If you want to live in your van full time or just camp in remote locations on the weekends, you will most likely need some sort of auxiliary battery setup to power your devices. Whether it be charging your cell phone or running your refrigerator for a couple days, auxiliary batteries can help you power your electronics without the risk of running down your starting battery and becoming stranded. Of course, learning to live without any electronics at all is probably the least expensive method, but that just isn't realistic for the majority of people out there.
The problem is that installing an auxiliary battery bank and/or solar panel in your vehicle can sound confusing and intimidating. But while it might seem this way at first, if you treat this as a learning opportunity and you are willing to put in the time, I promise you it isn't nearly as difficult and scary as you might think.
My goal for this post is to give you a step-by-step guide on how Jenny and I installed our auxiliary battery bank and solar panel into our 1985 Vanagon Westfalia. Obviously your power needs, and perhaps even your vehicle, will be different from ours, so it will be up to you to make certain decisions based on your own requirements and situation. However, I hope this post will serve as a helpful resource for anyone researching auxiliary power and solar power for their own installation, especially if that installation is inside a vehicle and most especially if that vehicle is a Vanagon Westfalia.
I do want to point out that I am not a professional, and I highly recommend doing additional research aside from this post. When researching myself, I found many insightful threads on The Samba and various RV and solar forums that did not relate directly to the Vanagon but that contained helpful advice and knowledge about solar systems in general. I will include links to some of these resources down below in the Conclusion section of this post.
Before you start planning your system, it is important to have a general idea of your power requirements. How many devices are you planning on running? How many amps do these devices use? How much storage space in your van/vehicle are you willing to give up? Will you be camped for multiple days at a time or will you be driving fairly often? The more you know about your setup requirements, the more you can cater your system to fit your specific needs, and the easier it will be when you go to purchase and install everything later on.
Before we began our install, we knew that the auxiliary batteries had to be large enough to power our TF-49 fridge, charge cell phones, camera batteries, laptops, etc via two DC dash plugs and one dual USB charging socket, and run a couple LED lights that we would install and hard wire to the fuse block. We wanted to be able to power these devices for at least three days without any charge going to the batteries. This would allow us to run our electronics for a few days without having to start the van and without having to rely on our solar panel just in case. We wanted to keep this system as simple as possible, meaning no rewiring of the radio, stock lights, etc. to the new battery, and we wanted it to be as efficient as possible to maximize our limited power. And finally, I wanted everything to be clean and organized since I am slightly OCD when it comes to organization, as Jenny could probably tell you.
Speaking of organization, I am going to divide this post into four separate categories to help simplify the information a bit:
- Battery Bank (this includes the batteries, isolator/combiner and associated wiring)
- Solar (this includes the solar panel, charge controller and associated wiring)
- Devices (this includes the fuse block, charging sockets and associated wiring)
- Conclusion (this includes an overall wiring diagram, some links to resources and some general information on power inverters and smart chargers, which we did not install but might incorporate into our system in the future)
Before we begin, I want to make it perfectly clear that in no way am I suggesting you should install your own setup exactly like ours. I will say it now and I will say it again: There are numerous compromises that must be made when installing an off-grid setup in your vehicle. Drilling holes to hide the wiring, not drilling holes but having visible wiring running throughout the cabin, installing these components in areas that allow easy access while not taking up too much space inside the vehicle - these are all things you will need to decide. There is no right or wrong way to do this. Do the research, plan it out and execute it so that you are happy with the outcome. We love the way our setup looks and functions, but some of you might not agree. And that is totally fine. At the end of the day, you need to design your setup to fit your own wants and needs. If you did that, then you did it right.
I have a feeling this is going to be a long post and is going to contain a lot of words and pictures, so you are more than welcome to skip to the sections that are most relevant to you. However, if you know nothing about this stuff, or if you are just curious to see how we installed our own system, I strongly encourage grabbing a cup of coffee, locating a comfortable chair and starting from the beginning.
OK, let’s begin!
Section 1: Battery Bank
The first thing you probably want to think about is your auxiliary battery bank. You can have a battery bank without a solar panel, but you can't really have a solar panel without a battery bank. Well, you could, but it wouldn't do you a whole lot of good.
As I mentioned previously, we needed enough battery capacity to run our fridge, lights and charge various devices via our 12V and USB charging sockets. We also wanted to have enough capacity to run these items for a few days without any sort of charge going to the batteries, just in case.
In order to fulfill these requirements, we decided to go with two true deep cycle 6V golf cart batteries wired in series to create a 12V power supply. The batteries we went with provide around 215 amp hours of power, which is probably overkill for most people. But we are going to be living in our van full time, and I liked the idea of having more power than we need.
