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Solar Wiring Diagrams
for Campers, Camper Vans and RV's
SOLAR WIRING DIAGRAM SURVEY
The diagrams on this page are user-requested. Help me to help you and let me know what solar setup you are working on by filling out this survey: https://www.explorist.life/solarsurvey
Quick note before we get started. This is just one part of an overarching “How to Install a DIY Camper Van Electrical System” series. If you’ve just stumbled on this article directly without seeing that, there are likely some things we’ve already covered. If you want to check out that step by step guide, you can do that here: https://www.explorist.life/diy-campervan-solar
…or you can check out the individual lessons here:
Step 1: Learn the Basic Parts of a DIY Camper Solar Setup
Step 2: Learn How Many Batteries You'll Need to Power Your Camper (Power Audit Calculator)
Step 3: Choose the Type of Batteries You'll Use to Power Your Camper
Step 4: Learn how many solar panels you'll need to charge your Batteries
Step 5: Learn how to choose the correct charge controller for your solar panels (with calculator)
Step 6: How to size and choose the inverter for your camper
Step 7: How to add Shore Power to your Camper Electrical System
Step 8: Learn How to Charge your House batteries with your Engine Alternator
Step 9: Learn How to Choose the correct Battery Isolator for your System
Step 10: Learn how to Install and why you need a Battery Monitor
Step 11: Learn how to choose wire sizes and types
Step 12: How to Size Fuses in your System
Step 13: How to wire 12v Accessories in to your system
Step 14: Learn how to wire Lights & Switches (Including 2 way switches)
Please watch the video below as it will show you a few tips and tricks about how to use this page.
On the Images below, most of the components are clickable. Play around with it and click on any of the images you wan to know more information about. Below the Image, there is a toggle bar you can click and see a shopping list for the ENTIRE project.
Heads up! We are having issues with the diagram showing up below. If you can't see it, you should be able to access it here: https://www.explorist.life/?da_image=51400
[100w Solar Panels] Amazon Affiliate Link
[Roof Entry Gland] Amazon Affiliate Link
[MC4 Connectors] Amazon Affiliate Link
Battle Born / EXPLORIST.life Collaborative Solar Kit
[50 Amp Breaker] Amazon Affiliate Link
[Positive & Negative Bus Bar] Amazon Affiliate Link
[High Amp Battery Cut Off Switch] Amazon Affiliate Link
[250 Amp ANL Fuse & Holder] Amazon Affiliate Link
[100 Amp Breaker] Amazon Affiliate Link
[DC Fuse Block] Amazon Affiliate Link
[1/4 Inch x 10ga Lugs] Amazon Affiliate Link
[1/4 Inch x 8ga Lugs] Amazon Affiliate Link
[5/16 Inch x 8ga Lugs] Amazon Affiliate Link
[5/16 Inch x 2/0 Lugs] Amazon Affiliate Link
[5/16 Inch x 2ga Lugs] Amazon Affiliate Link
[3/8 Inch x 2/0 Lugs] Amazon Affiliate Link
[#8 x 14ga Lugs] Amazon Affiliate Link
Shore Power Plug
This is simply the wall plug in, in either 50 amp, 30 amp, or 15 amp that you can commonly find at a campground. This icon is also representative of if you were plugging in at somebodies house.
[30 Amp Shore Power Cord] Amazon Affiliate Link
[30 amp extension cord] Amazon Affiliate Link
[30 Amp Exterior Shore Power Input] Amazon Affiliate Link
[15 Amp 110v Breaker] Amazon Affiliate Link
[2 Space 110v Breaker Box] Amazon Affiliate Link
[110v Plug] Amazon Affiliate Link
[110v Outlet Box] Amazon Affiliate Link
[1/4 inch x 2ga Lugs] Amazon Affiliate Link
[Butt Splice Crimp Connector] Amazon Affiliate Link
[12ga Female Spade Terminal] Amazon Affiliate Link
[12v switches] Amazon Affiliate Link
Factory Alternator & Starting Battery
This is your factory alternator and starting battery.
