Solar Installation on 19

[rubicon327]

After considerable research and reviewing installations by others on the forum I have finally decided to install a solar system. Without a rooftop A/C and fridge vent on the roof it is easier to coordinate the fitment of several large panels. If I'm going to do this I want to maximize my wattage within reason and have long term durability. My current concept includes three 200W 24V panels by Rich Solar. These will be wired in parallel to an AM Solar combiner box which will then have a feed into the trailer to a 50A Victron 100/50 solar controller. The panels will be mounted with AM Solar Rocker Foot mounts utilizing VHB which they do routinely. The feet will need varying heights due the changes in height of the "tunnel" down the middle of the trailer. Since this is an early Gen1 trailer I'm also contending with the rooftop A/C reinforcement "cap" that was used before the molds were changed to make the roof stronger. The panels are dimensioned such that my mounts are wide enough so that I can bolt through the shell into the upper cabinets if I want to now or in the future. The rocker mounts allow for tilting towards the front or rear of the trailer with the use of tilting kits that I will likely modify for multiple angles. The installation will be very similar to the picture attached of a trailer done by AM Solar but with an additional panel in the middle. I will be tilting the front panel down in the front as much as possible to reduce wind load. I'm also considering adding a fairing to deflect the wind utilizing fairing mounts by Redarc that will be adhered to the shell and sit along the front edge of the panel. I will also include a sidewall port to allow a portable to be plugged in to supplement the rooftop panels in variable conditions. Since I will have all of the panels paralleled on one solar controller I must match the 37.6 Vmpp of the rooftop panels as close as possible so I found a 24V portable made by Lion Energy with a Vmpp of 35V.

There will also be a shut off switch on the positive wire between the combiner box and solar controller and a 60A circuit breaker between the controller and the battery.
https://amsolar.com/wp-content/uploa...110_RS2001.pdf

Any thoughts would be appreciated before I start the install.

[HABBERDABBER]

About the only 2 things I'd offer are that the wind fairings are a very good idea to eliminate the airfoil effect of the front panel and my preference for mechanical fastening over adhesives. I use adhesives all the time, tapes, films and was epoxying a wood project today. But adhesives can have a shorter lifespan than a nut and a bolt and be affected more by outdoor exposure and conditions.

Guess I'm a "belt & suspenders" mentality.

Just a thought: What if you used some telltales like those on sails to see if airflow on your other panels would suggest wind fairings there. A GoPro camera attached to a vent to record telltail behavior when at travel speed.

https://www.precisionsailloft.com/bl...nterpret-them/

[MVA]

Two thoughts....

From an aerodynamic and frontal load, I would ensure the front panel is well secured. I believe that GoPower used to require two feet from the front of the trailer to the leading edge of the panel. I have no idea what their technical basis was for this engineering judgement. For a 200W rear panel, we used 3M VHB tape and stainless steel hardware to secure the solar panel to the trailer. We also used blocking to distribute the load on the inside of the fiberglass shell.

From a electrical wiring standpoint, we ran the wires on the roof through a waterproof clamshell down the wall space between the bathroom and the D/S dinette. If you remove the medicine cabinet, you can gain access to this space easily. Our wiring ran down that wall space and exited at the D/S dinette bench. Of course, this depends where you plan to locate batteries and electrical equipment.

Enjoy. Nice spring project!

[Centex]

Looks like a great plan.

I really like the looks of those Rich panels, wonderful specs and slightly smaller than the Grape Solar GS-Star-200W I bought from AMS several years ago. Admitting a touch of envy there.

I'm curious about the detail for managing the 'cable slack' needed to accommodate panel tilting. Does AMS typically just leave a 'loop' of the 10ga duplex cable laying loose on the roof under each panel between the anchor points on the panel and roof?

Another detail question .... do you plan to transition from the panel MC4 connectors to the 10ga duplex using their MC4 connector 'pigtails', or by cutting the MC4 connectors off of the panel wires and making an inline crimp connection? I know they offer bits for either method, just curious what your thoughts are about that choice.