If you decide to go this route, there are many good battery brands that can supply up to 230 amp hours of power, which is probably the most power you will ever need in a Volkswagen Vanagon. Trojan and Interstate batteries seem to be the most popular and probably for good reason. We initially planned on going with Trojans, but when I visited our local Sam's Club to see what they had to offer, I recognized the associate from high school. And as luck would have it, he was able to get us a great deal on two of their 6V golf cart batteries. Each battery regularly costs $103 ($85 plus an $18 core charge), but we got each battery for $50 out the door with a one year warranty, which wouldn't even buy me one of these batteries at regular price, much less a Trojan. So although Trojan and Interstate batteries are likely superior in every way, it was just too hard to pass up a savings of $200.
You might be confused about running your auxiliary power from two 6V golf cart batteries when just about everything requires a 12V power supply. Don't be. It is very simple to wire these two 6V batteries together to create a 12V battery bank. It is called wiring the batteries "in series," and this means that the amp hours remains the same (in our case 215) while the voltage doubles (6V to 12V). Just think of it as each 6V battery being one half of the 12V battery bank. When you put the two halves together, you get one 12V power supply.
To wire the batteries in series, all you have to do is connect the positive (+) post on one of the batteries to the negative (-) post on the other battery. You can place the batteries side by side, end to end or even have one 6V battery on one side of the van and the other 6V battery on the other side of the van. I do not recommend that last suggestion, but my point is all that matters is that you connect the positive (+) post of one of the batteries to the negative (-) post of the other battery. That's it! It doesn't matter which battery uses the positive or which uses the negative. As long as you have the positive post on one battery connected to the negative post on the other battery, you are good to go and now have a 12V system. In order to connect devices to this 12V battery bank, use the two terminals that are not being used to connect the batteries to each other in series. If any of this does not make sense, I included a link down in the Conclusion section that should help clear things up.
I want to point out there are several types of lead acid batteries you can buy. Some popular options include AGM, Gel and Flooded. These types of batteries fall under two categories: starting and deep cycle. Starting batteries are what you use to start your vehicle. They provide a lot of energy at one time in order to start your vehicle, but they are not meant to be discharged over long periods of time. Deep Cycle batteries are the opposite. While they do not supply a ton of energy at once, they are made to be discharged over long periods of time, which makes them the perfect candidate for auxiliary battery purposes. There are also marine deep cycle batteries, which are sort of a hybrid of the two but do not provide the same amount of power and lifespan of a true deep cycle battery.
We went with Flooded Lead Acid batteries, which means they require a little bit of water maintenance to ensure a maximum life span. However, if you keep up with the maintenance, they can last up to five years or more! Our batteries are also true deep cycle, which means they are made to be discharged to 50% capacity on a regular basis as long as they are charged back up afterward. You should never discharge any battery more than 50% as this can severely lower the lifespan of the battery. Whether you buy two 6V batteries or one 12V battery, buying a true deep cycle battery is something you definitely want. Because I am explaining our own system in this post, I am not going to list the pros and cons of every type of battery available to you. This is something you will need to research on your own. However, I will leave a helpful introduction to batteries link in the Conclusion section below.
Once you have decided which type and size of battery to buy, you will need to decide where to place this battery in your vehicle. When installing your battery/batteries into a Vanagon, there are many possible locations and many people who will give you their own argument for the best location. What you need to do is research and decide for yourself what the best location is for your needs. The location you choose will most likely depend on the physical size of battery you buy and how much storage space you are willing to give up.
Because we went with two 6V golf cart batteries wired in series, we decided to mount the batteries under the bench seat on the passenger side of the van. This helps to balance out the weight of the Westfalia cabinets, and, more importantly, it puts the batteries as close to the starter as possible.
Why is this important?
Well, when installing auxiliary batteries in your van, it is nice to have them connected so that they are being charged by the alternator while you are driving. Yes, we have a solar panel that is also charging the batteries. But on stormy and severely overcast days, it is nice to have an alternate charging source, especially during long drives. If you do not install a solar panel, then connecting the battery bank so that it can be charged by the alternator is almost a requirement. Between the alternator and solar panel, we have no problem keeping our battery bank topped up.
