Interactive DIY Solar Wiring Diagrams for Campers, Van’s & RV’s

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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

If you are looking for old wiring diagrams you can find those here:
https://www.explorist.life/solarwiringdiagrams-archive/

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

Watch the Video Below to Learn How to Best Use These Diagrams:

Here are the current options for our solar wiring diagrams and parts lists. If you don’t see one that fits your needs, there are options available for custom wiring diagrams here: https://www.explorist.life/consulting

Not sure what size you need? Start with a power audit here: https://www.explorist.life/what-size-of-solar-system-is-needed-to-power-a-camper/

217 thoughts on “Interactive DIY Solar Wiring Diagrams for Campers, Van’s & RV’s”

  1. 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!

    1. 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.

      1. 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.

        1. 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.

  2. 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!

    1. 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.

      1. Hi, Nate! Also thinking about the Yeti, but I really want to be able to charge from the alternator. They keep saying they are going to put out an alternator charging kit, but it’s been “unavailable” on their website for ages. They do have a ‘cigarette-style’ charging cord available, but am I right in assuming that this would charge the battery much, much slower than using a b2b style hook-up?

        1. The Yeti “Link” is the item you’re looking for. It’s not available on amazon, but it appears to be available on their site.

        2. As per your diagram for shore power to inverter AC side input you go directly from sure right into input on inverter with not breaker in between. Can you explain why you don’t use a breaker panel incoming like the outgoing side. I’m a bit stumped as to how I should safely install my pure sign wave inverter. I see you rocking FD shirts on some of your YouTube vids. Brother fireman here if u are.

          1. The breaker for shore power will be found in the campground power pedestal or in the breaker box in the wall the shore power is being plugged into. So, it is indeed protected, but it’s not a part of the camper wiring. Same reason there is no breaker on the wiring of, say, a toaster or a vacuum.

    1. 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.

  3. 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!

    1. 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

  4. 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.

    1. 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.

      1. Hi Nate! Thanks for taking time to put these together! It’s been the most helpful tool I’ve been able to find so far. My only question is, where the fuse box for 12 volt items like LED lights? Am I overlooking it or was it left out or incorporated in a different way? If I wanted to add the standard fuse box a lot of people use Would I just use 2/0 gauge wired for the positive and negative input? And 12 gauge for the appliances?

        Thanks
        Jas

  5. 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?

    1. 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.

  6. 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!

    1. 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?

        1. 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.

  7. 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

    1. Hey Evan! Glad it’s helping!

      I’ll just run down your list 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?

      There will be a breaker protecting that line in the power pedestal or the wall you are plugging into (Think household breaker box).

      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?

      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

      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).

      Mainly because I can’t find a reliable source with adequate reviews on a 250 amp resettable breaker that I really liked. :/

      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.

      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!

  8. 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?

    1. 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!

  9. 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.

    1. 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!

    1. 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.

  10. 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

    1. 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.

      1. 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?

        1. 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.

  11. 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.

    1. 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.

  12. 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?

    1. 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.

  13. 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.

    1. Hi Nate
      Need your help I have 300 watts solar panel renogy 40amp charge controller and battleborn lithium battery what are the parometer setting second what is a good isolator to charge my battery my van is ram promaster 2500 Third I have a renogy 2000 inverter mistake did not get inverter charger what can I do to use Ac units at home

      Thank you

      1. Here is a link to the Battle Born charging paremeters: https://battlebornbatteries.com/charging-parameters-chargers-recommend/

        A good isolator for Lithium: https://battlebornbatteries.com/shop/lifepo4-battery-isolation-manager/?afmc=explorist_bb67

        Re: Inverter… I VERY much like an inverter/charger, but ultimately that’s up to you with what you were hoping to accomplish with your system. If you never will need shore power, an Inverter by itself will be fine.

  14. 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

    1. 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.

  15. 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

    1. 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.

  16. 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?

  17. 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?

    1. For that, you’d simply be installing the panel(s), charge controller, wires and fuses and hooking directly to the battery/busbar.

  18. Lynn Forschler Barnidge

    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!!!

    1. 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.

  19. 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!!

    1. 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.

  20. 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!

    1. 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.

  21. 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.