[12v Puck Lights] Amazon Affiliate Link
[Maxxair Vent Fan] Amazon Affiliate Link
[12v Power Outlet] Amazon Affiliate Link
200 Amp Hour, 400 Watt Solar, Inverter, Shore Power & Alternator Parts List (Click to Expand)
Save
PrintMAIN COMPONENT DISCOUNT BUNDLE
OTHER MAIN COMPONENTS (available on amazon)
- Qty: 4 – 100 watt solar panel
WIRES
- Qty: 50ft – 12/2 Romex
- Qty: 15ft – 10/2 Romex
- Qty: 4ft – Red 2/0 Wire (5ft)
- Qty: 25ft – Red 2/0 Wire (25ft)
- Qty: 4ft – Black 2/0 Wire (5ft)
- Qty: 5ft – 2ga Wire Red (5ft)
- Qty: 5ft – 2ga Wire Black (5ft)
- Qty: 10ft – 8ga Red Wire (10ft)
- Qty: 10ft – 8ga Black Wire (10ft)
- Qty: 50ft – 10ga Red Wire (50ft)
- Qty: 50ft – 10ga Black Wire (50ft)
- Qty: 100ft – 12ga duplex wire (100ft)
- Qty: 1 – 30 Amp Shore Power Extension Cord
- Qty: 1 – 30 Amp Shore Power Cord
CLICK HERE TO ADD ALL WIRES TO YOUR AMAZON CART
LUGS & WIRE TERMINALS
- Qty: 8 – 3/8″ x 2/0 Lug (5pk)
- Qty: 26 – 5/16″ x 2/0 Lugs (15pk)
- Qty: 2 – 5/16″ x 2ga lugs (10pk)
- Qty: 2 – 5/16″ x 8ga lugs (10pk)
- Qty: 4 – 1/4″ x 2ga lug (10pk)
- Qty: 2 – 1/4″ x 8ga lug (10pk)
- Qty: 2 – 1/4″ x 10ga Lug (80pk)
- Qty: 8 – 12ga Female Spade Connector (100pk)
- Qty: 28 – #10 12ga Ring Terminal (80pk)
- Qty: 13 – 12ga Butt Splice Connector (100pk)
CLICK HERE TO ADD ALL LUGS & WIRE TERMINALS TO YOUR AMAZON CART
BREAKERS & FUSES
- Qty: 1 – 100 Amp Breaker
- Qty: 1 – 50 Amp Breaker
- Qty: 1 – 30 Amp Breaker
- Qty: 1 – 110v Breaker Box
- Qty: 1 – 15a 110v Breaker
- Qty: 4 – 250 amp ANL fuse
- Qty: 4 – ANL Fuse Holder
CLICK HERE TO ADD ALL BREAKERS & FUSES TO YOUR AMAZON CART
Misc
- Qty: 1 – DC Distribution Block
- Qty: 1 – Bus Bar
- Qty: 1 – Roof Entry Gland
- Qty: 3 – Battery Shut Off Switch
- Qty: 1 – MC4 Connectors (5pr)
- Qty: 4 – Solar Mounting Feet
- Qty: 2 – Electrical plugin Box
- Qty: 2 – 110v outlet
- Qty: 5 – 12v Switch
CLICK HERE TO ADD ALL MISC ITEMS TO YOUR AMAZON CART
Can you explain more about your ground wires? It appears they connect to the chassis of the van. I have a bus I am working on converting and I am unsure of what and how to ground things. I have a Victron solar controller and inverter similar to what you have in this diagram.
Should I be using the ground lugs on the outside of these?
Where do they connect?
Any advice would be great! Thanks!
The ground wires can be connected to either the chassis of the vehicle OR the bus bar. They are, pretty much, one in the same as even your busbar is connected to chassis ground.
Is the ground from the busbar there to complete the circuit for alternator power? I’m running a negative cable back to complete the circuit and was wondering if there is any other need to ground the negative busbar or any possible downsides to doing it should all my circuits be wired.
That is indeed what it’s mainly for. I can’t think of any downsides to not grounding the busbar… but if you run into any issues, it’d be pretty easy to add after the fact if needed.
Thanks Nate! You provide a great service.
Hey, Nate,
I really appreciate all the work you do and the wiring diagrams! Thank you!
So, I think I figured out that the “green Christmas Tree” thing is only needed if you use lithium batteries. Right?
In your picture above, you show two black wires with yellow ends, by the shore power. Are they two different things? What are they called? Do I need both?
Can I connect to the alternator if I am going to use the Yeti Generator instead of the DIY Solar System? If so, Since I would not use the “Green Christmas Tree” thing, Would I need something else instead, and what would that be?
Sorry, to all those of you who are very smart but I don’t have much knowledge of how anything electric works and I am just learning. So, please be patient with me. Thanks!
The green Battery Isolator is only for lithium batteries and if you are going to be charging directly off the alternator (which you won’t be doing with a Goal Zero Lithium Setup.
To charge from the alternator into a Goal Zero unit, you’ll be looking for a 300w plug-in inverter and an extension cord to your goal zero to charge the same way you would as if you were charging from the wall.
What did you use to create the diagram?
I used photoshop for the actual design and an image map software for the interactive features.
Nice looking diagram. What type of connectors are you using for your lights? Is it a step down connector?
Step down connectors are indeed ideal, but I typically just use butt-splice connectors. They are easier to find, less expensive, and more versatile. Step down connectors are the most-correct, textbook way to do it though. The diagram has been updated to reflect this.
Thanks for the amazing work on the research and for compiling article and excel sheet! It helped me out a lot and clarified a lot of questions I had. However just one thing I still dont quite understand. If yo would wire 4 12V 100w panels in series you would have 100W at 48V, to save space on the roof and get more power wouldn’t it be better to use 2 200W 24V panels? to get 200W at 48V?
Thanks a lot!
If the panels are feeding into a 12v battery bank, the voltage of the panels “doesn’t matter” if you are using an MPPT controller. 400w of panels at 24v, 400w of panels at 48v, and 400w of panels at 18v will all produce the same amount of power at 12v coming into the batteries.
…don’t think of the panels as ’12v panels’ because in all reality, 12v panels are really something like 17v-21v.
This is explained in a bit more in depth here: https://www.explorist.life/diy-campervan-solar/#charge-controller
Howdy ya’ll! Super great digram! Question though, how/where did you tap into the ignition wire for the BIM? I am not able to find ANYTHING that’s remotely helpful.
We used ya’lls diagram to a T and it’s been SO helpful.
Hey Lauren! I can’t remember exactly which wire it was, but you’ll need to splice into really any of the wires that are ‘hot’ when the key is clicked over. A good spot to start looking for this is behind the fuse box with your multimeter. Another good tactic for looking for a ‘switched’ or ‘accessory’ power wire is to find an aftermarket radio install manual and it will typically give you a wire color that will work for the ignition wire.
Where did you guys get the lithium ion battery?
Hey Tim! All of the items on the diagram are clickable so you can click them and find out where to buy them. Here is the direct link to the batteries though: https://battlebornbatteries.com/shop/12v-lifepo4-deep-cycle-battery/?afmc=explorist_bb67
Hello Nate,
First, thanks for all of the work you have put into the solar/electric schematic.