There are multiple ways to get your alternator to charge your auxiliary battery bank, and this usually depends on the location you choose to mount the battery. Some people connect the positive (+) post of the starting battery to the positive post on the auxiliary battery and wire an isolator/combiner in between. The main problem with this, especially if you are using a large battery bank like two 6V golf cart batteries, is that you are now relying on the alternator in the back of the van to run its current all the way to the starting battery at the front of the van, and then from there to wherever you placed your auxiliary battery bank. Keep in mind that DC current does not like to travel far distances, so a system like this is bound to see significant voltage drop. Also keep in mind that if you have a 30-year-old Vanagon, your stock wiring is also 30 years old and probably has some resistance to it. By the time the current goes from the alternator to the starting battery and then to your auxiliary battery bank, it will likely not be enough voltage to keep your battery sufficiently charged.
If you visit Jay Brown's website (I will leave a link in the Conclusion section below), you can get some great information on how to connect your auxiliary battery bank to your starter (not starting battery, but the actual starter of the van). I highly recommend visiting his site, but I will also try to sum it up below.
By placing your battery bank under the passenger side of the rear bench seat and connecting it directly to the starter of your van, the voltage only travels about three feet or less. So there is virtually no voltage drop. Your auxiliary battery will see just about as much voltage as your alternator is producing. This is good!
In order to achieve this, all you have to do is drill one 11/16" hole through the fire wall and you can run a wire from your starter to your auxiliary battery bank under the bench seat. Make sure to use a rubber grommet and wire loom to protect the wire. I know this sounds scary, but once you are done everything looks so clean! If you purchase your supplies from Jay like we did, he will include the correct size loom and grommet along with your wire.
In our setup, I began by building a box to house our two batteries. Many people simply place them under the seat and secure them with a strap or a board, but I'm paranoid, and, like I mentioned before, slightly OCD. So I went ahead and built a box. I wanted the batteries to sit flush against the front wall and left wall of the bench seat. However, you will notice if you look inside your bench seat that there are L-brackets and bolts holding the bench seat together, thus preventing you from being able to sit your batteries flush with these walls.
In order to get around this, I used a router to remove certain parts of the front, bottom and left sides of my box. This allowed me to slide my battery box over those bolts and have it sit flush in the corner. I then drilled two holes in the left side wall and used two bolts to secure the battery box to the side of the bench seat. To top everything off, I took a piece of clear Plexiglas, cut it to size and use it as a lid to help protect the battery terminals from spills and things accidentally bumping into them.
Building this box definitely took longer than I was anticipating, but in hind sight it was well worth it. It keeps everything clean and safe while still allowing the batteries to vent, and now I can store items under the bench seat next to the batteries without worrying about anything banging into them. It gives me peace of mind if nothing else.
Because our batteries did not come with handles, we used strap material and rivets to construct our own handles so we could lower these heavy batteries (70 pounds each!) into the battery box. We decided to just leave the handles in tact for future use.
OK, so now that we had our battery box built and mounted inside the bench seat and our two 6V batteries nestled securely inside the box, it was time to start wiring everything up. We began with the easiest part, which was running a 6AWG (gauge) wire from the positive post of one of the batteries to the negative post on the other battery. They were now wired in series, and I used a multi-meter to confirm that they were in fact giving us a 12V power supply.
Before I continue, I want to explain the importance of an isolator/combiner in your system and what it does. An isolator/combiner, also known as an automatic charging relay or ACR, is a device that automatically isolates your two batteries (starter battery and auxiliary battery) and automatically combines them. This is a very important component in an auxiliary battery system that is connected to the alternator. Basically, when you are turning your key and your vehicle is starting, your batteries will be isolated to protect any sensitive electronics that are attached to your auxiliary battery bank. A couple minutes after your vehicle is started, your batteries will automatically combine, which will allow your alternator to charge both your starting battery and your auxiliary battery. When you shut your vehicle off, your batteries will become isolated again so that any devices being powered will only draw power from your auxiliary battery bank, thus preserving the charge in your starting battery so you do not become stranded. Being able to use your electronics without running down the charge in your starting battery is the entire point of installing an auxiliary battery in the first place, so getting an isolator/combiner is essential to this system. If, however, you do not plan on connecting your auxiliary battery to the alternator and are instead relying on solar to charge your battery, then you will not need an isolator/combiner. In our system, we have our auxiliary battery bank connected to the alternator and to a solar panel.
There are many types of isolator/combiner relays out there, but we chose the Blue Sea Systems ACR 7610 because it allows for any size wire we want, which in our case is 6AWG. Some products like the Yandina come with wire already connected, so you are restricted to that size wire. For smaller auxiliary batteries, the Yandina is sufficient enough. For large auxiliary battery banks like our two 6V golf cart batteries, the Blue Sea Systems ACR is a much better choice.
