Want to build a robust, high-quality, off-grid camper van electrical system? You’ve come to the right place! In our 2+ years of van life, our van’s electrical setup has supplied us with reliable, consistent power regardless of the wide range of environmental and location factors we’ve thrown at it.
Our van’s electrical system has:
Want to know how we built our van electrics?
In this page, you will find everything you need to build your own robust, off-grid electrical system for your camper van.
This DIY camper van electrical system guide will teach you how to:
There is so much to learn and great skills to pick up but it’s important to go slow and thorough.
Oh, and all the information here is 100% FREE!
So if you’re ready, let’s get started!
Camper Van Electrics Overview
What Do You Want From Your Setup?
Whether you only desire to build a modest electrical setup or you have dreams of constructing a luxury, off-grid electrical system, it’s important to do the proper research and homework beforehand.
In the following sections, you will learn how to plan and build your own electrical system. Below is exactly what we will cover in this article:
By the end of this electrical guide, you’ll have a solid understanding of what you need, how to construct, and how to maintain your very own camper van electrical system.
Which Devices Do You Want In Your Van?
Before you can begin figuring out what batteries or solar panels or any other components you need to buy, it’s important to decide which electrical devices you’d like to have in your van. Of course, the more devices you want to install, the bigger and more complicated your electrical build will get, and the more expensive it will be.
Below, are 9 of the different electrical devices we installed in our van.
LED Puck Lights
Installing LED puck lights in your camper’s ceiling is a great way to brighten up your van’s interior when natural sunlight isn’t sufficient. Surprisingly, we turn on our puck lights much more often than we originally thought. Whether it’s during the evening, early mornings, or even on cloudy days, our puck lights ensure there is enough ambient light inside our van.
Read More About How We Planned & Installed Our Puck Lights:
A roof vent fan is practically a must when living and traveling in a camper van. Vent fans not only help to bring in cool, fresh air and expel stale air, but they also help to regulate the internal temperature of your van and get rid of greasy smells when cooking. We leave our vent fan on 90% of the time. Best of all, if you choose the MaxxFan, the product comes with a build-in rain cover so you can even use the fan when it’s raining, which, from out experience, is crucial.
12v Fridge (Electric Coolers)
A 12v fridge is an under appreciated electric device in many camper conversion builds. Good quality RV fridges aren’t cheap and can take up valuable space inside a van. But having a fridge is practically a necessity when planning to live and travel long term in a camper. Compared to cheaper coolers, having a proper 12v fridge keeps your food cool 24/7, eliminates the need to look for ice every 2-3 days, and allows you to boondock in the countryside for much longer periods of time.
Installing a diesel heater in a van is a luxury item, but it’s amazing how well they work, how fuel efficient they are, and how comfortable they can make winter van life. For two days we were stuck at a campsite in Grand Canyon National Park after 2 feet of snow fell all around us. While temperatures dropped to 9F (-13C) at night, we were warm & toasty inside. Our diesel heater has also made getting up in the mornings so much easier because with just a push of a button, our van heats up in minutes.
120v Inverter / Charger
Generally, the batteries you install in your van will distribute power in 12 volts. So if you want to run standard electronic items like your laptop, hair dryer, Instant Pot, or even an electric toothbrush, you’ll need an inverter to take the 12v from the batteries and output power in 120v. If you get an inverter/charger combo, like our Victron 200VA Inverter/Charger, you will be able to charge your house batteries using shore power, if sockets are provided at campsites and RV parks. The usefulness of an inverter really depends on what you want to power. If you only want to power devices that demand less than 300w, a portable Bestek 300w Inverter may be more appropriate for you.
USB & 12v Sockets
Having at least one pair of USB & 12v sockets is invaluable for van life. With sockets like these, there are so many different electrical devices that you can power. From your smartphones, to 12v fans, 12v fridges, 12v propane detectors, cameras, portable inverters, and even 12v air diffusers; the list is endless. We’ve installed 3 pairs of these USB & 12v sockets throughout our van and they are constantly in use.
A water pump is definitely a luxury item when it comes to van life but we installed one anyway because we wanted our camper van to feel more like a real home with instant running water with just a flick of a switch. If we could build a second van conversion, we would 100% install a water pump again, but we’d stop short in saying that a water pump is a van build necessity.