Second, I am in the middle of a Promaster conversion, rough wiring in, insulation in, walls/ceiling in, cabinet boxes in, plumbing rough in in, working on cabinet fronts and finish. When spring comes to Maine I will be doing the electric…solar, shore and engine charging. Three Li batteries, 12 and 120 volt systems.
I am looking to “steal” most of your system details.
I was looking through your parts list for solar/electrical and was surprised to see you call for romex type wire instead of a marine grade stranded wire. I have used stranded wire for the rough in and I am curious as to your thoughts on this. With your “do it right once” mantra I am thinking you would opt for stranded wire as it seems more in keeping with using the best quality materials.
Thoughts?
Hey Thomas!
No problem, glad you’ve found it helpful.
Regarding the solid Romex wiring, I really don’t have a strong opinion in either direction in terms of the 110v wire runs. I know most RV’s use Romex, which is why I leaned in that direction but I don’t have a really really good and compelling reason other than that.
I do know that the Yacht builders code forbids romex for vibration reasons, but that code is significantly more stringent than RV code, but I’ll look more into it and update the diagram as necessary.
FIrst off, awesome stuff!
I just purchased a 19 promaster 1500 136 hi roof, plan is to travel/ski/sell out of the van, weekend getaways
I’m trying to power: 12 v lights, maxx air 7500, dometic 60, charge computers, induction hot plate
plan is to go with: 1 lithium battle born, 30 amp controller, 175 watt solar panel, 2000 watt pure sine inverter, webasto 4kw heater
a few questions that will hopefully help others as well
1. for my system, are all of the breakers and shut offs the same…30am, 50amp 250amp, 300amp disconnects?
2. is what i’m proposing enough juice? i know i can always add another battery, but they are $950
3. is it necessary to tie into my van inverter?
thanks so much!
Hey Chris! Glad it helped! That sounds like an awesome project you’ve going coming up. Let me run-down your list of questions:
#1: You could absolutely go with the same wiring, breakers, and switches. It would be slightly overbuilt, specifically on the solar panel to busbar side of things, but that would allow for easy expansion down the road if you wanted.
#2: Really, that all depends on how much you plan on using everything. I’d recommend running through our power audit if you haven’t done so already. You can find that here: https://www.explorist.life/diy-campervan-solar/#how-to-perform-a-solar-power-audit
#3: I’m not sure I understand that question. Perhaps rephrase?
i meant alternator not inverter…late night research is tough
No worries, I thought that the case but didn’t want to assume. Tying into the alternator isn’t necessary, but is a good ‘just in case’ for cloudy days, or if your power demands simply are greater than your power storage/generation. It can always be added later if you are unsure.
Hi Nate,
First off, your schematic is very useful and I appreciate all the time you’ve put into it.
Couple of questions
Would you recommend adding a breaker between the 30 amp shore power and the inverter? Seems like ever other positive wire is on a breaker, why wouldn’t this one also be?
I bought the exact same inverter/charger as shown in this picture (I believe this is the same as yours) and I was wondering if I could wire up 2 types of shore power plugs. One of them a standard 15amp and the other would be 30amp like your diagram shows. Any thoughts on that?
Why do you use ANL Fuses for the 250 amp fuse instead of the resettable circuit breakers? Just cost? Seems like the CB’s are ~$30 vs ANL which is ~$12 (with fuse holder).
Do you think the breaker box for the 110 system is really necessary? I’m not very familiar with these systems but the 12 volt don’t have any sort of breaker box to surround the breakers.
I’ve got a basketful of amazon goods I’m about to buy 🙂
Thanks for all your help
Evan
Hey Evan! Glad it’s helping!
I’ll just run down your list of questions:
There will be a breaker protecting that line in the power pedestal or the wall you are plugging into (Think household breaker box).
Great idea… but let me suggest something easier. Run the 30 amp cord like I recommended then get a 30a to 15a adapter like this: https://amzn.to/2MnZF8c for when you need to plug into a standard 15 amp outlet
Mainly because I can’t find a reliable source with adequate reviews on a 250 amp resettable breaker that I really liked. :/
The box is necessary to hold the breaker. It’s the only way to mount the breaker in the system, unfortunately. I think it’s silly to have to use such a gigantic box for 1 or 2 fuses… but that’s one of those stupid problems…that’s a problem nontheless.
Hope that helps!
Nice set up but now I’m even more confused. Vehicle: 2018 Transit 250 w/150A alternator. I’m installing 3 200W panels I bought from Continuous Resources and they recommended a Victron Smart controller 150/35 installed in series with 10AWG from panels to controller with a 15A breaker and the 6AWG from controller to battery with a 40A breaker. The controller and breakers seems light compared to yours, yes/no?
I’m also wanting to be able to charge the house batteries with my alternator and trying to figure out the best system to use so as to protect house batteries and vehicle electronics. I’m planing on installing a 15A shore power input and a 2000W inverter charger. I’m still debating on batteries being about 400Ah AGM or 200-300Ah Lithium(cost is a killer). I’m a retired auto mechanic (12 years ago) so I understand the 12V system but incoperating solar and 120V has got me lot. Could really use some input.
Can you help me out?
Hey Jerry! Thanks!
Regarding your first question… I make these diagrams to be as comprehensive as possible. There’s likely 1,000 different solar setups out there, and most of them are correct. My goal with these, is to make them as comprehensive as possible so there is no question as to what works with what parts. I hope that makes sense.
It is worth noting though… that 600 watts of solar panels will put out 47 amps at 12.6v, so… not saying they are wrong… but you may check the manual for that particular charge controller as I think it’s only rated up to 500w.