Once our batteries were mounted in the battery box and wired in series to create a 12V power supply, we mounted the Blue Sea Systems ACR to our desired location, which is a piece of wood that is connected to the back of our battery box. After we mounted the ACR, we drilled an 11/16" hole through the firewall, which is necessary to connect the wire to the starter. We ran the wire into the loom and then through the hole and to the post on the starter. Once we connected the wire to the starter, we inserted the rubber grommet into the hole. The 6AWG wire was now connected to the starter and running inside the van to the auxiliary battery bank under the bench seat.
Because we had already mounted the ACR, we could see exactly where to cut the wire. We made the cut, stripped the insulation off the end of the wire, strung on the heat shrink, crimped on a non-insulated lug and then used a heat gun to activate the heat shrink. Then we connected this end of the wire to the ACR.
The next connection we had to make was wiring the other side of the ACR to the positive (+) post of the auxiliary battery bank. In order to protect the wiring, we installed a MIDI 80A inline fuse in this wire. We now had the positive post of the battery bank connected to the starter of the van.
To reiterate that last part, we ran 6AWG wire from the starter, through a hole we drilled in the firewall of the van and to one side of the Blue Sea Systems ACR 7610 (it doesn't matter which side). We then used 6AWG wire again to connect the other side of the ACR to an 80A inline fuse and then from the other side of the inline fuse to the positive (+) post of the auxiliary battery bank. NOTE: We did not yet install the 80A fuse - only the fuse holder. Do not install the fuse until the ground connections have been made.
We used the nearest seat belt bolt for the ground connection. We used 12AWG wire to ground the ACR to this location and then used 6AWG wire to ground the negative (-) post of the auxiliary battery bank to this location. All you have to do is remove the bolt, scrape away some of the paint (I am not sure if this is necessary, but I did it just to be safe), and use 1/2" lugs on your ground wires to connect them to the bolt, then reinsert the bolt and fasten. Once the grounds were connected, We inserted the 80A fuse into the inline fuse holder between the battery positive post and the ACR and were good to go.
I want to mention that the weekend before we installed the auxiliary battery bank, we installed a beefed up 6AWG alternator wiring harness that we also bought from Jay. If you have a newer vehicle like a Sprinter, this is probably not necessary. But if you have a Vanagon, this upgrade is a very good idea even if you are not installing an auxiliary battery. The stock Vanagon alternator wiring harness uses undersized wires and is 30+ years old. When I removed my old one, I found areas that were corroded and burned! Needless to say, at $35 it is a very good investment for your van whether you install an auxiliary battery or not.
We purchased our new alternator wiring hardness from Jay Brown. I do not make any sort of profit by mentioning Jay's name and I do not have any kind of investment in Jay's business. I just think his products and help are phenomenal and his prices are more than fair. His alternator harnesses also come with very helpful installation instructions, unlike certain other Vanagon parts dealers. But regardless of where you purchase, make sure you do this upgrade if you are installing an auxiliary battery bank into your Vanagon! It only took us 45 minutes to install and now our van idles smoother and starts up immediately.
Whew! that was a lot of typing and a lot of reading, but I think that sums up the auxiliary battery portion of our install. If you are still confused, study the auxiliary battery wiring diagram located at the very beginning of this section and read through it again. The next category is solar, which will probably take even longer than the battery section. So if you have to go to the bathroom, you might want to do so now.
Section 2: Solar
When dealing with solar panels, one of the hardest decisions you will have to make is where to place it/them on your van. As with the batteries, there are also several good threads on The Samba with tons of ideas on solar panel placement. For example, some people mount the solar panel directly to the roof while others mount it inside the front luggage rack. Some people run the wires through holes they drill in the roof while others run them underneath the pop top canvas railing. As you are probably beginning to understand, there are upsides and downsides to every single option. The best thing you can do is research these locations thoroughly and decide which option contains the most amount of upside and the least amount of downside for you personally.
Being that we have a large roof rack on our van, we decided that the best place to mount our panel is somewhere on the rack. We are planning on storing heavy items such as tools and gas cans in the front luggage rack, so mounting our solar panel there was not an option.
We also knew we wanted some sort of low-profile waterproof box mounted inside the roof rack to store extra blankets and winter clothes. So in an attempt to be as efficient with the roof rack space as possible, we opted to combine the two things and mount our solar panel permanently to the roof of the waterproof storage box. And in an effort to not drill anymore holes in our roof, we decided to run the solar panel wires through the passenger side air vent and into the van. I will explain this in further detail below.
My brother gave us a Renogy 100W solar panel starter kit a few months prior to this install, so we didn't really have to decide which size or brand of panel to buy. The more money we could save the better, so we just used what we already had and worked from there. If you don't already own a solar panel, you will certainly want to look into the different options available to you. They even make flexible panels that look really cool and are probably much lighter than ours, so it all just depends on your budget and requirements.
