Documenting my solar install

I'm going to post my solar install as it goes along; that way people can ask questions or offer advice As I proceed. Might save me some some hassle or mistakes along the way. When it's done, it can be compiled into a better thread for posterior's - I mean posterity's - sake.

This is inside the area I need to work with, inside the unit. The white box on the left is the battery monitor, already installed. The batteries are under the steps, and there's a panel not the right of the steps, under the fridge, through which I can access cables which run from the solar array, through the fridge's vent on the roof, down along the fridge, and come out into the area under the fridge. That area under the fridge is where that panel accesses. I can mount the solar controller just under the fridge. In the photo, the controller is just setting into place where I plan to mount it.

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This photo shows the steps removed, and batteries' positions.

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The next photo, from the outside, shows the outside panel which access the rear of the fridge. Directly above it, on the roof, the vent is visible. The vent permits propane exhaust and heat to be released.

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On the roof, this is a photo of the vent, with its cover removed. I snipped a hole in the screen and fed the cables, which will attach to the solar array, down alongside the fridge. Before feeding the cables down, though, both ends going down end in bare cable - indistuinguishable from each other - so I put masking tape around the end of the positive wire, so I could identify it down inside the unit. I want to make sure I attach that wire to the positive side of the controller, later on.

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Here's what I end up with, when I put the vent cover back on.

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Outside again, looking into the fridge's access panel, you can see the two cables coming down from the vent.

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The bigger picture:

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Note I had to drill a hole through the 'floor' which the fridge sets on, to run the cable into the access area beneath. I had already removed the thin piece of wood which covered the area on the inside so I could make sure the drill bit would not hit any existing gas or electrical lines.



Later on, I will cover that hole with a sealant - Dicor self leveling sealant - to keep water out, but for now I want to be able to move the cables, adjusting them as I work. When everything is attached in place, I'll apply the sealant.

Inside, there's a photo of the access panel removed. It was stapled in place from the inside, so I carefull pushed it inward. When I'm done, I'll Velcro it back in place so I can easily access the fuse between the panel's and the controller.

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Looking into the access area, you can see the two cables coming down for behind the fridge.

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And When I'm on the inside, I can tell which is the positive cable. Sorry about the fuzzy photo. I was tired, wet and cold from climbing on the roof...

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That's as far as I got today. I was kneelng in cold slush on the roof.

Tomorrow I'll mount the solar charger on the inside. I'm a bit concerned about the position of the cable behind the fridge, as we run it off propane most of the time, so in the morning I'll fire up the fridge and make sure the cable isn't near anything that gets too warm. Just a precaution. Should be fine.

I also found an interesting solution to the fusing, thanks to a local audio installer.

I was looking for a local source for low amp ANL fuses - need a 25 amp between the solar array (4 x 100 watt panels) and the controller, and a 30 between the Controller and the battery. The audio master suggested car fuses and a holder, but the holders only had 12 AWG wires attached, and I wanted 10AWG. His inexpensive solution?



Two female ends from a pair of 10 AWG spade connectors. Crimp them on the wire, and slide them on the fuse. Total cost for both fuses and connectors: $4.

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More tomorrow...

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Any thoughts, questions or suggestions so far?

A link to some videos by Renogy showing how to hook up a system. Doesn't matter whose panels you're using - nice for first timers


http://www.renogy-store.com/category-s/1853.htm

very nice, good pics, I like the step by step. if you have problems with that fuse set up you could go with a maxi fuse holder like this one.
http://www.cooperindustries.com/con...e_holders_andclips/hhx_maxi_fuse_holders.html
this one has #6 wire but I have seen them in 10. the fuses range from 20 amps to 80. most auto parts stores stock them. you should be ok with that you chose I added that just incase. highdesertranger

#6 wire would be fine - just didn't want to go thinner. Appreciate the thought.

Just remember the cables from the solar controller to the batteries are the most important ones. Larger is better, and no more than 4 feet in length, or relocate the controller. #6 would be minimal, #4 even better.

The controller will be about 10 or 12 inches from the battery, as shown in the photos. The battery cables with the kit are #10 and fit the controller connections. #4 or #6 may not - I haven't checked specifically. I'm not concerned with efficiencies and wire resistance with this setup, although generally bigger is better. Should I ever upgrade the system, I'll upgrade the controller, fuses, and the wiring size.

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For further info, the 400 watt system will read tidally provide about 20 amps into a 210 amp/hour battery array; and we only use about 25 amps in a 24 hour period. So pretty much overkill, unless we get into a week long storm.