12v Reading Lights
We installed two 12v reading lights on either side of our bed because we thought we’d often be doing late night reading. In reality, we don’t use them for reading. Instead, we turn them on for softer ambient lighting at night and when one of us has to get up in the middle of the night to use the bathroom. These “reading lights” are cool little devices that work great and are high quality, but they, too, are definitely a luxury item.
Conclusion: Create Your List Of Electrical Devices
Once you know which electrical devices you want to install in your camper van, it’s a good idea to write them down in a list. You’ll need that list when selecting your house batteries.
Select Your House Batteries
The batteries that power your electrical devices are the foundation of any camper van’s electrical system. These batteries are typically called “house batteries”.
Not only do these house batteries provide electricity when you require it to power your devices, but they also absorb and store electricity for later. Getting your battery situation sorted out is one of the most important parts of your van’s electrical system build.
In this chapter, you will learn:
- The different types of battery technology in the market today, and
- How to properly size a battery bank that meets your daily electrical needs.
AGM Vs. Lithium-Ion Batteries For Camper Vans
Tried & Tested vs. The Fancy Newcomer
One of the biggest questions you may have when choosing your house batteries is which ‘type’ of battery to select: AGM or Lithium-Ion?
Unfortunately batteries are not all the same and each type has their own benefits, drawbacks, and even their own unique charging quirks.
When selecting the type of batteries you want, it’s important to think about the following points.
The biggest difference between AGM and Lithium batteries is their initial cost. Lithium batteries often cost 3-4x more than their AGM counterparts.
Energy Density (aka weight)
Lithium batteries are considerably lighter, often ½ as much, as an AGM battery for the same number of amp-hours.
Practical Usable Energy
To maximize the lifespan of an AGM battery, an AGM battery should ideally not be regularly discharged more than 50% of it’s available capacity. Lithium batteries can often be discharged well past 90% without major consequences to their lifespan.
Even with proper maintenance and care, an AGM battery has an average of 1,200 cycles in it’s lifespan. And this is under perfect conditions, which rarely occur. Lithium batteries have a lifespan of ~4,000 cycles.
Traditional AGM Batteries
Based on our own needs and budget, we purchased three Lithium-Ion batteries and they’ve worked perfectly for our trip. After over two years on the road, our batteries have never failed us.
How To Properly Size Your Battery Bank
Camper vans with undersized battery banks is one of the most common mistakes we see when we meet other van lifers. They either don’t have enough battery (amp-hours) to power their devices at night or they’ve discharged their batteries too far for too many times that they end up with a prematurely dead battery and are forced to purchase new batteries while on the road.
Properly sizing a battery bank for your camper van is a two step process.
1. Figure out your daily energy usage:
This involves already knowing which electrical devices you want to run in your van and for how long each device will be on per 24-hour period. When you add up the energy demand for every electrical device, you will be able to estimate your ‘daily energy usage’.
2. Decide which battery type you will use:
Because of the difference in practical usable energy between AGM and Lithium batteries, your decision of which battery type to go with will affect how many batteries (how many amp-hours) you will need to carry in your van. Generally speaking, if you go with AGM batteries, you will need to carry roughly twice as many batteries (or amp-hours) as you would if you go with Lithium batteries.
Calculating your camper’s house battery bank size is such an important step that we dedicated an entire article to teaching you how to do it.
Camper Van Batteries Conclusion
By the end of this section, you should be able to properly select which type of battery you want for your van’s electrical system and to accurately know the size of your battery bank (aka how many amp-hours you need) that will be able to meet your daily energy usage.
Now you are ready to start Step 3: Solar Panels For Camper Vans.
Solar Panels For Camper Vans
There are several different ways to charge your house batteries and installing solar panels on your van’s roof is one of those methods. While installing solar panels isn’t a requirement for your van conversion, we believe harvesting energy from the sun is the most important way to charge your house batteries.
Why Solar Is Important For An Off-Grid Electrical Setup
Having the ability to charge your batteries from the sun vastly reduces your dependency on shore power and allows you to boondock out in nature for much longer periods of time.
Campers without solar panels would be forced to drive every 2-3 days just to charge their house batteries. We’ve seen it…
Learn More About Solar and Camper Vans
If you consider yourself a novice when it comes to solar panels for camper vans, fear not. We cover everything you need to know to properly select and install the right solar panels for your needs. Head over to our Solar Panels For Camper Vans article to get started.