Regarding the second question: If you follow this diagram exactly, you’ll have alternator charging, solar charging, and shore power charging as the inverter is both an inverter as well as a shore power charger.
Finally, for lithium vs AGM, I’ll point you in the direction of this blog post we wrote last year: https://www.explorist.life/choosing-a-solar-battery-bank-for-a-camper/
Hope that helps!
Hi Nate, Amazing info. Thank you for sharing and making DIY solar installers lives easier. Question, I see your solar panels are wired in parallel. What are your thoughts to wiring them in series and parallel? I am installing four 200 watt panels and the tech at the company recommended I wire them in series and parallel at the end. Also, and chance you’d do one of these specific to RV’s?
Thanks for all your hard work. I will definitely spread the good word to all my solar friends.
Thanks Allen! These solar panels in the diagram are wired in series and for 95% of applications, I recommend wiring solar panels in series. I could get into the ‘other 5%’ but it gets confusing pretty quickly… and 4×200 solar panels falls into that 95% that I’d wire in series.
A wiring diagram specific for an RV is indeed in the future!
Nate, awesome stuff. One question, is a battery monitor and shunt required?
Technically, no… but would you drive your car with no fuel gauge or speedometer? It’s the same principle. The battery monitor and shunt tells you how much battery storage you’ve got left as well as how much power you are actively gaining or losing.
wow you have done a great job with this wiring diagram post…great work and i thank you. my request would be for an rv (an older 35ft Diesel Pusher imported to Australia) I want to be totally off grid and be able to run one of the roof top aircons off the batteries. am thinking of 1400w of solar and 6 or 800 amphours of lithium with a 3 or 4000w inverter….but heres the rub; as its in Australia we run 240v and whilst the RV has been converted to have some 240v outlets in it, i still need to keep the 110 circuits/inverter for the fridge aircon microwave/convection oven and ofcourse it has a 110v LP Generator and i cant change them all over so the new system needs to run the 110 and a new 240v inverter. how would you approach this big build ???? your thoughts appreciated. my best lance
Nice! That’s going to be a hell of a project, but for sure doable. I would actually advocate for wiring the batteries into a 24v battery bank since you are trying to run an air conditioner. After that, You’re going to need TWO inverters. One for 110v power and the other for 240v power. The 110v inverter will need to be the big one as it’s powering the air conditioner. The 240v inverter can be smaller as it’s just powering plugs. You’ll need both of these to be inverter/chargers. The 110v inverter charger will provide ‘shore’ power from your 110v generator. The 240v inverter/charger will be your actual shore power connection. From there, you’ll just need a 24v to 12v step down converter for all of the on-board 12v appliances.
I’m also planning to run an air conditioner with 400ah lithium and 600watts of solar. If I did wire the batteries for 24v I suppose I need a stepdown for my 12v fuse block? How would using a 24v battery bank change the diagram regarding the alternator charging? Are there any other special considerations I would have to make when following your diagram if I did go for a 24v battery bank?
Hey Patrick! Nice! You’d need a step down for sure before your distribution block.
You’d also need a b2b charger or a buck-boost between the alternator and the house batteries.
Hey Nate, you may want to consider replacing the twist-on connector for shore power with a Smartplug. They claim 20 times the electrical contact vs twist-on, so it should handle a fair bit of amps. Great chart otherwise, you’re creating great stuff here.
Thanks for the suggestion, but I will leave the current recommendation as the smart plug is nearly 5 times expensive with no added benefit. 20 times the electrical contact means nothing to me, personally, as an inlet rated at 30 amps is still 30 amps regardless of how much ‘contact’ it has. Feel free to use whatever you like in your own setup though.
Hey Nate,
Awesome diagram!
I would like to do 15 amp shore power hookup instead of 30 amp. Would i need a different cable besides 10/2 could i use the 12/2? also should there be a breaker before the shore power hits the inverter or is it not needed?
Thanks! Ultimately, you can do whatever you like, but I don’t think that’s the place to save a few dollars. Even if you are never going to plug into 30a, using 10/2 will allow you to use a longer shore power cord if needed. You don’t need a breaker on that line as the breaker is in the campground power pedestal or in the breaker box in the wall.
Been Following your content for a while now. Been learning a lot, thank you! I am going to set up a 350 Watt set up on my boat. Question- I will be using a generator to charge the batteries on cloudy days so is it wise to add a fuse in the shore power in line in case of voltage surges?. thank you in advance.
Your generator SHOULD have a breaker installed that protects the 110v out.
Hey Nate,
Total 12v electrical novice here.
I really like your system and how clearly you laid it all out.
My question is about powering something like an Raspberry Pi and some led strings, how do you set the amperage that your delivering to these devices so as to not over power them?
Cheers,
Elle
I believe a raspberry pi runs at 5v (via USB?). If that’s the case, I’d just install a 12v USB outlet near it and just go from there. For led lights, as long as they are 12v led lights, they can be wired in without any kind of extra step down converters.
A component will only draw as much power as it needs to operate. As long as the voltages match, you’ll be good to go.
Hi Nate, I keep seeing people (on Facebook) who want to switch & Dim lights from 2 location Most people reply that there is no such thing as a 3 way dimmer for 12V, But one could do 3 way switch on to a dimmer which is not as good but you can turn it off from your bed, This is the way I do it using SPDT ON/ON switches. Basically you connect the power to the center pole of the first switch then run 2 wires from the 2 outside poles to the 2 outside poles of the second switch and from the center pole of the second switch to the dimmer input and the out put of the dimmer to the light, also run a common to the dimmer & Light
Yeah, I’ve seen that requested a bit too. I’ll be sure to add how to do that when I make a ‘how to wire switches’ post.