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'Read tidally' above should be 'realistically'. Auto-correcting...

After going through the installation manual for the charge controller, I decided there wasn't much to do inside - except mount the charger - u til after the panel's were installed. The Dicor sealant used to waterproof the mounts needs 24 non-rain hours to fully set. Since we're expecting precipitation today and tomorrow, I'll wait until Tuesday to mount the panel's. It'll be colder, but dryer.

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In the meantime, there's an obstacle on the roof I'll need to remove so I can mount the panel's where I wish: it's a rotating bracket for exterior TV antenna.

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The bracket has a shaft which runs through the roof to a handle. The handle raises and rotates the antenna from the inside.

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Step one is to remove the handle by loosening the hex nut visible on the round base of the handle. It's spring loaded, and the handle and the large plate above it will pop off.

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The four screws visible in the above photo can be removed, and 1.75 inch hole in the roof is readily visible.



Since there are eight holes, I'd say the original installer made an error he had to correct: improperly aligning the base plate.

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The next step, on Tuesday also, will be to scrape off the the Dicor on the exterior bracket, and remove the bracket. I'll find a decorative plug to glue into the hole on the exterior, then fill the hole with expanding foam, just for insulation sake. On the outside, I'll screw an aluminum plate over the hole, then cover with Eternabond and/ or Dicor.

Eternabond is an adhesive, waterproof sheet that adheres over seams and seals them. Never used it, but it's got great reviews.

In addition to bracket, there's a plate on the roof where the antennas cable enters the camper, but that's not in the way. Just need to remove the coaxial cable.

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Correction above: the decorative plug will be on the INTERIOR, not the exterior lol.

In reference to 66788s wiring suggestion, here's a voltage loss table by volts, amps and wire size.. Indicates at what wire length system would sustain an acceptable 5% loss


http://www.solar-electric.com/wire-loss-tables.html

I was curious, when I read the specs on the charge controller, it stated it was only rated up to 360 watts, but was being sold with a 400 watt system. I figured I knew the answer, but called Renogy anyway. The response was the kit, at peak, would not send more than 340 watts to the charger, so it was within specs. Here's the kit:


http://www.renogy-store.com/400W-RV-Kit-ViewStar-p/kit-rv400d-vs.htm

They also have a 400 watt kit with an entry level PMW controller, 10' of 10AWG cable, and no battery cable for about $618-$660.

So 340 watts to the controller is a max 28.34 amps. If the amp charges at about 14.5 volts, that's about 23.44 amps to the battery.

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Going to the voltage loss chart, it would take between a 6.6 foot and 8 foot long #10 wire between the controller and battery to reduce the power by 5%. I've got about a 10" run, so the loss would be negligible. No reason to overdo the cables from battery to controller. Reading the reviews, people who reported the amperage they were measuring reported just over 20 amps, which is what I wanted. So the math seems to work.

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Also explains the fuses they recommended: 32 amp between panel's and controller, and 25 amp between controller and battery.

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Correction: if the controller charges at 14.5 volts. Not 'amp'. *sigh*

Which battery monitor are you using? I've read very good things about the Trimetric battery monitors.

AuricTech said:

Which battery monitor are you using? I've read very good things about the Trimetric battery monitors.

Click to expand...

The Trimetric 2025. I don't use all the advanced functions, but it stores usage by days, months, etc. I just use the basic functions to check daily usage, battery level, amp flow...

If you go to their website, the install and user manual is online.

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Today's chore: removing the old antenna bracket and sealing the hole.

Firs step was to take a screwdriver and remove the old Dicor from around the base. It pulled away easily from the base, but clung persistently to the rubber roof of the RV. Rather than damage the rubber roof, I'm just going to leave the old Dicor in place. It's ugly, but but better than risk tearing the rubber roof. It will be covered by the panel's, anyway.

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Once all the Dicor is peeled away, just unscrew the base from the roof and pull it up. Make sure the rubber roof isn't being pulled up, as well.



The shaft that protruded into the living area comes up as well.

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Not that the shaft is no longer sticking thought the ceiling, we need to seal the hole in the ceiling. It doesn't need to be sealed tightly, just covered with something that hides the hole and doesn't look too objectionable. Here's what we found:



It's even self adhesive.

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Installed:



DWs very happy to have that handle gone. She kept hitting it with her head getting in and out of the sleeping area.