In this article, you will learn:
By the time you finish reading Solar Panels For Camper Vans, you’ll have a great idea with how to move forward with installing solar on your van.
How To Properly Size Your Required Solar Array
Just like with house batteries, it’s important to properly size your ‘solar array’, which is a collection of multiple solar panels. This is important because without a sufficiently sized solar array, your batteries won’t be able to sufficiently charge enough by the end of each day in order to provide the required amount of electricity to meet your daily energy usage.
If you properly sized your battery bank, from the previous section, calculating your required solar array size is simple.
How To Size Your Solar Array For Lithium Batteries
Simply take the total number of amp-hours you calculated for your battery bank size and that number will be the total number of watts your solar array needs to be to sufficiently charge your batteries every day.
300ah of lithium batteries = 300w of solar panels
How To Size Your Solar Array For AGM Batteries
For those with AGM batteries, simply take the total number of amp-hours you calculated for your battery bank size, half the number, and the resulting number will be the total number of watts your solar array needs to be.
300ah of AGM batteries / 2 = 150w of solar panels
Build A Camper Van Electrical System
A Step-By-Step Guide
From installing your house batteries to connecting to your van’s starting battery, we show you how to build a sturdy and robust camper van electrical system.
For each step, we also provide intuitive installation diagrams to show you exactly how we put our electrical system together.
Get Our 100% FREE Electrical E-Book!
Download our electrical system e-book, which includes all of our installation diagrams for FREE.
Electrical Guide Chapter Contents
So if you’re ready, let’s get started!
STEP 1 : Connect Batteries Together
If you plan to have more than one house battery, you will need to connect them together. This is how to do it.
What You Need
What Gauge Copper Wire To Use
To connect house batteries together, we recommend using 2/0 Copper Stranded Wire.
In our van build, we bought 25 feet of both red and black wire and ended up using all 25′ of our red wire but only 13′ of our black wire.
Parallel vs. Series? Which Type Of Connection Is Best?
In most cases, you will want to keep your electrical system running on 12 volts. This is because, at least in the USA, most devices for campers run on 12v, instead of 24v.
Most AGM and lithium batteries will typically distribute 12v power. By connecting these batteries in parallel, you will maintain the entire battery system at 12v while increasing the overall battery bank size.
In order to wire our batteries in parallel, we would need to connect all our battery’s negative posts together and all the positive posts together.
Connecting The Ring Connectors To The Wire Ends
To connect the 2/0 AWG wires to the house batteries, 3/8″ ring connectors must be attached to each 2/0 wire end. These ring connectors will then bind to the positive and negative posts on each battery.
To attach a ring connector to the wire end, strip part of the wire housing to expose the copper strands and inserted the bare strands into the ring connector. Use a hammer crimper (and hammer) to crimp the ring connector onto the copper wire.
Connecting The Batteries Together With The Wires
Group your batteries together and connect each of the negative posts and each of the positive posts together with black and red 2/0 wire, respectively.
With all the movement and vibrations in our campervan, it’s important to get these battery connections super tight with a ratchet or adjustable wrench.
The Final Result (Fig 1.1)
After connecting the batteries in parallel, the result should look just like the diagram below.
STEP 2: Connecting Batteries To Bus Bars
After installing and wiring your house batteries in parallel, it’s time to connect the house batteries to the bus bars.
What You Need
What Are Bus Bars?
A bus bar is a metallic strip used for power distribution and collection and they usually come in pairs, one red and one black.
Bus bars make a wiring system cleaner since you don’t have to wire every electrical device directly to the batteries.
The Positive (+) Side Connections
1. Positive Terminal to Switch
Using the same 2/0 wire and 3/8″ ring connectors, connect one of your battery’s positive posts to the master on/off switch.
A master switch is useful to turn off your van’s electrical system for when you need to safely work on our electrical system or when you want to store your camper van long term and want to disconnect parasitic loads.
2. Switch To 300amp Fuse
3. Fuse To Red Bus Bar
From the fuse, connect straight to the red (positive) bus bar.
This bus bar will become the positive current collection/distribution center for your van’s electrical system.
The Negative (-) Side Connection
4. Negative Terminal To Battery Monitor Shunt
From one of the negative battery terminals take you black 2/0 wire and connect to your battery monitor shunt. The battery monitor serves two purposes.