Our solar panel is 47” long by 21.3” wide, so before we could begin, we had to find a low-profile box with slightly larger dimensions than these. Several visits to local stores and hours of scouring the internet later, we came across the SKB 76-Note keyboard case. It didn't come completely waterproof, but it was low profile, was the perfect size for our solar panel and looked pretty durable. And since we found an open-box version at guitar center for $100 off, we decided to roll with it.
So, now we had our panel and roof box. The next step was modifying the box to be waterproof and then combining the two.
Because the box was intended to hold a keyboard, the inside contained a good amount of foam for padding. This wasn’t necessary for our purpose, so we began by yanking out all the foam. After that, Jenny spent about two hours scrubbing and scraping with multiple chemicals in order to get rid of all the glue/adhesive that was holding the foam to the box. Meanwhile, I painted the mounting brackets (which came with our solar panel starter kit) and the outside edge of the solar panel black so everything would blend in nicely.
When this was finished and the box was stripped and clean and the paint dry, we mounted the brackets to the solar panel, placed the solar panel with mounted brackets onto the roof of the box and marked where our holes would go. Then we drilled the holes in the roof of the box.
Although this box was already pretty durable, we wanted to add a little more structural support to the roof so that we weren't just mounting the panel straight to the plastic. If we had a flexible solar panel, this step would not have been necessary. We cut two large strips of aluminum to use as backing plates, and once they were cut and fitted to the inside of the lid, we lined them up with the holes we had previously drilled and drilled the same size holes in the aluminum plates. We then used a silicone adhesive to glue the aluminum plates to the underside of the box lid and mounted the solar panel to the lid.
In order to mount the box/panel assembly to the roof rack and prevent it from sliding around while driving, we used four U-bolts, one in each corner, and mounted them from underneath. We cut two more aluminum backing plates and mounted them to the inside of the bottom of the box just like we did with the lid. We then used silicone to seal up all the rivets from the inside of the box and then painted everything black.
The final step in waterproofing this box was to add a foam gasket around the bottom rim to prevent any rain/moisture from getting up into the box. We ordered 1/2" wide by 3/16" thick foam gasket tape from Amazon, but when we went to install it onto the box, we realized there is a big gap near the front handle that leads up and into the box. So, in order to remedy this we used a piece of aluminum L-channel and cut it so it would bridge this gap above the handle. We then used four rivets to secure this piece of aluminum to the box and used silicone once again to seal up the edges and the backsides of the rivets. Now we were ready to put down the gasket tape. However, we found out that the adhesive side of this tape does not stick well to the plastic, so we used the silicone adhesive again to stick the gasket tape to the box. Finally, the box was waterproof.
The last step before finally mounting the panel/box assembly inside the roof rack was to get all the wiring sorted out. Our solar panel starter kit came with two 20ft sections of 10AWG wire (one for the positive connection and one for the negative connection), so we started by connecting these wires to the junction box on the underside of the solar panel (if you buy from Renogy, they already have connectors assembled which makes this process very simple). We used a piece of masking tape to mark the very end of the positive (+) wire since both wires are black and we knew that once we mounted everything and ran the wiring inside the van to the charge controller, we wouldn't know which wire was negative and which was positive. This step is crucial and will save you a lot of frustration.
From the junction box, we ran the wiring into the box through two holes we drilled, through the inside of the handle and out two more holes on the front. We used clips and rivets to keep everything nice and tight and clean, and then used more silicone to seal up all the holes and backsides of rivets to keep water out. We also used a piece of wire loom for each wire on the parts that are exposed to the outside. This step probably isn't necessary, but we had the loom already and figured it is added protection. It is hard to fully explain how we ran the wiring, but hopefully the pictures below will give you a better understanding. One more thing to mention is, when mounting the wires inside the box as well as to the roof, be sure to keep the lid open and the pop top popped up so you can see how much slack to give the wire. If you forget to do this step, you might find that your wire is too short to open the lid of the box or the pop top of your van, and then you would have to redo everything which would be a major bummer!
That explains most of our solar panel/roof box setup, so before we get into how we ran the solar panel wires inside the van, let's first take a little break and discuss charge controllers.