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Up on the roof:

(Ought to be a song title lol)

Now the the bottom of the hole is closed off, we can add the expanding foam into the hole just for insulation purposes. Makes for a more professional job, in my opinion.

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The foam expands upwards, and needs to be scraped off. Actually, if you leave a little bit of the foam on the roof it might act as a bit of an adhesive/sealant under the metal cap.

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Next, lay your metal piece over top of the hole, and Mark on the roof where the holes will be, so you can drill pilot holes for the screws. (I found this round plate with predrilled holes in the plumbing section of Home Depot). Drill the pilot holes, put the plate back in place, and start your screws.

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Remember, you're only screwing into a piece of plywood 3/8 of an inch thick. You just want to snug the plate down. If you tighten too much you can strip the hole. So, tighten the screws.

There are several different things you can use to seal the metal cap. You can just put Daycor over top of the screwheads, and then all the way around the edge of the plate. That would be sufficient.

There are also different self-adhesive sheets of waterproofing material, such as Eternabond. I have never used to these before so I thought I would give one to try. I bought a 6" x 6" square sheet, for about $14 an RV store. It's just a matter of peeling off the protective film and pressing the sheet down over top of the metal. It is a flexible material so you can push it down over top of the screwheads, and it will conform to the shape of the cap.



It seemed to work pretty well, but I'm gonna go ahead and put Dicor overtop of the edges and over all the screw holes. Overkill, perhaps, but it doesn't hurt to be safe.

I also trimmed off the excess of the Dicor that was left sticking up after removing the bracket.

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That's as far as I got today. The opening is now filled and waterproof, and out and I'll Dicor it after the solar panels are installed, and I put Dicor on the panel mounts.

Tomorrow, hopefully, depending on weather.

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An addendum to drilling pilot holes : a good idea to know how your wiring runs, so to don't drill into wires. Manufacturers should be able to provide a wiring diagram.

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And if you do know of any 110v power lines n the roof - such as those from the AC unit - might want to unhook from shore power before drilling. Just saying...*grin*

This is a very good step-by-step and I'm sure it will help others!

WARNING!!!!

When measuring the real estate on your roof to fit the panels, don't forget the mounting brackets add width to the panel. A 21" wide panel will need 24" of real estate to mount. Do not ask me how I know this. I tend to bite when I'm ticked off at myself lol.

It's not going to be a major problem for me, but it might be for someone else in their install, so I thought it really needed to be mentioned.

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Here's what I mean:



I'm attaching the mounts as it's in the mid thirties outside this morning. I'll start the actual install about 1 pm, when its a bit warmer. Maybe 30 minutes per panel...

At least it's clear and sunny. Oh yeah - another

WARNING

Once in the sun, the panel's are generating electricity. Keep n mind, especially when handling attached wires with bare ends, as the instructions have you do when hooking up to the charge controller. It's possible to zap your system. I'm not sure if 12v 400 watts is enough to zap a person - any electricians out there? - but frankly I'm not keen on finding out ...

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First line above should read "I'm attaching the mounts inside the house..."

sassypickins said:

This is a very good step-by-step and I'm sure it will help others!

Click to expand...

Thanks. If it helps someone else, it's worth the additional time...

Taking a break while I consider the layout. It's not ideal; had I time before the winter hits for good, I'd order a few cables and separate the panel's into two groups, and I could avoid a few issues - like possible shading from the AC. But this will work. Below is a layout, and I'm considering a few adjustments - like pulling the panel in the lower right down and away from the ben, so it doesn't shade the corner of the panel. But I have to make sure all the cables from the panel's meet at a central point - a point they can all reach from their positions.



Since they are so close, and panels may overlap mounts (blocking the screws) - and so I don't run out of working room - I have to install them in a specific order. For each panel I have to clean the rubber around each mount, screw the mounts down,mother cover with Dicor.

Before moving them, I'll Mark their positions on the roof for reference.

Well, back at it.

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I'll also note that the two center panels are staggered, so I can access the mounts for installation and sealing.

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If I didn't mention it, the panel's are not screwed down yet. Just laid in place for consideration....

You could also mount the two center panels togather with aluminum angle 'iron' and bolt the angles to the roof. You could then reach fasteners under the panels. It wouldn't hurt to raise those panels up a bit anyway, as you have possible issues with shading. Any shading on panels seriously degrades their output. See the end of HandyBob's 'Battery Charging Puzzle' for a good discription of the problem.
https://handybobsolar.wordpress.com/

-- Spiff

Thanks Spiff. I'm familiar with shading degradation. I made adjustments, and it's just a matter now of not parking facing the wrong direction. A bit late, anyway, as the mounting is finished lol.