    1. 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.

  22. 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

    1. 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?

  23. 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.

  24. 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

    1. 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

      1. 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.

        1. 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.

  25. 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.

    1. 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.

  26. 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.

    1. 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.

  27. 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.

  28. 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.

    1. 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/

  29. 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

    1. 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.

  30. 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?

  31. 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

  32. 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!

      1. 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.

    1. 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.

  33. 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.

      1. 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.

  34. 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?

  35. 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!

    1. 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.

  36. 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.

    1. 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.

  37. Michael Krisinger

    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!

    1. 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.

  38. 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?

    1. Oops! I tried to consolodate all of the wire lengths, but yes. Just buy 30ft of it and cut as necessary.

  39. 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.

  40. 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.

    1. 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.

  41. 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

    1. 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

      1. 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!

        1. 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.

  42. 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.

    1. 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.

      1. I have been using your diagram to set up my system…very helpful. I had similar question about the chassis ground wire size so appreciate your response. My next question is as follows: if I ground the inverter box to the negative bus bar and then run a 2/0 cable to the chassis can I attach that chassis ground to the existing chassis ground (where the 8 gauge bare copper chassis ground from the AC panel is attached)? It seems like this would be okay but want to make sure I am not creating some sort of circuit by attaching both to the chassis. Thanks and love your site!

        1. The ground wires required are noted in the wiring diagram. Additional ground wires are not necessary.

      2. Your wiring sizing for grounds for both the inverter and solar controller isn’t exactly correct. While using bigger wire won’t hurt anything, you don’t need big wires for this. Those ground connections are safety grounds from the metal on the devices themselves not DC grounds. So if by chance the inverter or solar controller becomes energized you wont get shocked. It also helps reduce RF noise that could impart TVs and other electronics nearby. I simple 10 or 12 gauge would work fine.

        1. Jay. The ground size wire choices in this diagram are based on ABYC code. Although it’s unlikely you’d get shocked if an internal short were to happen; the chassis then could be carrying the full short circuit current of the battery resulting in catastrophic meltdown with improperly sized chasses grounds.

          Again… my wire size choices are based on ABYC code:

          “Install a DC grounding conductor sized not less than one size smaller than the DC
          positive conductor and have a capacity such that the DC positive fuse has an amperage
          rating not greater than 135% of the current rating of this grounding wire. As a
          practical matter, this wire will be much larger than the AC grounding conductor. This
          requirement is the latest addition to the standards when it was discovered that faults in
          the DC side of an inverter or charger could provide sustained high currents that could
          start a fire from overheating the AC grounding conductor.”

  43. Nat, Love your info and your page! Do you have a 24v alternative diagram? Looking to setup a trailer that has more 120vac equipment and 24v inverters are way more efficient. Thanks in advance.

  44. This is really awesome. I had already bought my gear and spec’d most of it out, but was looking at different diagrams before I start actually installing anything when I came across this. I love the layout and you are running a very similar setup to my stepvan build.

    My only question is about the wire gauges you chose for the smaller stuff. The MaxxFan only tested at 2.5A on 10 and the LED lights are a lot less than that. Did you NEED 12 awg wire, or was it just easier to run one size?

    I had orriginally spec’d 14 awg for my fan and LED’s and was going to use 4 awg to my fuse box (supports 60A @ 20ft).

    I have a 400w Renogy solar running the 40A MNPT controller with 400ah AGM (2 x 200ah) betteries, 200A isolator, 175A alternator with 2 drive batteries.

  45. I think I have posted my question in the wrong place. I will try again here and hopefully you can amend accordingly

    Great content. It will be helping me a lot in my build.
    I wonder if you have got/ will get a chance to cover plumbing in your campervan. I am eager to find out what sort of pumps/gears you used. Many thanks

  46. Planning a 200 amp hour Battle Born, 200 watt or so system for our pop up camper. Max daily usage approximately 55 amp hr (12v frig, heater, lights, fan, charging accessories). Will only be using AC to charge laptop/phones, maybe run a blender so thinking of using a Progressive Dynamics Charger/Converter (not sure what size is best) instead of the 2000 watt inverter. I assume the converter would just replace the inverter in the diagram and the rest would remain the same. Would appreciate you pointing out any flaws in my thinking.