Our Renogy solar panel kit came with a PWM (pulse width modulation) charge controller, but we decided to purchase a more efficient MPPT (multiple power point tracking) charge controller instead. This MPPT charge controller makes the most out of our 100W panel, automatically adjusting the input voltage based on how much energy the batteries require at that moment. A PWM controller will simply dissipate any excess energy as heat. However, PWM charge controllers are significantly less expensive than MPPT controllers. Many people use PWM charge controllers and claim they work just fine for their needs. Plus, if you start with a PWM controller, you can always upgrade to an MPPT later on if need be. Whichever kind you choose will just depend on your needs and budget. If you wish to learn more about PWM vs MPPT controllers, a quick Google search will bring up more than enough information and explain it in much greater detail than I ever could.
We went with the Tracer 2210RN 20A MPPT charge controller and the MT-5 digital display. You can find these as a package deal on Amazon and Ebay for around $150. So far everything has been working perfectly and I have no complaints.
Like everything else we've discussed, you will need to decide on the location for your charge controller. My initial plan was to place the charge controller under the bench seat near the batteries. I thought that keeping everything relatively close together would not only keep things organized but would also provide the least amount of voltage drop in our system. However, after some more research and emails with people who know much more than I do, I came to the conclusion that putting anything electrical that has a chance - no matter how unlikely that chance might be - to set off a spark near the flooded lead acid batteries is a bad idea. Also, according to the charge controller manual, it is recommended that the user mount the charge controller in a vertical position and allow six inches above and six inches below the charge controller for air flow. And mounting the charge controller under the bench seat wouldn't allow even close to enough space to satisfy this recommendation. So, we had to think of a new location.
If we hadn't already designed our solar panel to be mounted on the passenger side of the roof rack, we might have mounted the charge controller on the cabinet behind the driver seat. But as it stood, we only had 20ft of wire running from the solar panel, and we wanted to avoid the hassle of buying additional wires.
Another popular location to mount the charge controller is on the outside wall of the closet, but because we already installed the closet door mod (taking an old stock fridge door and installing it to the side of the closet to allow for a much larger access area) this was not an option either. We ultimately decided to mount the controller on the upper outside portion of the stock closet door. This location is in a good place relative to our solar panel and battery bank, it provides the recommended amount of space for air circulation, and because we installed the closet door mod, we never use this small stock closet door to access the closet anyway. We still made sure to wire everything so we can open and close this door if need be, but we rarely ever do. One last advantage of this location, at least for our setup, is it is much easier to replace a closet door than an entire Westy cabinet. So we didn't feel as bad about drilling holes in it as we would have felt about drilling holes in the side of the closet.
Installing all these components is a constant compromise between drilling holes and not drilling holes, but sometimes drilling holes is just necessary if you wish to have a clean install without visible wires running all over the place. So to connect the charge controller to the auxiliary battery bank, we had to drill a couple more holes: one from the closet into the water tank cabinet and then one more from the water tank cabinet to the table cabinet. We made sure to drill these holes as far in as possible so they aren't visible. Then we ran the charge controller wires (we used 10AWG for this too) from the charge controller on the outside of the closet door, through a hole we drilled in the closet directly behind the charge controller, down the backside of the closet door, into the water tank cabinet, into the table cabinet and then down to where the fuse block is located. From there we used the hole we had already drilled for the fuse block wires (see Devices section) and ran the charge controller wires into the bench seat and over to the battery bank. We then installed an inline 20A fuse on the charge controller positive wire as close to the battery as possible as per the charge controller installation instructions. We used solder and heat shrink to install this fuse holder. It sounds like a lot, but overall everything is very clean and tidy and the holes are not visible unless you are leaning into the cabinets looking for them.
Next came the MT-5 digital display for the charge controller. Although the charge controller is mounted to the stock closet door, we decided to mount the MT-5 display on the driver side of the bench seat kick panel. Ideally, it should be at eye level for easy viewing, but we didn't want to clutter up the outside of the closet door with too many gadgets (A.K.A. I like things clean and organized. I might have mentioned this before).
The charge controller/digital display kit came with a 6ft wire to plug the MT-5 display into the charge controller, which was just enough wire length to run from the charge controller on the closet door and down to the kick panel following the same exact path as the charge controller wires. We used zip ties and clips to keep all the wiring nice and neat, as shown in the previous images.
Now that we had the charge controller mounted and connected to the auxiliary battery and the MT-5 display connected to the charge controller, the only connection left to make was from the solar panel to the charge controller.
We ran the solar panel wires into the van through a couple water tight grommets directly behind the air vent. We had to drill the holes behind the air vent to achieve this. First we removed the paneling from the interior of the van on that side to get a good idea of where our wires should enter the van. This also helps prevent accidentally drilling through the panels. Once we drilled the holes, we used rubber grommets to protect the wiring and then inserted the wires into the van. The grommets are very tight and were difficult to insert and the solar wires were even more difficult to insert into the grommets, so I am 100% confident that no water will ever be getting into the van via these two holes. Not to mention they are up in the air vent where water doesn't even reach.