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IM also familiar with Handy Bobs site. Ts a great source of information, although he would probably harp on me for cable size and not having a mppt controller...

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OK, this next post is a long one...

Took a break, had a snack and looked over the layout. Decided on a few changes, and crawled back up on the roof. I wanted to make sure that the connectors for each panel met at a central location, and would reach to connect with each other, so I twist tied the cables together at the connectors, so I wouldn't mount a panel only to find out it wouldn't reach lol.

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Then I put Dicor around the patch I made yesterday. Dicor is self leveling, and evens out over the seam. You can't put too much on, so put it on heavily.

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Next, I cleaned the rubber around several mounts, so the Dicor would adhere better to the rubber.

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Next, I drills small pilot holes and put in the screws. These screws had plastic washers under the head, to help provide a water tight seal. Remeber what I said earlier, about just snugging down the screws. Slowly tighten them until you see the mount pull against the roof. Then stop.




I forgot to take a photo of the Dicor after it was added; but, just put a glob on top of each screw, then a very thick seam of it all around the edge of the mount, where it meets the roof.

Do this 32 times - 8 screws per panel, four panels.

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Next, we attach the cables from the panels. We're hooking them up in parallel, which means we're connecting all the positive cables together, and all of the negative cables together. The kit came with six connectors (3 for positive wires, 3 for negative), each which joins two cables together. First step was to connect the negative wires, then the positive wires, from the two panels closest to the fron of the unit. Then to connect the two panels towards the rear of the unit in the same manner.



The wires just snap into the connector. This leaves us with two positive and two negative connections, and we've used 4 of the 6 connectors.

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Using the last two connectors, we're going to the two positives together, then the two negatives together. The end product looks like this:

The last step on the roof would be to connect these connectors to the cable I preinstalled and ran down the vent. I'm going to,wait for a bit though.

According to the charge controller instructions, you first hook up the (powered) battery cables to the controller, then hook up the live cables from the panels to the charger. The instructions insist you cover the panel's before the hookup, so they're not generating electricity. Rather than do that, I'm just going to leave the panels disconnected, and connect the other end of the cables to,the controller. Then, when it comes time to connect the panels to the charger, I'll just get back onto the roof and make the final connections. Less chance of causing a short by accident.

So, it's back I imside the unit

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But it's also here I made a minor mistake. I had 40 feet of wire running from the roof, through the vent, and into the camper. Plenty of extra to make adjustments and pull more cable onto the roof, if needed. I had planned to tuck those big collection of connectors under one of the panel's - mostly for appearance, but also to offer a littl protection. I should have made sure I had plenty of extra cable on the roof at this time, but figured I do it later.

The woes of procrastination.

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I'm not going to mount the controller to the wall just yet - it'll be easier to make all the connections first in the limited space of the truck camper.

The charge controller has six places to connect wires under the unit - the first two for the panel wires, the second two for the battery cables, and the right two for an optional light. I won't use those last two. The instructions say to hook up the battery first, and have the controller on power when you make the the connection to the panel's. So we'll start with the battery.

There's going to be negative wire from the battery and a positive wire. The postive wire is going to have a 30 amp fuse, so I cut the two battery wires to length, then cut the positive cable in half, so I can install a fuse.

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On both sides of the cut I made in the positive wire, I'm going to strip a bit of insulation off.

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Then I'll slide the female half of a spade connector onto the cable. Generally, a male /female pair of spade connectors are used to connect two ends of wire. In this case though, I'm going to slip a fuse into the connectors, to protect the system. Here's one half of the positive battery cable with the connector attached.

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A pair of electrical crimped work the best. Can also strip the insulation from the wire.

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So what we end up with is one negative cable, with a metal ring on end, and a section of bare wire on the other end ( you may have to strip off a bit of insulation yourself.) the metal ring goes over the battery post, and the bare end goes into the controller. You also have two halves of the positive cable: one half has the metal ring for the positive battery post, and a spade connector on the other end. The other half of the positive cable has a spade connector on one end, and bare wire on the other, which connects to the controller.

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Here's a photo of the bottom of the controller: bare wire ends ends go into the holes on bottom, and the round green circles have screws, which you use to tighten a clamp which holds the wire in the controller.



I think I forgot to show this photo earlier, when I talked about the connections. Middle aged memory. To repeat, the left two holes - as you look at the controller - are for the panel's, and the middle two connect to the batteries.