[Centex]

Around the time of my solar scheming there were several anecdotes of 'panel failures' on this forum. I agonized over that and spent much time dreaming up reinforcing for the long-side of panels (I was convinced that long-side buckling was at the root of the problem and that cascaded to other effects). Many of those schemes were quite a bit of overkill I suspect, and who knows of any such reinforcement is really necessary at all (AMS' long experience suggests not)?

Anyway, sharing FYI what I settled on just for a bit of peace of mind, hopefully the pics are sufficient to explain. The reinforcement I added inside the Grape Solar panel frames is bolted through the AMS Rocker Mount holes at each end and at 3 points along the length between each end.

[rubicon327]

Originally Posted by MVA

Two thoughts....

From an aerodynamic and frontal load, I would ensure the front panel is well secured. I believe that GoPower used to require two feet from the front of the trailer to the leading edge of the panel. I have no idea what their technical basis was for this engineering judgement. For a 200W rear panel, we used 3M VHB tape and stainless steel hardware to secure the solar panel to the trailer. We also used blocking to distribute the load on the inside of the fiberglass shell.

From a electrical wiring standpoint, we ran the wires on the roof through a waterproof clamshell down the wall space between the bathroom and the D/S dinette. If you remove the medicine cabinet, you can gain access to this space easily. Our wiring ran down that wall space and exited at the D/S dinette bench. Of course, this depends where you plan to locate batteries and electrical equipment.

Enjoy. Nice spring project!

Thanks for the insight. My lithium battery is in the front passengers side dinette so I plan to drop in under the front panel as shown in my sketch. Also the early trailers do not have a medicine cabinet for access in the bathroom. The AM Solar combiner box is designed to be shallow in height so it can reside under a panel. My hope is that puts me right in the upper cabinet and then I can take my wiring down the front corner and have my solar controller mounted right next to the battery.

[rubicon327]

Originally Posted by Centex

Around the time of my solar scheming there were several anecdotes of 'panel failures' on this forum. I agonized over that and spent much time dreaming up reinforcing for the long-side of panels (I was convinced that long-side buckling was at the root of the problem and that cascaded to other effects). Many of those schemes were quite a bit of overkill I suspect, and who knows of any such reinforcement is really necessary at all (AMS' long experience suggests not)?

Anyway, sharing FYI what I settled on just for a bit of peace of mind, hopefully the pics are sufficient to explain. The reinforcement I added inside the Grape Solar panel frames is bolted through the AMS Rocker Mount holes at each end and at 3 points along the length between each end.

Thanks! I was planning to reinforce the long side of the front panel but figured I would get the panels in hand before thinking about it too much. They are on their way as I recently got the drop ship notice from AM Solar.

[rubicon327]

Originally Posted by Centex

I'm curious about the detail for managing the 'cable slack' needed to accommodate panel tilting. Does AMS typically just leave a 'loop' of the 10ga duplex cable laying loose on the roof under each panel between the anchor points on the panel and roof?

This was something I planned to figure out once I got the panels up on the roof but the attached photo from AM Solar gives a good perspective on how they do it.

Originally Posted by Centex

Another detail question .... do you plan to transition from the panel MC4 connectors to the 10ga duplex using their MC4 connector 'pigtails', or by cutting the MC4 connectors off of the panel wires and making an inline crimp connection? I know they offer bits for either method, just curious what your thoughts are about that choice.

Plan on using the MC4 connector pigtails provided by AM Solar. I want a convenient way to remove the panel if that is ever necessary.
https://amsolar.com/shop/roof-cable-...4/93c-mc-4pig/

[Centex]

Originally Posted by rubicon327

This was something I planned to figure out once I got the panels up on the roof but the attached photo from AM Solar gives a good perspective on how they do it.

