Over the last few days, I finished my solar install and then went on an overnighter to see how they would do. I thought I would write this up for others who recognize the benefits of solar, but are only slightly of the mechanically inclined sort. In other words, just like me.
Here's what I put in:
2 Kyocera KD140GX-LFBS 140 Watt 12 Volt Solar Modules w/ MC4 connections
Blue Sky 3000i controller
Battery temp sensor
Fuse holders and covers
MC4 extension cable 30 ft
6ga wire and connectors
It has been the largest project I have done to the DesertBoat to date, both financially and in the lifestyle improvement sense. This forum has been very helpful in planning and learning from other members for installation. I especially want to thank WVvan for documenting his solar install so thoroughly. Without him, I would have been re-inventing the solar wheel. I used a lot of his methods for installing the panels to the PH. I hope he gets HAL’s motor situation fixed without too much pain.
I started with the part that worried me the most: Putting the panels on the PH roof. I put one panel up on the van, propped it up on some scrap wood, and measured, measured, and then measured some more. (Yes, I admit that I am a Nervous Nellie when it comes to drilling holes in a vehicle.) Then I cut some brackets from 2x2 aluminum angle that I thought would work.
Then I had to plan where to drill the holes in the PH roof and the solar panels, and where the holes in the brackets should be. This took me a long time, because I wanted to keep the panels low to the roof and be able to attach the brackets to the panel frames in a very small target area.
As for the holes in the PH, I wanted to drill through the wood planking embedded in the fiberglass PH top. I was worried about wind loads in excess of 75-80 mph when moving on the highway, plus even more airspeed when driving into a headwind. I figured that drilling through the planking would be better than just bracing against the thinner areas of fiberglass. More measuring!
An aside: I see a lot of pictures of PH’s on the forum that have indentations on the top of the roof. I assume they are smooth on the underside of the roof. Mine is the opposite: I have a smooth roof, and as near as I can tell, the indentations are on the underside of the roof, and most of them are hidden from view unless I remove the PH ceiling. Just thought that was odd. Maybe mine is special!
Adding to the complexity of where to drill is that I wanted all the PH roof penetrations to be outside of the canvas wall to keep leaks on the outside. I’d still need to guard against rainwater leaking into the wood planking to prevent rot inside the PH fiberglass. This is the tradeoff I had to decide on: Go for more structural strength by bolting through the wood inserts with possibility of water damage, versus a potentially weaker mount point in the thinner layers of fiberglas and not worry so much about rain. I went for strength.
I had to drill additional holes in the side of the panel frame. The factory mounting holes were on the bottom edge, and quite far in. I didn't see how I would have any room to use them without lifting the panels higher from the roof.
The inner frame of the solar panels has a flat groove area about 3/8” wide on the inside. The 1/4 x 20 nuts and star washers I was using wouldn’t fit well into the groove and wouldn’t tighten flat. I used some 1/2”x 1/8” flat aluminum stock and cut it to 3/8” wide by about 1.25” long. I then drilled 1/4” hole for the bolt to come through. When these pieces are inside the panel frame, they provide a nice flat surface for the star washer to bite into...
...which fit in this space on the inside of the panel frame.
Now with the bolt, star washer and nut in place. By the way, I used all stainless steel hardware because it is in contact with the aluminum brackets and panel frames.
In my original plan, I wanted to mount the panels as far forward as possible, almost to the front edge of the PH. I couldn’t do that because the PH roof has an odd hump near the front center area. I wanted the panels to be low to the roof, but still have the Kyocera-recommended 2” of space between the back of the array and the roof for ventilation. Because of the shape of the PH fiberglass, I ended up having to mount the panel about 8” back from the front of the PH.
After I got all the holes and brackets figured out and in place temporarily, I lifted the panels off of the driver’s side again(!) so I could make the panel wire connections, put the wires in jackets, and secure the whole mess with zip ties. I really like the MC4 connector system…connections are quick and secure, and using the Y-connectors, it eliminates having to install a junction box somewhere. I purchased one F-F-M Y-connector for the positive cable, and another M-M-F Y-connector for the negative cable.
From the Y-connectors, I used a 30 ft MC4 extension cable to make the run to the solar controller. I cut the extension cable in half, so I had two pieces of cable 15 ft long, one with a male MC4 connector, the other with a female MC4 connector, each plugging into the Y-connector. I then snugged all the cables up in corrugated sheathing and wire ties.