1. Displays the remaining percentage charge of the battery bank.
2. Shows the instantaneous net flow of charge into, or out, of the batteries.
From the battery monitor shunt, you can connect to the circular user interface device with the supplied RJ12 cable.
5. Battery Monitor Shunt To Black Bus Bar
On the other side of the battery monitor shunt, take another black 2/0 wire and connected to the black (negative) bus bar.
This bus bar will become the negative current collection/distribution center for your van’s electrical system.
The Final Result (Fig 2.1)
After hooking up both the positive and negative battery terminals to their respective bus bars, your electrical system should look something like this.
STEP 3: Installing The 12v System
This section will teach you how to install a 12v system in your camper van.
What You Need
The Positive (+) Side Connection
1. Red Bus Bar To Circuit Breaker
Take your red 2/0 AWG wire and ring connectors and connect one end to the red (positive) bus bar and the other end to a 120amp Circuit Breaker.
This breaker protects your downstream 12v electrical devices from unexpected electrical surges.
2. Circuit Breaker To 12v Panel
From the circuit breaker, connect to the 12v distribution panel with another piece of 2/0 wire.
This distribution panel (fuse block) accepts the positive current from our batteries and distributes the charge to all our 12v electrical devices.
This panel also holds fuse blades to protect each 12 device from electrical surges.
3. Connecting Our 12v Devices
Connect the wiring of each 12v device to the distribution panel by crimping on heat shrink ring connectors to the ends of each wire end and activating the heat shrink with a heat gun.
Screw each ring connector to their respective binding post on the 12v panel and fit the appropriate fuse blades into each slot on the 12v panel.
The Negative (-) Side Connection
Simply took your black 2/0 wire with ring connectors and connect from the 12v distribution panel directly to the black bus bar.
The Final Result (Fig 3.1)
When completed, the 12v system part of your camper van electrical system should look something like the diagram below.
STEP 4 : Installing The 120v System
Installing a formal 120v system in a camper with built-in sockets throughout the van is a luxury choice and considerably more complicated that simply inserting a portable inverter into a 12v socket.
We opted to install a heavy-duty 2000VA Inverter/Charger in order to power more demanding electrical products as well as to be able to charge our house batteries with shore power.
What You Need
Connecting Inverter To Bus Bars
1. Inverter To Bus Bars
Take your red and black 2/0 wires with ring connectors and connect the inverter directly to the positive and negative bus bars, respectively.
To ground your 120v system, take a piece of 12 AWG Wire and connect the inverter to a ground point on the vehicle’s chassis.
Inverter To Shore Power
If you opted to purchase an “inverter/charger” combo, you have the option to charge your house batteries from shower power.
Even if you do not intend to stay at RV parks, having the option to plug into shore power is a nice capability and doesn’t require much extra work.
2. Inverter To Power Inlet
Drill a 2.5″ hole either in the side of your van’s exterior or inside close to your inverter and install a 15amp Power Inlet.
We drilled our hole into our back bench.
Take 12/3 stranded wire and connect the backside of the power inlet to the power input section of the inverter.
In our inverter, this is the “AC In” part.
Inverter/Charger to 120v Sockets
3. Inverter To Circuit Breaker
4. Circuit Breaker To 120v Sockets
Finally, coming out of the circuit breaker box, the 12/3 wire is then wired to all the sockets in the van.
The Final Result (Fig 4.1)
When completed, the 120v system of your camper van electrical system should look something like the diagram below.
STEP 5: Connecting Solar Panels To A Van Electrical System
Solar electricity in camper vans is such an important and vast topic that we wrote an entire article dedicated to Solar Panels For Camper Vans.
In that article you will learn:
Attach Solar Panels To A Van's Roof
1. Attach Z-Brackets To Panels
Attaching Z-brackets to solar panels is a straightforward process because rigid solar panels already come with prefabricated holes that you can attach your foot brackets to.
2. Attach VHB & Butyl Tape To Z-Bracket Feet
To prevent water leaks and to create a strong bond between the Z-brackets and our van’s sheet metal roof, we used a combination of VHB Tape and Butyl Tape.
The illustration to the right is the underside of a Z-bracket. We placed Butyl Tape around the screw holes (grey) and VHB Tape in the middle (red).