    1. There would be a bit that would need to change and I pretty much never recommend using a converter instead of a inverter charger as it makes for more wiring. Feel free to do that, but don’t assume that my diagram will be accurate if you start changing components.

      1. Hmm, thanks for your input. Not sure what other options I have. I don’t need a 2000 AV inverter for anything. Maybe a lower watt inverter charger or just a straight charger? Don’t see us plugging in much on the road accept when solar gets behind. I must say I have learned a ton from your site, but have more to learn,
        Thanks, Stan

  47. I know you said you’d show the wiring for the (2) fans in that install video, but I can’t find it anywhere and the chart only shows one. Did you wire them separately or are they on the same line from the fuse block? In my head, it doesn’t matter, as running them parallel saves wire and the power is still available from the 1st fan to 2nd even if the 1st isn’t running. Is this correct?

  48. Hi Nate,

    thanks a lot for the great resource – very useful.

    Quick question in comparison with the old diagram: Why did you use a double poled circuit breaker (instead of single) on the solar panel-charger wires? Is the neutral side not redundant (unless you’re worried about pole reversal)?

    Cheers

      1. Hi Nate. Your videos, diagrams and content as a whole are absolutely outstanding! Truly top-notch! Thank you! Quick question: the 2-pole PV breaker you have linked in your diagrams isn’t currently available. Can you point us to a suitable replacement? I can’t seem to find one with the exact same specs.

        Also, although it may not meet the AYBC code, would placing a single breaker (e.g. a Blue Sea C-Series toggle breaker), placed inline of the positive lead from the solar panels be sufficiently safe?

        Thank you again, so much!

        1. The PV breaker should now be updated inside of the diagrams (not the lists, yet)

          Re: Single pole breaker… You can use whatever you like, but I do make these recommendations for a reason. 🙂

  49. Nate,
    In your earlier diagrams you had the battery positive from the solar controller to the posit bus bar after the battery cutoff switch. Looking at your new diagrams the positive lead has been moved to the battery side of the cut off switch. I understand that this allows the solar to continue to charge the battery even if you’ve cut power to the rig. Is there any other reason or benefit in making this change? Thanks

  50. Hi Nate,

    Could you recommend an alternative to the “LANGIR 500VDC 2P Solar Photovoltaic Din Rail Non Polarized DC Circuit Breaker Control Circuit C Curve With TUV Certificates (15A)”? That item is out of stock.

    Thanks!

  51. Hi Nate, thanks for sharing all this incredibly helpful info! One question about the breakers on the AC side of the new diagrams. When I click on the amazon links for those AC breakers, it takes me to a product that is clearly a DC breaker. Is that right, or can/should those breakers be AC-specific? And the 50A AC breaker appears to be a 2-pole breaker (but the amazon link is a single pole DC breaker). Should that one specifically be 2-pole, or is 1-pole ok?

    1. Products have been switched around on amazon. I’m working on changing them around; but yes… AC circuits need AC breakers.

    2. I’m having a hard time understanding how the bus bars are connected and how to incorporate the copper plate. Do you have a more detailed outline of those connections? Or a video?

      1. Not yet. Working on it. 🙂 Be sure you are subscribed to the email list and I’ll send an update when it’s complete.

  52. Thank you so much for making this. It’s great!

    I’m in the process of building my system and plan on buying components over time.
    I was thinking of purchasing batteries later and running my 12v lights and sockets off 12v output of the charge controller. It looks like i’m within the amp rating.
    Any reason this wouldn’t work?

    1. I think the main thing I can see that not working on is that you would have no power when the sun is down.

  53. Hi! As everyone above has noted, amazing stuff. Quick question – how did you mount/house the 15A breaker? Did you get an actual breaker box of just leave it out in the open and screw it to the wall?

    Thanks!

    1. It’s mounted to a “Din Rail”. Look for the “Din Rail” in the shopping list below the diagram.

  54. Do you happen to have a wiring diagram for 200 watts of solar with 100 AH lithium battery? Im only building a DC system. trying to keep it simple. I was using the 300 watt diagram as a reference but I get lost when it comes to the fuses and required wire gauge.