At this point, I had all the holes drilled in the PH, the bracket arrangements all worked out, and all the bolts, washers and star washers in finger-tight. While the panels were propped up to do the neatening of the cables, I put a loop of OSI caulking around each hole in the PH.
Then I carefully lowered the panels down again, making sure that the bracket bolt threads didn’t touch the wet caulk. After I had both sides caulked, I reattached the washers and nut and tightened all the bolts. The caulk squished out nicely and evenly from under the brackets, indicating that I had a good seal around the bolts.
Now that the panels were connected, the cables to run to the controller were hot, putting out 20V according to my multimeter. I played it safe and flattened one of the boxes the panels came in and clamped it over the panels to shade them. I also put electrical tape over the loose ends of the cables.
I drilled two 1/4” holes in the PH top, angling them outward as they went down through the internal planking. I thought the angle would put a little less stress on the cables. I also wanted to have the exposed portion of the cables protected by the panel frames so that tree branches couldn’t catch in them when off-roading.
In one of my rare moments of genius, I took the time to put strips of red electrical tape every few few feet along the positive wire so that I would know which cable was which later in the install. Doing this saved a bunch of time later as I made the connections to the controller and installed an inline fuse holder, because I didn’t have to trace the positive line back to the panels. I highly recommend doing this before snaking the cables through the PH and wherever you have to hide the cable behind panels and such.
Based on my original plan, I thought 15 ft of cable from the Y-connnectors would be plenty long enough. Turns out, it was barely enough because I had to alter my original plan as to how I ran the cables to the interior. I had wanted to drop the cables straight down and get to the back of the cabinet where the controller was going to mount by drilling through the top of the van’s factory roof, assuming that all that I had to drill though was one layer of sheet metal.
The reason I had to re-route them was because the van has a structural beam under that portion of the roof. I didn’t think I could drill through there without hitting something vital if there is anything in there to hit. There may not be anything inside that beam, but I couldn’t verify by sight or feel. I didn’t want to take the risk of damaging something that would be a nightmare to repair. In my van, there is a bundle of wires clipped to the underside of the beam.
In retrospect, I should have investigated the roof area first instead of assuming that is was just a single layer of sheet metal. If I knew then what I know now, I would have routed the cables in the space between the panels to reduce about 24” of cable run. I suppose I could still do it that way, but then I would have holes to seal up. It may not be a big deal, though the voltage loss due to the longer cable run does have some effect. I’ll live with the slightly longer cable run and see how the system behaves when finished, and if it turns out that the 24” of reduced cable run would greatly benefit me, I might re-do it.
So I chose to change the cable routing by running them to the front corner of the PH, and going over the canvas and into the interior.
I took the PH ceiling free of the PH fiberglass shell by removing the night shade and removing about 4 or 5 screws from the ceiling. I worked the canvas loose, and fed the cable to the inside.
One thing to do when working on the rough underside of my PH shell: Wear gloves! I got a few splinters of fiberglass in my fingers. They are like little needles. I’m still digging them out of my skin!
Then I used a Dremel to cut a notch for the cables in the PH roof liner.
I hate exposed wires, and wanted to hide them as much as I could, but I was limited to where I could run them under the various pieces of SMB trim because there is a severe lack of space and the bends would either be too sharp for the cable or the pieces under the trim would abrade the cables. I couldn’t figure out how to make a large enough channel under the trim so the wires would be safe, so I decided to let them run loosely over the interior rail. They are out of the way and generally follow the canvas when the PH is up, but when the PH is retracted, they kind of hang out and down a bit. I’m still thinking on a better solution….
From there, I ran the cable down and behind the valence above and behind the driver’s seat.
There was a gap at the top of the fridge cabinet that I could snake the cables through, although I had to use one of the best investments I have ever made: My $12 Klein fish tape. From there, it was the easiest part of the run to the solar controller because I was finally inside the cabinet with the planned controller location.
Time to mount the Blue Sky Solar Boost 3000i. I understand that SMB had installed the 2000e in a lot of vehicles over the years, and people seem to be really happy with them. The 3000i is newer model. Features that made me choose the 3000i were the 3-stage battery charging and that there are no DIP switches on the back. All the configuration is done from the front of the panel. That was a big plus for me, as I would have to either remove the microwave oven — a real pain — or remove the controller from the cabinet wall to change DIP switch settings if I had gone with the 2000e.