Great Work!!!
I love the interactive image and your videos are top notch.
My question is about the load bus bar. You have a 50 amp load from the charger controller, a 250 amp load coming from the batteries and 250 amp coming from the inverter/charger. Is there any chance of back feeding the charge control circuit?
Nope. 🙂
The buss bars are 3/8, the 5/16 lugs don’t fit.
Enjoy your site but have a question. On my home built teardrop I am using a WFCO converter / charger. When I plug into shore power it will charge the battery. All lights and fan are 12v only. I would like to add a 100 watt solar charger or larger to this system, for use when boon docking. Do you have suggestions on how I could install solar but still keep my WFCO converter in place?
For that, you’d simply be installing the panel(s), charge controller, wires and fuses and hooking directly to the battery/busbar.
Hi Nate,
Thanks for the amazing diagram. I’m wondering if you have or will be doing a diagram for a travel trailer specifically? Our trailer is only 30amp and we want all outlets, etc powered. How do I connect to an already existing 12v and 110 breaker box. Do I just run the shore power through the inverter (3000w multiplus) and then to the existing 30amp breaker? Do I need a separate breaker box like you have in the diagram? Do I need an automatic transfer switch or does the inverter do that on it’s own?
Thanks!!!
I will be doing a wiring diagram for an existing system eventually, but as it stands right now, it’s not in the immediate plans, BUT… if you haven’t seen it already, we have a video where we installed a new solar system into a truck campers existing system. You can watch that video here: https://www.youtube.com/watch?v=Ht1kl37pJ2E
You won’t need a transfer switch as the inverter has an integrated transfer switch. That video should answer the rest of your questions though.
This looks like a total conversion (not that I am opposed to that!). I would have to integrate this into an existing system that is already in my trailer?
In addition to your absolutely beautiful diagram, do you have a normal electrical schematic? (being an electrical person myself!)
Sweet jobs and NICE documentation!
Thanks!!
This wiring diagram, in particular, is aimed at a from-scratch build, but can be pretty easily adapted into an existing system.
I don’t have a ‘normal’ electrical schematic, sorry! Hope the one that’s posted helps nonetheless.
Hi Nate, thanks for all the hard work you’ve put into this. I’ve found it extremely helpful. I’m doing a very similar system but with 2 155 amp hour AGM batteries. So far I’ve followed everything you laid out. I’m looking at installing the Battery Isolator and since I’m not using Lithium Ion Batteries I’ll be going with either the Battery Doctor or the Keyline Charger. So far people seem to be using 2 inline 100 amp fuses and I was wondering if that seemed right to you or if sticking with 2 250 amp fuses were still the right move. Also if I still needed to use 2/0 wire as some kits are coming with significantly smaller wire. Thanks again for taking the time to respond to so many peoples questions. You’ll Rock!
Hey Peter! So, I actually just released a few blog posts that will help clear some of your questions up. The first two deal with isolators and charging via the alternator:
https://www.explorist.life/how-to-charge-diy-camper-van-batteries-with-vehicle-alternator/
https://www.explorist.life/how-to-install-a-battery-isolator-in-a-camper-van/
And the next two talk about sizing fuses and wires:
https://www.explorist.life/what-size-fuses-to-use-for-a-diy-camper-electrical-setup/
https://www.explorist.life/what-wire-to-use-for-diy-camper-solar-system/
I’d still recommend the 2/0, but the ‘why’ is covered in the above blog posts.
Hey Nate,
Sat through about 5 of your vids last night. Really good stuff. I’m a total van solar novice. I’m retro-fitting a Mercedes 2500 passenger van. My biggest question is: By using an isolator (and wiring like you’ve shown us here), can I utilize all the current wiring/electronics in the van when I’m using solar power w/o draining my vehicle battery? Hope that makes sense. Basically, I want to be able to leverage the current van set up, add to it will other stuff, and not drain my vehicle battery if I’m not driving or plugged in. Thanks.
The isolator simply seperates the starting battery from the house battery. If you are using items that are connected to the starting battery, the isolator will not help solve any problems. The isolator will keep the starting battery from draining as you are using items connected to the house battery.
Hi Nate,
I love that you posted this diagram! You posted exactly as I was starting to plan a solar set up for my bus and we are starting with this, almost exact, set up. I have one addition that is troubling me. I am adding a tankless hot water heater that requires a two pole breaker and 6 awg wire. I am just not sure how to run the wires through the circuit breaker when there are two poles….any ideas?
Thank you
I feel like that’s going to be a massive 220v hot water heater and will be mostly incompatible with anything on this diagram. Which water heater are you trying to install so I can advise a little better?
Basically copying your diagram. Been a fan for quite a while.
Do you recommend the LiFePO4 Battery Isolation Manager over the Sterling Power Alternator Protection Device for 12V Alternator? Or am I confused on their purpose? Both from Battleborn.
Hey Klutch! We just released a blog post talking about that exact topic. You can check it out here and it should answer your question: https://www.explorist.life/how-to-charge-diy-camper-van-batteries-with-vehicle-alternator/
Thank you so much for the clean easy to digest and follow info on this subject. I am doing a conversion on a promaster and the electrical system was my biggest unknown. Your diagram is almost an exact fit for the system I want to build. I wanted to max out the solar on my roof so I have already purchased 8 x 100w reneogy compact solar panels and plan to purchase 4 of the battleborn batteries. The difference in my system would be 800w – 400aH. I plan to just buy everything on your list and follow the diagram but I have a couple questions:
1. I calculated that I would need to buy the Victron 150/60 charge controller instead of the one listed, is there any other wire gauges, fuses…that I would need to size up due to the 800w – 400aH? or any other changes to the diagram?