    1. You can use the same sizes wires and fuses from the 300w system on a 200w system. They will be slightly oversized, but there is no harm in that.

  55. Nate,

    First off thank you for putting all the time and effort into making these diagrams and videos. I recently bought all of the materials on your list to do a solar build in my 98 Roadtrek 190P. The updated diagram looks much better, however I had based my build on the last iteration (the one with 3 disconnect switches). I do have screen shots and have been piecing it together based off of those, however it would be super helpful to see a more detailed version of the last diagram. Would this be possible?

  56. My needs are much smaller as I am building a 5×8 cargo trailer conversion that should only be off grid for 2 nights max or otherwise be plugged in.

    I am having trouble downsizing the diagram to my 100 watt solar with a 125 Ah battery.

    My peak usage which would be during sunny days, because of the heat, would be 106 Ah per day.

  57. Vincent Bergeron

    Hey! Great stuff! Can you give me the link to the 15 Amp Solar Disconnect Switch. It seams to not working anymore from you list.<Thanks

  58. In the process of hooking up all of the stuff on your diagram (300 watts solar, 200 ah batteries). One question. I don’t understand how to hook up the Dinkle solar gang box. Do I need two boxes? One for ground and one for neutral?

    Been following you since the Adventure in a Backpack days. The evolution has been fun to observe. Good job.

    1. I’m working on an easier solution for this as I’ve been getting a ton of questions for it. Stand-by.

  59. Do you not need to ground the 110 system? Is the 2/0 gague coming out of the inverter to the bus bars grounding that system? Or does the breaker box need to be grounded?

    1. 120v grounding is taken care of inside of the inverter (At least the Victron Multiplus. If you’ve got a different inverter in question, consult the installation manual) and all ground wires for this setup are shown.

  60. Hya Nate & EXPLORIST.life

    Thanks heaps for all your great content. Three quick questions:
    (1) Are above ‘Solar W’:’Ah Battery (bank)’ arrays recommended ratios, that is, rules of thumb when calculating one’s power requirements?
    (2) Given that I’m in Switzerland (230V, 50Hz), do I need to half the numbers for fuses, breakers & wire gauges – with respect to formula
    [Power = Voltage x Current] –> Amps = Watts / Volts?

    I’ll certainly come up with more questions soon.
    Lemme know how I can repay the service.
    I’ll definitely add your entire playlist to my ‘RE(in)VANnPTION’ channel in due time.

    Regards,
    Sandro

    1. The systems above are some of the more commonly sized configurations I’ve been asked about, so yes, they are recommended ratios. To calculate power requirements, though, I’d recommend performing a power audit which you can find a tutorial for, here: https://www.explorist.life/what-size-of-solar-system-is-needed-to-power-a-camper/

      For 230v, everything could stay the same except the inverter. You’d just want a 12v to 230v inverter. Victron makes these as well.

  61. Hi Nate, When plugged into shore power, does the systems above automatically know and run your appliances off the outlet directly? Or is it charging the batteries which are still running all the appliances in the van? Is there anything you need to do when you plug in? i.e turn off the main disconnect switch or toggle anything on the inverter/charger itself?

    Thanks,
    David

  62. Hi Nate, I was wondering if you have a pure DC set up instructions set? I will just have a very simple set up with 12V fridge, lights, etc. Thanks. Karen

  63. Hi Nate we spoke at the van expo in Dillon. I am looking at running 2 100 w panels to charge my house batteries in an RV. I have 2 6v batteries that are daisy chained together. Looking at your diagrams do I run the positive and negative wires from the charge converter directly to the bateries? Thanks

  64. Hey Nate or anyone,

    I have my whole D/C and solar set up and was testing out the main disconnect which works in shutting the power off from the battery.

    My issue is when I turn the main disconnect back on I have a low voltage output from the battery (1.5-3v) and nothing can turn back on.

    If I disconnect from the battery and reconnect I read 12v from the battery again.

    Any ideas what I am doing wrong?

    Thanks in advanced!

  65. Hello Nate! Great material! The best there is in the internet.
    I read all comments but still have a doubt on the limits of such a system. I am building a motorhome and my electric project is considering solar panels totaling 400W, a 3000 to 4000W inverter and two 190A stationary batteries each. The fridge will be 12V. My question is regarding the use limitation of for example a 2000w electric induction cooker? Or a 1500w electric fryer?