3. Attach Panels To Van Roof
After preparing the underside of the Z-bracket with tape, hoist the solar panels to the roof of the van and start screwing them down with the provided screws that came included with the Z-brackets.
4. Seal Around Z-Bracket Feet With Lap Sealant
Lastly, extrude lap sealant over the feet of the Z-bracket as a final water barrier.
Allow the sealant to cure for 48 hours.
Connect Solar Panels To The House Batteries
1. Connect Solar Panels In Parallel
Under most circumstances, if you have multiple panels, you will want to connect your panels in parallel.
To connect panels in parallel, you will need branch connectors to connect all the negative output lines from each of your solar panels together and all the positive output lines together.
2. From Solar Panels To Entry Gland
After adding branch connectors, you should have a single negative line and a single positive line.
Bring these two lines inside your van by using a solar entry gland. You’ll need to drill a hole in your van’s roof to attach the solar entry gland, so make sure you waterproof edges well with lap sealant.
3. From Entry Gland To Solar Charge Controller
Once inside the van, bring the solar wires towards your house batteries. You should fit a 10amp MC4 fuse on your positive solar wire to prevent unexpected electrical surges from damaging your internal electrical components.
Finally, you can connect both your red and black wires to your solar charge controller.
4. From Charge Controller To Bus Bars
From the solar charge controller, run your negative line and connect it to your negative bus bar.
Take your positive line and connect it first to a 30amp circuit breaker and then finally to your positive bus bar.
The Final Result (Fig 5.1)
When completed, the solar part of your camper van electrical system should look something like in the diagram below.
STEP 6: Connecting House Batteries To A Vehicle's Starting Battery
One of the best and most reliable ways you can charge your camper’s batteries is by driving. When you drive, the engine automatically begins to charge your vehicle’s starting battery. And with the right connection, you can also charge your house batteries while driving.
What You Need
1. Vehicle Battery To Fuse
2. Fuse To Lithium Battery Isolation Manager
Next, run another short piece of 2/0 wire from the fuse to the “Batt Chassis” post on the lithium battery isolation manager (BIM).
This isolation manager is the brain of the battery charging process and cycles the charging process on and off to prevent overheating of your vehicle’s alternator.
3. Connecting To Our Campervan Batteries
With 2/0 wire, connect the “Batt Coach” binding post of the BIM to the positive bus bar.
4. Ignition Connection & Grounding
In order for the battery monitor to know when the ignition is turned on, we hooked a 12awg wire from the BIM post labeled “Ign” to our van’s fuse box under the hood. We found an unused fuse socket that is ONLY activated when the van is turned on and stuck our 12awg into the socket.
To ground the whole system, take another 12awg wire and connected from the BIM’s “Gnd” post to a ground point on the van’s chassis.
Final Result (Fig 6.1)
When finished, the entire connection should look like the diagram below.
Finished! Complete Camper Van Electrical System
If you followed our campervan electrical installation from step 1-6, you would end up with a flexible and robust electrical system that you can rely on no matter the environment you’re in.
1. Three ways to charge your batteries
- Solar Panels
- Shore Power
- While Driving
2. Properly placed switches, fuses, & breakers
All ‘downstream’ components are protected from unexpected electrical surges with the switches, fuses, & breakers we put in.
3. Birdseye Snapshot of Your Electrical System
With the bluetooth-enabled Victron Battery Monitor and Solar Charge Control, we are able to understand the status our electrical system day after day. We always know what our battery’s state-of-charge is as well as how much solar energy we harvested that day.
Final Camper Van Electrical System Diagram
If you finished building your camper vang electrical system following our steps, your system should look similar to the diagram we put together below.
Remember, you can always download our Van Electrical Wiring Diagram for FREE.
Tips To Maintain Your Camper Van Electrical System
Just because you’ve finished building your camper van’s electrical system doesn’t mean the work is over. While traveling in your van, it’s a good idea to keep up with proper maintenance of your electrical system.
In our case, maintaining our van’s electrics mainly involves two areas.
Best Battery Charging Tecniques
Knowing how to properly charge your batteries is crucial to the long-term health and lifespan of these batteries. Spoiler alert: Different battery chemistries require different charging strategies.
Did you know:
- Traditional AGM batteries should not be discharged lower than 40%?