Once inside the van, we ran the wires up behind the interior panel and as close to the ceiling as possible and right passed the back of the AC unit. We used a couple clips to keep them tucked away and out of sight. Then we ran them around the corner and into a little space that leads directly above the closet. I'm not sure what Westfalia was thinking when they designed this closet, but there is a space directly above the closet that isn't accessible (except for small things like wires) and is really just wasted space. Anyways, this brought the wires directly above the closet, and then we drilled one final hole in the top corner of the closet and used our hands to pull the wires down and into the closet. This leads directly to the back of the charge controller, so we simply used a couple more clips to keep the wires organized and allowed enough slack to allow the closet door to be opened and closed if need be. We soldered on one more inline fuse holder with a 10A fuse on the very end of the positive wire and ran the wires through the hole we made in the closet door and connected them to the charge controller. Here are the pictures:
We now had our auxiliary batteries installed and connected to the alternator via the starter, we had our charge controller mounted and connected to the auxiliary batteries, and we had our solar panel mounted and connected to the charge controller. The only thing left to do was install our fuse block and accessories, which brings us to the third section of this post: Devices.
Section 3: Devices
I have a confession to make.
Although I am writing this post in the most logical order I can think, this was not the exact order we installed everything. In fact, we had our solar panel/roof box setup mounted on the roof rack with the wires running inside the van a whole week before we installed our auxiliary batteries and charge controller. And we had our fuse block and accessories installed one week prior to that! Nothing was wired up of course, but it was nice to have things mounted in their respective locations.
I guess my point is you do not have to follow this post in the exact order in which I lay things out. You don't even have to install everything at the same time. You could simply have an auxiliary battery and a fuse block for a while, and then maybe install a solar panel at a much later date if you decide that is something you want. The main reason we installed all these components slightly out of order is because we had certain parts figured out before others, so rather than wasting time until we had everything figured out, we just started with the parts we were certain we wanted. It's also nice to break things down into multiple weekends so you do not feel rushed or anxious and can take your time.
OK, devices. We began with our two 12V dash sockets and one dual USB socket. We knew these were things we wanted, and we knew the location we wanted to install them. Some people install their sockets on the bench seat kick panel, but we didn't like this location since it is annoying to access when the bed is down. So we installed them on the table cabinet right next to the table knob. This location provides easy access whether the bed is up or down. It also puts the sockets close to the fridge and the fuse block, which helps keeps all the wires as short as possible.
To install these sockets we used a forstner drill bit and drilled three holes equally apart (Yes, more holes!). Then we simply inserted each socket into the desired hole and started on mounting the fuse block.
We went with a Blue Sea Systems 5025 fuse block, which has six studs and a negative bus. Many people go for the 12 stud fuse block so they can connect more than six things, but since we only needed to connect five, this fuse block was sufficient for our needs. One thing to mention is you do not need to get a fuse block with a negative bus. You can simply ground each accessory separately to the chassis of the van, which is probably a better solution for those who want to connect a lot of accessories or who have their accessories spread throughout the van. However, since all our accessories (two Blue Sea Systems 12V dash sockets, one Blue Sea Systems dual USB charging socket, one TF-49 Truckfridge and one LED kitchen light) are in the same area of the van, it was more practical for us to use a fuse block with a negative bus.
We mounted the fuse block under the removable floor in the rear cabinet that holds the table. This keeps the fuse block tucked away and out of sight, and doesn't use up any extra room since this area isn't usable for storage anyway. It also puts the fuse block within a foot and a half distance from the fridge, USB socket and 12V dash sockets, which helps keep the wires nice and short.
First, we cut a little piece of wood and mounted it like a shelf inside the cabinet. Then we mounted the fuse block to that shelf and use 6AWG wire to connect the negative stud on the fuse block to the same seat belt bolt where we grounded the battery bank and ACR. In order to run the wire from the cabinet to under the bench seat, we had to drill a relatively small hole through the driver side wall of the bench seat and into the cabinet (this is also where we ran our charge controller wires to reach the battery). We used another 6AWG wire to connect the positive stud on the fuse block to the positive post on the auxiliary battery bank and installed a MIDI inline 80A fuse as close to the auxiliary battery as possible in this wire just as we did with the wire running from the battery to the ACR. Basically, you are going to want to install an inline fuse in any wire that connects to the positive post of the auxiliary battery. Make sure to keep the fuses as close to the battery as possible to protect as much of the wiring as possible.