2. When I looked at your 400aH bundle on Battle Born it also has the Victron Digital MultiControl. I don’t see this on the diagram above. Do you recommend this? If so where does it go and what is its function?
Thank you
No problem! 😀
I’d recommend double-checking your math on the charge controller as I think both the amperage and voltage will be too high for the 150/60. My calculations are telling me you’ll be looking at the Victron 250/85
Matching a solar controller to your panels is pretty confusing no doubt. If it helps, I just released a calculator to go along with a newly revamped instructional blog post about sizing your charge controller to your solar panels. You can find that here:
https://www.explorist.life/how-to-choose-a-solar-charge-controller-for-your-camper/
In regards to wire and fuses, yes… you will need to change wires and fuses from the charge controller to the busbar. I’ll get to another wiring diagram at some point, but in the meantime, here are two new resources that will teach you how to size wires and fuses.
https://www.explorist.life/what-size-fuses-to-use-for-a-diy-camper-electrical-setup/
https://www.explorist.life/what-wire-to-use-for-diy-camper-solar-system/
Regarding the Victron Digital MultiControl: That allows you to control the inverter remotely. You can turn it off, on, charge only, or just generally check the status of your inverter. Yes, it’s nice to have, especially if your inverter is mounted in a space that’s hard to get to. The wiring on that is simple a data cable, but you can see the instructions here: https://www.victronenergy.com/upload/documents/Manual-Digital-Multi-Control-GX-Panel-EN-NL-FR-DE-ES.pdf
Nate, with regard to the Digital MultiControl, how does it differ from the Color Control GX? The Battle Born site has a variety of controllers and being new to this i find it confusing. There is also a Magnum remote control, battery monitor and solar remote display. How would i know it i need these and what are they used for? Perhaps there is a review of these devices that would help. I apologize for extreme ignorance but i am trying to learn. Love the site and all the helpful information. You and Stephanie make a great team.
The Digital MultiControl is purely for the controlling the inverter. The Color Control GX is more of an overall system overview kind of device that you can plug your inverter, charge controller, BMV, and more into that will give you even more monitoring features if that’s your kind of thing.
Will definitely be doing more reviews and comparisons in the coming months.
Nate, you mentioned in an earlier blog that you were going to do a video on recharging house batteries from the vehicle’s alternator. Have you done this yet as I have not been able to find it. Also, my SUV has a 6 pin recepticle for trailers and my trailer that I am converting to a teardrop currently has a 4 pin plug. Is it as simple as converting my plug to a 6 pin plug with the extra pins providing power to connect to an isolator in front of my house battery? And, how does the isolator’s ignition post work with this setup? Probably too many questions to answer in one response… Thanks, love your site and great blogs.
I haven’t made the video just yet but I JUST released two blog posts that talk about charging with the alternator:
https://www.explorist.life/how-to-charge-diy-camper-van-batteries-with-vehicle-alternator/
https://www.explorist.life/how-to-install-a-battery-isolator-in-a-camper-van/
I don’t mess with 6 pin connectors as they only charge at a few amps and are generally not adequate for ACTUAL charging with the alternator.
The Isolator ignition wire is connected to a wire that is ‘hot’ when your ignition is on. The isolator would be mounted in your pulling vehicle with a heavy gauge wire ran back to the trailer. Consider making the removable connection from the vehicle to the camper with adequately sized Anderson connectors.
Thanks for putting together this useful diagram. Do you have a layout of this setup without the solar and alternator pieces. I am installing a 12v system in my cargo work trailer. I will be charging the batteries with shore power (generator or 120v receptacle). I would like to take this to a job site and use the trailer without the generator running. I will eventually add a solar setup to this trailer.
I don’t have a diagram for that in particular, but you see where the alternator feed and the solar feed connect into the busbar? Just don’t do any of that. The rest will stay completely the same. You’ll have to go back and re-count wire lug sizes, but this diagram will give you a fantastic starting point for you to make your own changes as necessary.
Hello Nate,
Thanks a lot for this diagram it helps me a lot with putting up my own circuit for a future camper van.
I just do not understand what makes you choose to put 30a breakers, 50a breakers etc.?
Which factors do you base that on?
Best regards, Bjorn.
Of course! It’s a bit confusing for sure. We just dropped a new blog post that should answer all of those questions for you. Check it out here: https://www.explorist.life/what-size-fuses-to-use-for-a-diy-camper-electrical-setup/
Hello Nate,
I am converting a 2019 Ram Promaster 3500, extended 159″ highroof. 220 amp alternator, 300 amp/hr Li from Victron, 12/3000/120 inverter/charger, 100/30 mppt, 1240 watt solar, Battery Monitor, Colour Control GX to name the main parts. What I wish to ask is regarding ones ability to charge from the Alternator at the highest and most efficient rate possible without causing damage to the alternator itself. There was a mention about a battery to battery charger in one of your replies, and I wish to ask if you could expand and possibly provide a part or model from Victron or someone else which would do the trick.?
Thanks for the great work you have done. I will use your links for all items I am buying online.
Hey Stephen, Awesome! Sounds like a cool project! Sorry for the delay, but I was actually in the middle of writing some more blog posts that would answer your question more thoroughly than I could in a reply. Take a look over these two blog posts and see if they clear up what you’re looking for and if you have any more questions, feel free to reach back out as always.
https://www.explorist.life/how-to-charge-diy-camper-van-batteries-with-vehicle-alternator/
https://www.explorist.life/how-to-install-a-battery-isolator-in-a-camper-van/
Nate,
What is the purpose of the on/off switch wired to the LI-BIM?