I had to relocate the furnace and A/C thermostats to make room for Blue Sky controller. I wanted the controller just above the TrippLite remote panel, because it made sense to me to have the battery-related panels near one another. Also, if I wanted the controller on that cabinet wall, it was pretty much my only choice for the location. The 3000i protrudes a couple inches behind the wall. Putting it elsewhere on the wall would have interfered with the space needed by the Norcold fridge or the microwave.
Here's the original locations of what SMBI had done.
I want to put the 3000i above the TrippLite panel.
3000i in place.
And the furnace and A/C thermostats relocated.
To cut the hole for the controller, I measured the dimensions of the back of the controller and drew a rectangle on a piece of paper. I cut out the paper rectangle, and then taped it to the cabinet wall where I wanted the controller to mount. I traced around the paper with a pencil, and I then drilled holes in the cabinet at the corners of my planned location.
I drilled the holes first to give my Makita multi-tool a place to bite into. You multi-tool pros may not need the holes, but I did, because I’m a weenie. Once I had the hole cut out, I repeatedly test-fitted the BSE panel in the hole, and the gradually trimmed the hole until the panel fit nicely. Not too snug to allow for heat expansion, but not too loose, either.
I love the Makita! It was really controllable and cut through the cabinet plywood like it was butter. It also left a really clean edge. A lot better than using a jigsaw, and being able to angle the blade all sorts of ways made working in a tight corner really easy. It made some nice and neat corners. I had bought it a couple years ago to do one project in a very confined space on the house, and had forgotten what a handy tool it can be. I could have used my Dremel to cut the hole, but it would have taken a lot longer. With the Makita, I had the hole trimmed perfectly in about 10 minutes.
Now that the controller was mounted, I connected the solar panel cables to the terminals with 10 gauge spade terminals. Piece of cake, as the terminals fit perfectly in the slots on the back of the Blue Sky unit. I also put a piece of red electrical tape on the cable near the end to identify the positive cable for anyone that might own the van later, or for me if I ever had to disconnect the controller in the future.
Blue Sky says the controller connections can take bare wire compression connections on cables as large as 8 gauge, but I opted for crimp-on connections instead.
Time to make 6 gauge cables for the run to the batteries. I bought a TEMCo hammer crimper on Amazon for about $14, as I could see no use of a high-end $150+ crimper in my future. It seemed to make really solid crimps, as they didn’t wiggle one bit after I made them.
Before I made the crimps, I put a liberal amount of flux on the cables and inside the lugs. I spun the lugs a couple times around the cable to smear the flux around. Then I crimped, followed by soldering of the lugs with a Bernzomatic torch. Not ever having crimped cables this size, and not being an expert at it, I think they came out well. After the soldered connections cooled for many minutes, I slid the heat shrink up to lugs and heated them. On the positive lug, I put another piece of red electrical tape on the heat shrink to identify it as positive. I bought a red cable for the positive, but since it will be in a corrugated sheath, the tape makes it easy to identify.
The Blue Sky 3000i has terminals for the battery cables with plastic walls between them. They are fairly narrow. I used a Dremel to trim the lugs slightly so that they would fit the terminal spaces.
Both ends of the negative cable. These have been crimped with the TEMCo and soldered, but before the heat shrink and corrugated sheathing went on. The lugs are copper with a tin plating. The left lug will connect to the house battery negative post. The lug on the right will connect to the 3000i. You can see the copper inside the lug after I Dremeled the side so it would fit on the 3000i's terminal.
On the positive cable to the batteries, I put in an in-line fuse holder. I couldn’t find a place locally that sold butt connectors for #6 cable, but I knew through online research that they existed, but were priced outrageously. I could have spent about $20 in buying a few connectors and shipping them, plus waiting for them to arrive.
Instead, I went to the local Big Orange Box store and got some soft 1/4” copper tubing for $10, the kind that you use to connect an ice maker to a water line. From this, I cut pieces to make my butt connectors with a tube cutter, and then de-burred the cuts a tiny amount with a drill bit. They fit the #6 cable perfectly!
Anyone want to buy 9'8" of leftover soft copper tubing from me?
One tip I saw in a YouTube video was to lay the cable out in your planned path to your connections and let it rest in a relaxed manner. Then make a mark on the cable indicating “up”. When you go to crimp your cable, align the “top” of your lug with the mark on the cable, then crimp it. This way the lug has reduced stress on the connection because you don’t have to fight the natural twist in the cable.