- Lithium batteries don’t like to be constantly kept at 100% charge?
Doing either of the above can significantly reduce the lifespans of those batteries. And we’ve seen multiple van lifers throw away almost new batteries simply because they didn’t understand proper battery charging & discharging techniques for their own batteries.
If you’re interested to learn more on how to maximize your battery’s lifespan and prevent unnecessary, additional battery expenditures, read our battery maintenance article.
Make Sure Screws & Bolts Are Tight
Because of all the vibrations that our camper van incurs due to driving, all the screws and bolts in our van electrics become loose over time.
Of course, we want everything in our van generally being held tight together, but loose electrical components is also a fire hazard. Short circuits in a camper can, and do, happen.
So once a month, it’s a good idea to take a screw driver and a ratchet and make sure every screw and bolt is fastened tightly.
FAQ - Camper Van Electrical Systems
Watts, Amps, & Volts. Do I Really Have To Understand These Electrical Terms?
Eh, not really. You definitely do not need a degree in electrical engineering to complete your own campervan electrical system. You can simply follow our free PDF guide and be one your way. But if you’re interested to learn more, knowing basic electrical jargon can help you better understand what’s going on “under the hood”.
I Have Zero Electrical Experience, Can I Do All This By Myself?
Yes, you can! We also had zero experience in electrical systems and managed to piece together quite a complicated system that has served us well for over 2 years. Our step-by-step electrical installation instructions can get you from start to finish.
There Are So Many Different Wire Sizes. Which Do I Need?
We understand there are ways to calculate the ‘proper’ wire size you need for each type of electrical device you want to run based on that specific device’s power consumption. Frankly, it’s a waste of time.
We list the only four wire sizes you need for your electrical system.
How To Ground Your Camper Van Electrical System?
Unlike a regular house, a vehicle doesn’t have normal “ground” points. In the case of campervans, it is OK to ground your electrical devices to the vehicle’s chassis. In our Ford Transit there are multiple “ground” chassis connection points.
The above diagram shows all the possible chassis ground points on a Ford Transit van. We primarily used 31 & 35 for our ground points.
MPPT Charge Controller vs Cheaper PWM?
Those converting their campervan’s on a budget tend to purchase PWN Solar Charge Controllers because of their lower price point. But the newer MPPTs are roughly 10-20% more efficient at putting solar energy back into your batteries. To us that’s enough reason to spend a bit more on an MPPT.
Should I install a tilt system for my solar panels?
Being able to tilt solar panels towards the sun can significantly boost your daily intake of solar power, which is especially useful in the winter when the sun has a lower travel arc. We did not install a tilt system and our 350 watts of solar have provided more than enough power in both winter and summer traveling. And in the small occurrences when our batteries do run low, we simply hook up to our van’s vehicle starting battery to charge our batteries while driving.
Do you recommend getting an inverter/charger so you can connect to shore power?
Having the option to connect to shore power is convenient. Though we do not often stay at pricey RV parks with supplied shore power, we do on occasion stay at these parks for 1-2 weeks to rest and recoup. Being on the road 24/7 is draining! And we’ve found that many RV sites are quite shaded, which is nice, but is terrible for harvesting solar power. In the shade, our batteries will reach 0% in 4-5 days. So being able to connect to shore power has given us more flexibility.
I’m building my camper van electrical system on a budget. What should I not skimp out on?
100% don’t try to save money on batteries. They are the life blood of your campervan electrical system. And so much of ‘van life’ depends on electricity. Even if you can’t afford fancy lithium batteries, as best as you can, get good quality AGM batteries. And while battery quality is important, battery QUANTITY is just as crucial. Read our article to figure out what size battery bank you require. Undersizing your battery bank will lead to faster battery degredation and wasting money to purchase new batteries.
Recommended Tools To Build Your Camper Van Electrical System
Final Thoughts: Building Your Own Camper Van Electrical System is Rewarding!
We hope you learned enough from our camper van electrical system article to be able to build your own electrical setup.
When we first started, the whole process was completely overwhelming. There were so many components to purchase and so many steps to complete. But we took our time and made sure each step was done to the best of our abilities.
In the end we found the entire process of building our own electrical system in our van conversion both completely doable and a highly rewarding process!
If you have any questions or comments about our van electrics article, please post a comment below or send us an email through our Contact Form.