From my understanding the purpose is to bypass the BIM and directly connect the coach and chassis batteries in order to jumpstart the van in an emergency situation, is that correct?
Thanks for all your work on this site, it’s amazing!
Evan
Yes! That’s exactly what it’s for. It’s totally optional but is nice to have. We actually used it the other day when the temps were in the negatives and our starting battery needed a little ‘help’ with some thick diesel.
Awesome, thanks!
On your diagram you show the battery monitor connected to something. When I click on the link, I don’t see anything on the next page that looks like what you’ve connected the battery monitor to in the first page.
Can you tell me what the battery monitor is connected to in the diagram?
Of course! That’s called a shunt. You can learn about that here: https://www.explorist.life/how-to-install-a-diy-camper-van-solar-battery-monitor/
i have learn so much from you today,,i plan to build 400 watt 2 lit bats at 100 amps,,and i will buy them thur your site and use your diagram to help me install,,thank you,,i think you should CHARGE everyone who uses your plans $5,,you be rich,,,you could buy you a nice used car,,haha,,thanks,,James
Haha! Thanks. Glad you’re finding all of this helpful. 🙂 🙂
I do not want to mount the solar panels on the roof. Do you know of a sidewall plug that is made for 10awg that I can use instead of the roof gland?
By the way, great work on this diagram!
Yes! I would recommend something called the “Anderson Powerpole” line of components.
Cool! I will look into that.
I had one more question. What is the purpose of the 250a fuses? That seems like a big fuse. I am planning a 200 Amp hours battery bank.
Great!
The 250 amp fuses protect the wire that the fuses are attached to. For info about how to determine what size of fuse you need, check this out: https://www.explorist.life/what-size-fuses-to-use-for-a-diy-camper-electrical-setup/
IMHO I would add in something like this to your diagram https://www.amazon.com/Charger-CHGeek-Waterproof-Voltmeter-Motorcycle/dp/B07F84VVB4/ref=sr_1_2?keywords=Quick+Charge+3.0+USB+Charger+Socket&qid=1551719299&s=gateway&sr=8-2 in place of the 12VDC socket.
Feel free to add whatever 12v devices you like into your system. Wiring that device would be the exact same as wiring the 12v socket.
Hey Nate!
As always, incredibly helpful!
Just as a product consideration for making lighting connections and other 18 to 12 awg wires… the Wago connector. (https://www.amazon.com/Connector-Assortment-Compact-Connectors-PCT-212/dp/B076ZNGR46/ref=sr_1_4_sspa?keywords=wago%2Bconnectors&qid=1551910630&s=gateway&sr=8-4-spons&th=1) (I do not have any affiliation to this product.) An electrical engineer I’ve done work for in the past got me to use them for lighting control installs and they have been fantastic to work with. They are finger safe when live, forgiving if you need to assemble and disassemble multiple times, well made and relatively cheap.
Hey, great! Those look like a VERY easy solution. Thanks for the lead!
Hey nate, great stuff. Arent you missing a Victron BMS to protect the battery?
Thanks! Nope, those Battle Born Batteries have an integrated BMS already built in.
ok so the battery it self also protects it from low voltage and high voltage? Because i see many victron batteries with victron battery protectors after the solar charge controler for example or on the dc load side of the battery.
Correct. Not all Victron Batteries have an internal BMS, which is why there is an external BMS.
Hello, very much appreciate your detailed diagram! My question is, Is it optimal to use a shore power breaker and auto transfer relay? I know the Victron Multiplus inverters auto transfer to shore power when the juice is supplied but would another breaker between shore and charger be redundant or just being extra safe?
An extra breaker between the shore power plug and the charger is just redundant. I talked a bit more about that here: https://www.explorist.life/how-to-add-shore-power-to-a-diy-camper/
Thanks so much for the great info, you’re site is super helpful. I’m installing my electrical on a ford transit and was wondering if you have any details on actually connecting the system to the car battery. I’ve seen alot of great install info, but not much on actually connecting it to the battery. Looking at using a terminal fuse on the (+) car batt terminal >B2B charger>busbar>house batt. And connecting the (-) terminal of the car batt to a chassis ground. Sorry if you’ve answered this before, and thank you!
Could I get some clarification on your question? All of the information to connect everything is in the diagram above. Shy of saying: Step 1 – Loosen bolt on battery, Step 2 – remove battery terminal from battery post, etc… I’m not sure I’m following. Let me know the part you are actually struggling with and I’ll see if I can help you out.
Hey Nate – This is by far the best resource I’ve come across. Big thanks! I’m building out a 200 watt, one 100 lithium amp hr battery, with 2000 watt inverter. Will the rest of the components you have outlined be an issue with a smaller system like that? I plan to expand in the future but just trying to think of any drawbacks for the time being.
Hey Mike! Yes and no… The charge controller will be a bit oversized, but ultimately that’s no problem if you are planning on expanding eventually, although adding panels retrospectively is kind of a pain in the butt. I’d REALLY recommend adding the full wattage from the start. If you can’t; under-sizing your panels at this time will do the system no harm as it stands.
You can hold off on more battery capacity if you need to, but know that the batteries can’t be discharged faster than 100 amps continuous or 200amps for a surge, so anything you’re planning on running that’s more than 1200 (coffee maker, instant pot, etc) watts is going to be a no-go until you get that 2nd battery.