I followed this advice, and it worked out well. I never felt like I was fighting the cable’s natural twist.
After I made the cables, I put them in corrugated sheathing, and fished them through the cabinet wall, and made the connections. With everything in place, I put a fuse in the holder on the cable from the controller to the house batts. The 3000i booted up…so far, so good. Then I put a fuse in the cables going to the panels, and removed the cardboard from the panels.
Voila! Free energy from the sun!
The separator issue
SMBI had installed a SurePower 1315-200 battery separator, which, at the time (2008), was their standard procedure. The SP 1315 works well, but in my opinion, it is not the unit to use when a solar panel system is installed. I also think that SMBI should have installed a momentary switch on the Start Signal wire (I understand that they did start installing a switch in later years). As it was originally wired, every time the engine was started, both the engine and the house batteries were being tied together to run the engine starter. Disconnecting the Start Signal wire from the 1315 fixed this problem, while the engine’s alternator would still charge the house batteries when driving around.
As I said, I think the 1315 is a good unit, and mine works exactly how it was designed to work. The reason I think the 1315 is wrong in a solar setup is that when the panels are producing enough electricity, the 1315 will close, tying the engine and house batteries together.
This is both good and bad: It’s good because it allows the solar to charge the engine batteries. It’s bad because the engine starter can now draw from the house batteries as well as the engine batteries. At night, when the solar isn’t producing electricity, the 1315 opens and the starter can only draw from the engine batteries, and the house batteries don’t get hammered by the engine start. Which is how I want it to work all the time.
After the solar install, I stopped this behavior by disconnecting the Ground wire from the 1315, too. This forces the 1315 to open, separating the battery banks. The problem with the separator being open all the time is that the solar can no longer charge the engine batteries, and the alternator can’t charge the house batteries.
I’m going to leave it this way until I can install a different battery separator, and just re-connect the ground wire when camped for extended periods. I could do this indefinitely without getting a different separator, but I know that I will forget to disconnect the wire at some point in time. Still have my eye on the Blue Sea 7622, which has the ability to open the battery connection during start.
All finished and ready to go!
I drove a couple 10 mile runs on the local highway up to about 75 mph, and the panels seemed very secure. A few days later, I went on a quick overnight trip, about 350 miles. Panels were still secure, even after driving on rough dirt roads for about 80 of those miles. Gas mileage doesn’t seem to be affected, even though the whole setup probably added about 75 lbs to the van. Granted, I was without the wife and all her gear on the trip, so that could make up the difference in aero losses.
When I washed the van today, there were a ton of bugs squashed on the grill and windshield. Climbing up to wash the panels, there wasn’t a single dead bug on the lead edge of the front panel. I guess the air hitting the front of the PH is deflected upward with enough force to blow any bugs over the panels.
This is good news. I had wondered if I needed to create some kind of wind deflector to protect the panels and to keep air pressure from stressing the underside of them. If the bugs are being deflected by the PH roof, then the air pressure is probably not much of a worry, either.
At night on the trip, I ran the fridge, water pump, propane furnace, charged my phone with a 12V outlet, and LED lights. By 5 am, the batteries were down to 12.3V. With high thin clouds over most of the day, the controller had entered float charge by about 11 am.
I also ran the van’s radio using the “Radio Extra Battery” switch. I was impressed that the house batteries lost hardly any charge with the radio on. Kenwood listed the radio as using 10A, but I figured that was a peak rating that happened at boot and when using the DVD player.
Then I noticed that the van batteries had gone from 13.0V to 12.4V in the couple hours that the radio was on! I turned the radio switch off, and the van batts rose back up to 12.8V in a few minutes. I’m glad I didn’t fall asleep with the radio on, because I could have drained the starting batteries!
As for the weight of the panels and hardware, I estimate that I now have about an extra 60 lbs on the PH roof. I can definitely notice the extra weight when lifting the top (I have a manual PH). When the top is up and supported just by the PH springs, I can still push the top up higher by an inch or so. I think I am going to have to shorten the PH chains by a link or two. When I camped, I put support rods in the corners of the PH to make sure it didn't come crashing down unexpectedly.
First camping trip with the new solar setup at Ah Shi Sle Pah WSA, northwestern New Mexico. So happy!