my roof.

If I did it again? I'd grab a some HDPE or a HDPE cutting board and cut spacer blocks. Then I have a half inch between the blocks and the strut to allow water to flow under. As it is, I'm going to run some eternabond tape along the high side of the strut to create a water channel that'll direct water flow away from the rooftop penetration points.

Note: When I say mine, I mean my 37 foot 5th wheel - It's a 2020 Montana High Country 330RL
Thanks for the suggestion. I think I'm going to use Uni-Strut but because of the crown of the roof I will have to use full height. Like the tip on the spacers I will have to remember to do that when I mount them.

Greg
 

willo

Solar Enthusiast
Also... I put down self leveling sealant before I bolted in each lag bolt, then I covered the heads completely with sealant.
I've also seen some people put down a piece of eternabond between the unistrut ends and the EPDM roof.
 

LanduytG

Solar Enthusiast
Also... I put down self leveling sealant before I bolted in each lag bolt, then I covered the heads completely with sealant.
I've also seen some people put down a piece of eternabond between the unistrut ends and the EPDM roof.

I will be sure to seal it up well. Only one thing worse than a leak is the wife blowing a gasket.

Been looking and all types of things available for uni strut. End caps, channel covers etc. You can even get it in high profile and 316 stainless.


Greg
 

willo

Solar Enthusiast
I actually considered using extruded aluminum rails, but in the end I just used the unistrut. Keep it simple.
I found the best prices to be lowes for the angles, I bought bolt packs from the hardware section and simple angle brackets. The HD ones have magnets and cost more.
 

Hedges

Photon Sorcerer
Unistrut does have aluminum rails and stainless hardware, but not as readily available or cheap. They've also gotten into the PV hardware game.
I used to use hot-dipped galvanized but that isn't at the home improvement stores anymore.
Hot-dipped should stay rust-free for 20 years, thin electro-galvanized about 5 years.

Often, strut slot nuts in stock are the kind with springs. The manufacturing process was to crimp metal to hold the spring, but 1/2-13 threads were deformed to the point I can't assemble without it galling and seizing. Have to clean the up with a tap before use.

I've been using the unistrut (or other brands) for inverter mounts. My PV mounts are Unirac rails and galvanized conduit.
You'll find Unirac on eBay and elsewhere. The rails used to accept both top clamp and bottom attach clips. Catalog now says bottom clips (hook on rail, bolt to holes on PV panel frame) are only for their heavy duty rails. I see pictures of light/medium duty rails both with and without side slots for those hooks. Can't always be sure vendor is giving a photo of their actual inventory rather than just a "file photo"

Picture shows no small side slots, so for top clamp only:


One picture shows single small side slot, another shows two; that's where bottom clips go.


I'd rather panels had bolts through holes in frame, not just a clamp on top of frame, especially for mobile applications.
All mine are bottom clip now, on ground mounts. Had to adjust rails as I installed so they aligned. If I put on a roof it would get top clamp due to accessibility, also the flexibility that rails can be positioned on rafters first, panels mounted later.
 

LanduytG

Solar Enthusiast
Got up 9n the roof today and figured out where I'm going to mount the panels and how. Also hooked up 2 panels in series and had 410 watts being produced st around 7-8 Amos. After mppt is was about 30 amps. When I laid them flat it went to 250 watts. So tilting is worth it. Dont have enough real estate to make up the differance.

Greg
 

Sojourner1

Itinerant
Nothing wrong having the option to tilt especially in the winter with short days and low arcing sun. Just watch the strong winds.
 

willo

Solar Enthusiast
IMO Tilting is worth it for something like 4+ days off grid. Consider the wear factor of walking on an epdm roof too often.
 
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