Now that the fuse block was mounted and connected to the auxiliary battery bank, all we had to do was wire each accessory to the fuse block. We used 12AWG wire to connect the negative stud on each accessory to the negative bus of the fuse block, and then used 12AWG wire again to connect the positive stud on each accessory to the positive portion of the fuse block. For the LED light we used 16AWG wire (I will be creating another blog post later on to demonstrate how to make this simple and awesome full-length LED kitchen light for around $30). All we had to do from here was insert an appropriately sized fuse for each accessory and test to make sure each accessory worked. And they did!
Once everything was installed and working properly, I went back and used wire loom, clips and zip ties to tidy everything up. I also found a plastic case used to protect electrical outlets and painted it brown to match our Westy interior and then mounted it to the backside of the 12V and USB charging sockets. Once we are living in our van and have a bunch of crap piled into these cabinets, this will help to protect all the wiring connections on the backside of these sockets.
This pretty much sums up our entire install! However, I want to very briefly discuss power inverters and smart chargers, as well as various links to websites I described in this post, so I am going to write one more section to try and tie up all the loose ends.
Section 4: Conclusion
First off, congratulations for making it to the conclusion. I know that was a lot to read, so I am happy you are still with me.
At the bottom of this section I included a complete wiring diagram for our setup and some links to resources that I hope you will find helpful. I also want to very briefly discuss power inverters and smart chargers since these are items that are very common in solar system setups and things that we might possibly consider installing into our own system somewhere down the road. Because we do not currently have these in our setup, I will not go into super detail. However, if I didn't at least bring them up in this post, I would feel like it is incomplete.
Whether you have researched solar setups in great depth or you are currently researching it for the first time, chances are you have come across the term power inverter. Basically, a power inverter is a device used to convert direct current (DC) into alternating current (AC). This is a very useful tool in off-grid applications since most household items and appliances are designed to run off alternating current. But like everything else in this world, there are upsides and downsides to using inverters.
The upside is pretty obvious. Being able to use blenders, toaster ovens, laptop chargers and any other household item while off the grid is convenient to say the least. However, the downside is in the inefficiency of inverters. When an inverter is hardwired to your setup, it is drawing power even when nothing is plugged in. This can be remedied with a cutoff switch, but it is definitely something to be wary of. In addition, the process of converting DC to AC is inefficient and there will definitely be a loss of power in this process. The third downside, at least for us, is the price. There are two main types of inverters: modified sine wave and true or pure sine wave. Modified sine wave inverters produce a very choppy wave and are OK for very basic electronics like a radio. However, when using most household appliances and sensitive electronics like computers and cameras, you will need a pure sine wave inverter, which can be pretty costly depending on the size you choose.
With all that said, there are many people who incorporate inverters into their systems and do just fine. I am certainly not saying that using an inverter is bad or wrong in any way. These are just things to be aware of. Because we want our system to be as efficient as possible, we are opting to only use direct current. The dual USB charger we installed charges cell phones and iPads just fine, and there are many adapters we can use to charge camera batteries, laptops and other devices from our two 12v DC sockets. We might end up installing a small pure sine wave inverter somewhere down the road if need be, but for now we do not see a need.
Hardwired smart chargers are another popular option for your solar setup. They are easy to install and will automatically put your batteries through a four-stage charge cycle when you plug your van into shore power. If sized correctly for your batteries, they will charge your batteries quickly without overcharging them, and then automatically go into a trickle charge stage. This is a great idea for anybody who camps regularly at campsites with electrical hookups. They are also excellent for recharging your batteries when you return home from a long camping trip.
We came very close to installing an Iota smart charger into our own system. But between the alternator and solar panel, we do not currently see a need for the investment. We are not planning on staying at many campsites with hookups anyways, so we wouldn't be getting a lot of use from it. This could easily change somewhere down the road, but for now we do not plan on installing one.
Alright, that about sums everything up! I hope I have convinced you that installing an auxiliary battery and/or solar panel into your vehicle is not as difficult as it first sounds. The more you research, the more you map out your actual power requirements and the more you plan, the easier it will all be when you go to install. Remember that you do not have to install everything at once. It is perfectly fine to install a small battery now, and then maybe a solar panel later and maybe a bigger battery after all that. But I do think at least having a good overall idea of what you want to install and how/where you will be installing it will serve you best in the long run.
I have posted some resources below to assist you in your research. I also posted a complete wiring diagram to give you a better idea of how everything is connected to each other.
The feeling you get when you have installed your own system and can power your electronics for free using the sun is incredibly liberating. I definitely encourage you to try! If you have any questions, feel free to post them in the comments below and I will be happy to answer them. Good luck and thanks for reading!