Originally Posted by rubicon327

Plan on using the MC4 connector pigtails provided by AM Solar. I want a convenient way to remove the panel if that is ever necessary.
https://amsolar.com/shop/roof-cable-...4/93c-mc-4pig/

[brroberts]

I’ve been pondering panel reinforcement also. I want to put one big panel on the rear of the trailer and move the 190 GoPower to my observatory. I wonder about air pressure when the panel extends beyond the roof a few inches to the rear. I won’t remove the fridge vent as John did to create additional space.

[MVA]

This is how we reinforced the long side of a 200W panel. Aluminum 1/8" L channel is bolted through the existing holes in the panel. Unfortunately, the panel is fixed and does not tilt; one of rubican327's requirements.

[rubicon327]

Originally Posted by MVA

Unfortunately, the panel is fixed and does not tilt; one of rubican327's requirements.

I’m only tilting because the trailer usually spends a month or so near Erie PA in November as a steelhead fishing basecamp. Optimum tilt at that time of year for that latitude is about 50-55 degrees. Between that and the overcast weather I figured that flat panels wouldn’t have a prayer at producing much and the tilt will also help to shed any snow. Would be really nice if we didn’t need to pull the generator out at all!

…and I realize that I could have some partial shading of each other with all the panels tilted in the configuration I have but I figured that the output of two panels tilted and the middle one flat is still better than all of them flat. With them all wired in parallel this variable output per panel should be ok and will still maximize the energy production based on my understanding.

[Doug & Betty]

All good thoughts and suggestions. I did a very similar installation on our 19 and found the best place to mount the AM Solar combiner box was near the bathroom vent. If you pull the medicine cabinet, you’ll find lots of access to the roof looking up, and looking down you’ll find an easy access to the area under the DS seat where all the electrical stuff is. I spaced a piece of plywood over the black water tank box in order to minimize the chance I would run a screw into it and also fastened another panel to some of the seat support to hold the various components. It made the interior wiring very easy. Everything was well sealed with Proflex and I have no issues in 7 years.

Enjoy the mod!
Doug

[Doug & Betty]

Hi Steve, I sent a reply to your PM but don't see it anywhere. Let me know if you received it or not please. If not I'll try it again. Doug

[Centex]

Originally Posted by rubicon327

.... My current concept includes three 200W 24V panels by Rich Solar. ....

As I understand, the 24V (nominal) panels offer two advantages over 12V (nominal) panels in a 12 volt system with an MPPT controller

• Lower ampacity wire required for parallel arrays
• The higher voltage offers the potential for starting MPPT controller charging (noting most Victron MPPT controllers require Battery V+5V to start charging) when solar exposure is poor (low sun angle, overcast, partial shading, etc), potentially yielding more net charging per day in those conditions than a 12V nominal panel all other things being equal.

Is that correct per your understanding? The latter is of particular interest to me.

[rubicon327]

Originally Posted by Centex

As I understand, the 24V (nominal) panels offer two advantages over 12V (nominal) panels in a 12 volt system with an MPPT controller

• Lower ampacity wire required for parallel arrays
• The higher voltage offers the potential for starting MPPT controller charging (noting most Victron MPPT controllers require Battery V+5V to start charging) when solar exposure is poor (low sun angle, overcast, partial shading, etc), potentially yielding more net charging per day in those conditions than a 12V nominal panel all other things being equal.

Is that correct per your understanding? The latter is of particular interest to me.

No real-world wire savings for me since AM Solar is conservative with the gauges they include in their kits but there might be a small savings if one got aggressive and sourced their own wire. I wouldn't want to lose the future flexibility of larger gauge wire anyway. I have 10 gauge from each panel to the combiner and 4 gauge from the combiner to the solar controller which continues on to the battery. The latter part was of more interest to me. With a Vmpp of 37.6V I should see more net charging per day as you highlighted. Charging should start earlier and go later and there should be better performance in low light conditions caused by clouds, shading, etc. I can only assume this will be more important in my part of the country with less solar irradiance than other areas like the southwest. It seems the only disadvantage of 24V panels is that they are almost non-existent in smaller wattage panels so expansion of the system becomes more challenging for some. This is not a huge concern for me because I already used up most of the roof space and found a 24V portable. If a small 24V panel is needed I did find that they are made by Newpowa that has a 30, 60 and 120W version.