    From what I researched the current will not exceed 20A because this is the recommended circuit breaker.

    Is it possible? How long will it last?

  66. hi..
    I am looking for a 12 dual battery bank switcher.
    The idea is that bank A would be the primary. As voltage drops below a certain level, the switch automatically flips to battery bank B. Once Battery bank A voltage goes up above a certain voltage, then the switch automatically switches back to battery band A.
    Ever come across such an item?

  67. Hi Nate,

    You provide a great source of information; thank you for that.
    I see in most of your schematics that you wire the solar panels in series (rather than parallel). Is there a particular reason for that?

    Thank you!

    1. The ‘actionable’ differences are: Battle Born is out of Reno Nevada, so when you need support, you’ll be able to get ahold of them easily. Battle Born also has a 10 year warranty on their batteries. Battle Born also supports me and this channel which allows me to put out all of the free-to-you information I provide. There are loads of differences within the actual lithium cells and the BMS, but if you REALLY like; you can dig through the spec sheets however detailed you’d like to get. I’ll leave that up to you though.

    2. I considered batteries like that, Rodney. They’re about 30% cheaper, but what I’m really drawn to is how small their foot print is. I’m a little suspicious. The 12V100AH with BMS option weigh in at 10kg each. That’s at the high end of specific energy for LiFePo4 batteries. And that doesn’t factor in the weight of the BMS.

      LiFePo4 is one of the safest chemistry, so I’m not too concerned about fires.

      But at the end of the day I decided I don’t want to be the guinea pig. If other people have good success with these batteries, then I’d use them. I just don’t want to be the one rolling the dice.

      Source: https://batteryuniversity.com/learn/article/types_of_lithium_ion

  68. Hey Nate,
    thanks for the great blog, it really helps a lot to get into the topic 🙂

    My planned project specs: 1 panel 180W; MPPT 75/15; AGM 100-150 Ah; no AC needed. The MPPT 75/15 has additional load connectors. In your diagram ‘300W Solar | 200Ah Batteries’ the loads are connected over the switch directly to Vbat+(no connector on the MPPT controller).

    Question a) Would you recommend ignoring the Load connectors on the MPPT controller and install the system like you showed in ‘300W Solar | 200Ah Batteries’? If not, cables/fuses between Battery and MPPT must able to support peak power of the consumer devices, correct?
    Question b) Can you explain the 15 A Solar disconnect? Why is necessary, what could go wrong?

    Thanks again for the great blog and your videos.
    With kind regards,
    Felix

    1. Hey Felix! I would, indeed, totally ignore the ‘load’ outputs on that charge controller for your purposes and just wire the same way as listed in the wiring diagrams you’ve found. If I may, though… make a recommendation to use 2 panels instead of just 1. Consider using two, 100 watt panels instead of 1, 160 watt panel as the MPPT will be able to work better off of the increased voltage.

      The disconnect is required by ABYC code for ungrounded solar arrays and is simply there to cut power from the panels in case of unforeseen malfunction or maintenance.

  69. This is an awesome resource. Thanks so much for putting it together. I do find the page difficult to navigate because I can’t hide the other options. I wish each option (e.g. 525W solar, 300AH batteries) where it’s own page. I keep getting confused!

  70. Chris rondestvedt

    Hi Nate

    Read through all…impressive!

    A truly basic question…which type of controller do you prefer, PWM or MPPT?

    Thanks

    Chris

  71. Hey Nate, thank you so much for the detailed information, your blog is incredible!

    I am trying to use your link “CLICK HERE TO ADD ALL AMAZON PRODUCTS TO AMAZON CART” for the LI-BIM and all of the additional parts needed and the link is broken, only adding the Momentary switch to Amazon. I want to let you know, since I want to use your affiliate links to say thank you, for providing such detailed information.

    Really appreciate the work you put into your site to help others!

    Thanks,
    Kevin

    1. Hey Kevin! It’s doing that because that’s the only part available to purchase from Amazon in that section. The Li-BIM is included in the Battle Born Kit and all of the other fuses and wires are totaled up at the bottom of the parts list.