Amazing site you guys put together here and hours invested!!! What a wealth of information!
A couple more questions revolving around chassis ground. I read the comments above and I am still unclear as to the placement(s) of the chassis ground wiring? I plan to build a system similar to yours except without the alternator portion (i.e. only shore power and solar to charge LiFeYPO4 battery). In my wiring diagram all the negative (black) wires, as in your wiring diagram, come back to the negative bus bar –> then lead to the negative terminal of battery. In your diagram I see wire to the ground chassis leaving the negative bus bar. Is this ALL that is needed? My inverter/charger (Xantrex Freedom XC 2000) also calls for a DC ground in addition to the negative DC cable. Is this necessary? I see you do NOT have a DC ground from your inverter (Victron unit).
How is the ground chassis location chosen and connection made? I.e. where exactly does one drill into the vehicle frame. How is the surface prepared (I assume remove paint) to ensure an appropriate connection? Then simply bolt a lug into the frame?
thanks!
You can make that ground connection to anywhere there is metal. We, personally used the wheel well. Just a bolt through with the paint cleaned off. Once we installed the lug and wire, we repainted over the top of it to seal the metal from rust.
If your busbar is grounded, you can then ground the boxes of all of the components that requires it to that busbar. So, the busbar is grounded, then each of the negatives AND ground wires will also run to that busbar.
Hi Nate, thanks for the very thorough diagram and other insightful blog posts! I’ve purchased nearly all the components but have a questions about the wiring quantities. For example, the Red 2/0 wire is listed twice; once as 5ft and again as 25ft. Is this correct? You’re recommending 30ft total and this is the best method to purchase that quantity?
Oops! I tried to consolodate all of the wire lengths, but yes. Just buy 30ft of it and cut as necessary.
Hey Nate,
Thanks for this great resource – I have it bookmarked as I work on a Dodge Campervan conversion (with solar and poptop!). My setup will be modular, so that I can remove water, solar, battery(lithium)/inverter and fridge ‘modules’
so I can use it as a full passenger van without campervan bits getting in the way.
I wondered if you had any insight on how to leave currently wired 12v outlets (there are a few front to back, some of which are only powered when the engine is running). Do you think it is possible to make them switch over to the battery system? The Li-BIM wiring diagram from Precision makes it look like this might be possible, although I’m guessing there will need to be a double pole rocker switch somewhere to make it happen.
Otherwise, do you know if there is a way to use the ingnition cable (used by alternator and Li-BIM) from the motor to enable automatic switching for my setup?
I’m guessing you’re otherwise going to say take all the 12 outputs off the main battery and put them on the coach battery. I can’t do that because the build will be modular, and the battery won’t always be there. I realise this means quite a bit of double wiring/fusing.
Apologies if this is a rather silly question, but I’m finding it rather vexing!
Also wondering if you have experience of upgrading alternators to increase charging capacity.
Nate
I have gotten your system and installed it as specked. All was great.
How ever I have had a little bit of trouble with the LI_BIM 225 isolator charging off the truck. Your diagram showed the alternator cable going to the coach side of the isolator. I down loaded the quick guide from Precision circuits and they show the alternator cable going to the chassis side.
I receive no reading of volts-watts coming into the smart controller either way I wire it. My ignition wire is only hot when the veh.is running. I have not hooked up a manual switch as of yet.
Most of our diagrams should be treated as ‘rough’ in terms of wire placement and do NOT superscede what’s in the manual or marked on the unit itself. Sometimes, the pictures I have may have the positive and negative flipped from what’s actually on the product, so it’s VERY important to do your due diligence in this regard and follow manufacturer recommendations. Chassis = Alternator, Coach = House Batteries.
The manual switch is not 100% necessary, it’s just to force-combine the circuit in case you need to emergency jump your start batteries from your house batteries. Also, if your house batteries are higher than 13.4, the isolator will not combine the banks.
Once you get those wires in the correct place, I’d recommend going for a drive with your VictronConnect app pulled up and on your phone and mounted to the dash to see if there is charge coming in at any point.
My tech support is fairly limited when it comes to troubleshooting that particular device. I’d highly reaching out to Battle Born and they should, at the least, be able to point you in the right direction on that one.
Hi Nate,
Looking to do pretty much the same set up as in your interactive diagram. The only different things will be that’ll be hooking into my RV’s main breaker box, and I’m using a 300 ah lithium battery bank, and probably wiring my solar panels in parallel series groups. I also have the 150/35 victron charge controller.
Can I just follow your diagram as is, or will I need to size up some of the breakers/fuses?
Thanks
Hey Mark!
You’re going to need to change quite a few things from the diagram you’re mentioning. We will be rolling out new wiring diagrams soon, but in the meantime, I think some of the articles you can find on this page will get you started with designing your own system to your own specs: https://www.explorist.life/diy-campervan-solar
Cheers, Nate. One more question: When doing the install on your mum’s truck camper, were you able to wire the 2 awg DC wire from battery positive directly into her camper’s DC fuse/breaker box? Like, did it fit without having to reduce the size?
Thanks!
I truly do not remember one way or the other and I hate to make a guess on that, so you’ll just have to check it out on your own setup.
Is there a reason the chassis grounding wire is so thick? 2/0 seems like a lot. The rest of the chassis grounds are no where near that large.
I love the diagram and my set up is exactly like it.
The ground needs to have the capacity to carry the max capacity that the biggest device in the system can produce. So, for example… If the Inverter calls for 2/0 wire, the ground needs to be 2/0.
Also, the 2/0 from the busbar to the ground is the return loop for the alternator charging, so it needs to be adequately sized to carry alternator current as well.