Got all my stuff from AM Solar today! Just waiting on the panels to be drop shipped.

[Perry Butler]

Originally Posted by rubicon327

My current concept includes three 200W 24V panels by Rich Solar. These will be wired in parallel to an AM Solar combiner box which will then have a feed into the trailer to a 50A Victron 100/50 solar controller. The panels will be mounted with AM Solar Rocker Foot mounts utilizing VHB which they do routinely. The feet will need varying heights due the changes in height of the "tunnel" down the middle of the trailer.

I installed three 24v 200 watt Rich Solar panels last fall with a Victron 100/50 solar controller, using simple wire combiners. Last week in southern Arizona we got 560 watts at some point during the day with our panels flat, according to the history of our Victron 100/50 controller. A couple of days ago, within 5 minutes of sunrise, the panels were putting out 25 watts. We typically use 40-70 amps a day (Terry has a CPAP). The 200 ah's of LiFePO4 batteries are always full by noon, and with full sun, before 11 am.

I did tilt the panels once, but I didn't see much increase in the solar harvest. YMMV. The object in 600 watts was to not need to tilt the panels, get better solar in shade, and not need to get our portable out. In massive shade we still get 60-80 watts. We did have to get the portable out once last fall in full shade in Cumberland Gap NP, and so far just once this winter in Chiricahua NM. We dry camp/boondock as much as possible.

I used AM Solar's 5 position mounts (4 mounts per panel) glued to the roof with VHB tape. After well over 10,000 miles of the camper going down the road the panels are still there. I did sand the roof where the VHB tape now resides, cleaned up all sanded residue, and used 94% isopropyl alcohol to finish the cleaning before attaching the tape. AM Solar claims that prepping the roof is key to keeping the panels on the roof.

You will love Rich Solar's 200 watt 24v panels, the Victron 100/50, and the AM Solar mounts!

Pery

[rubicon327]

Originally Posted by Perry Butler

You will love Rich Solar's 200 watt 24v panels, the Victron 100/50, and the AM Solar mounts!

Thanks Perry. Our discussion is what convinced me that 24V panels were the way to go. Panels arrived Thursday. They are very high quality. Just need some isopropyl alcohol and I’ll have everything I need for the installation. I’ll post progress on this thread.

[John in Santa Cruz]

I have a single 360W monocrystaline panel that outputs about 36V under load, 44V open... It feeds a Victron 100/30. It's flat mounted on the back of my 21C. It can output about 2400WH a day, will generally charge my 2*12V 206AH lithiums by 11AM, or fully charge them from a deep discharge in 2 days. Those 2 batts are combined 5260 watt*hours...

[viator36]

I have been considering adding/upgrading solar panels on my 21C in conjunction with upgrading to LPF4 battery for some time. I intend to upgrade to 600W total solar capacity from my stock 170W but my trailer has the TV antenna in front of the Maxx fan so I can't use that spot unless I get rid of the antenna. I measured my trailer rear rooftop space from behind the A/C vent opening (I don't have rooftop A/C) to the back of my current panel rear edge and it has enough space to squeeze in two 200W panels. But the fridge roof vent on driver's side would be slightly in the way for one anchor support leg so I need to figure out a solution for it. The third panel will be between the two rooftop vents obviously.


I feel I know way too little about electricity and electronics to take on a project like this. But I still want to learn from the experts on here and I'll follow Dave's progress on this thread with great interest.


Btw the battery I am interested in is this Epoch 12V/460Ah battery which Will Prowse said is one of the best built on the market (

review link

).