      1. Makes sense, just wanted to make sure so you guys get the credit that you deserve.

        One more question for ya, for the AC Shore Power set up, your diagrams show a 10/3 romex wire and a 6/3 romex wire. What’s the reason for using a 10/3 vs a 10/2 and a 6/3 vs a 6/2? I’m struggling to find more information on this.

        Thanks again!
        Kevin

        1. “10/2 w/ Ground” & “10/3” & “10 Gauge Triplex” are all, pretty much the same thing. It just depends on what the manufacturer decides to call it. They all have 3, 10 gauge wires inside them.

  72. Hi Nate! I’ve seen you recommend a 175w Newpowa solar panels. They have a dimensional drawing that says those are over 58″ long. Without a roof rack, the OEM sprinter rails can really only accommodate ~51″

    I tried the Richsolar 190w panels that are ~58 3/4″ wide and even fabricated custom mounting brackets. I hated the look of them hanging over ~2+” on either side and the sides flare about above the roof rails toward the front, so the bracket ends up resting on the painted van (rather than the rail) which is no good.

    I guess most people mount them on crossbars that are mounted to the rails? That raises them up quite a bit and probably causes a fair amount of drag which decreases gas milage.

    1. Oh, after writing that I realized if I bolt the two Richsolar 190w panels together and turn them sideways then the width of the double panel is about 53.6″ which fits perfectly on the OEM rails.

    2. We have the 175w Newpowa solar panels on our van and are fine with the overhang. I recommend that everybody take measurements of the solar panels and verify they will work for your own needs.

  73. Nate

    Late Spring 2020 is when I will have our new Transit AWD van. For our power needs I’m looking at GZ Yeti 1400/3000 unit to power the van. I’ve seen a few videos that show the basics how to Integrate the GZ using a 12v fuse block, setting an outside shore power connection and connecting the car power using their Charging Link. How do I contact you when I’m ready for a custom wire diagram and a consult?

  74. I join the chorus of thanks from those above for your excellent diagrams and your willingness to answer questions.

    One thing I am wrestling with is the need to run individual negative wire runs back to the DC distribution centre. The negative bus of the distribution box is connected to the main negative busbar and then to chassis ground. I have about 10 dc circuits going from the driver side where my electrical closet is to the passenger side where the kitchen is. I was thinking of consolidating all my negative runs to a passenger side negative busbar terminated to a passenger side chassis ground.

    I may be very naive, but I am not seeing a downside to this – less total wiring and number of connections. I am not sure if the ground conductor composed of the chassis sheet metal would introduce appreciable resistance vs a properly sized copper wire back to the distribution centre bus.

    Many thanks!

  75. Hi Nate, how are you? jus a quick question, we are using your spreed sheet for the power audit, but we are in Australia, so our appliances are 220, how do we do? any way to change it ? thanks!!

  76. Hi Nate,
    I have 4x100W Solar panels and 300Ah of LifePO4 Batteries. One major change for my system is that I have a 3000W inverter (due to a lot of Watts coming from an electric water heater). So with a 3000W Inverter (9000W @1s, 4500W@3s, 3600W@10s) do I size the fuse for the continuous 3000W (3000W/12V=250A) or for maybe 3s Surge 4500W/12V=375 rounded to 400A. I dont see the continuous Amp draw of the water heater plus other draw that may be running at the same time (120V mini fridge, Small 300W blender, etc) exceeding 3000W. A lot of generic sizing online suggest 400A Fuse with 4/0 wire for a 3000W inverter. At 3000W 250A fuse and 2/0 wire could work but at 4500W a 400A fuse with 3/0 (385A max is cutting it close to 375A) and max surge is 9000/12=750A which max’s out ANL Fuses and exceeds 4/0 wire max amps. So do you size your fuses and wire for the rated output of the inverter or for the surge and Do you ever size fuses and/or wire off of max possible surge.
    Best regards,
    (Apologize for rambling)
    Jay

  77. Trying to fit the maxium solar on my van (the vent breaks the space up). Question: Is it not advised to use different size panels?? Also, is it best to stay with the same brand? Do not see this addressed anywhere on your site. Thanks

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