Which wire sizes should you be using in your camper van? With over 15 different wire sizes, it can be confusing to know which sizes you need to build your van’s electric system. Choosing too thin of a wire can be a fire hazard, but selecting too thick of a wire is a waste of money.
In this post, we recommend the best wire sizes for each section of a camper van’s electric system. The wiring sections we’ll go over are:
- Battery & 12v System
- Solar 'PV' System
- Inverter System
- Charge While Driving
Best Quality Wires: All our wire recommendations are pure copper, stranded wires. We ignore the cheap copper-clad aluminum (CCA) wires and go straight for pure copper. This ensures your wires can safely handle the correct amount of electrical current.
So if you’re ready, let’s get to it!
Confused where to start with DIY electrics? Check out our comprehensive camper van electrical system guide to start from the very beginning.
Camper Van Wire Size Summary
Unsurprisingly, different sections of a van’s electric system requires different size wires. That’s because different sections of your electrical system will have different amounts of current (A) running through the wires.
Below is a summary list to help you locate the best wire size for each section.
Section | Wire Size | Where To Buy |
Combining batteries | 2/0 AWG Wire | |
Battery to bus bars | 2/0 AWG Wire | |
Battery to inverter | 2/0 AWG Wire | |
Battery to 12V panel | 2/0 AWG Wire | |
Charge while driving | 6AWG | |
Solar 'PV' System | 10AWG* | |
Inverter to sockets | 12AWG | |
12V panel to devices | 14AWG |
*10AWG will most likely be the size you need for your solar PV system. But read our solar wire size guide to double check.
Check out this handy chart for more on the official amp ratings for each wire size.
Free Ebooks To Learn More: To better understand how all these different wires come together to make a single electrical system, we recommend downloading our electrical wiring eBooks. You can download them below and they're completely free.
Download our electrical eBook to visualize which wire sizes you need.
Section 1:
Combining Batteries: 2/0 AWG
If you are connecting multiple batteries together – either in series or in parallel – 2/0 AWG is the ideal wire size to use. This wire thickness will easily handle your entire electrical load and is perfect for an inverter rated up to 3000W.
We recommended 2/0 AWG wires from EWCS because of their unmatched flexibility for their thickness. This wire is made up of hundreds of tiny copper strands, making it easy to bend the wire to connect all your components in a tight space.
The wire jackets are also water, oil, & corrosion resistant, making them ideal for use in a camper van.
- Highly flexible 30 gauge copper stranding
- Sunlight & UV resistant
- Perfect for connecting batteries, inverter/charger, & 12V fuse panel
- Pure copper wire - Made In USA
We will be using 2/0 AWG wire for other connections below, so we recommend getting at least 10-15′ of red and black wire.
These wires are also made in the USA, which we love.
Recommended 2/0 AWG Wire Accessories
Below are the components and tools we recommend to successfully wire multiple batteries together.
- Copper Lugs – These lugs help to attach the 2/0 AWG wire to the battery terminals. Heat shrink is included.
- Klein Tools Cutter – Cuts through 2/0 AWG wire.
- Hydraulic Crimper – Crimps the copper lugs onto the 2/0 AWG wire ends. Get this instead of the cheaper hammer lug crimper. WORTH IT.
- Heat Gun – Activates the heat shrink over the copper lugs and 2/0 wire.
- Utility Knife – Cuts away the protective jacket over the 2/0 wire.
Related Reading
Section 2:
Batteries To Bus Bars: 2/0 AWG
Next, you will want to connect your batteries to the bus bars (power distribution/collection centers). And along the way, you may want to include a fuse, master switch, and a battery monitor.
In this section, we still recommend 2/0 AWG to connect these components together in order to safely handle the large amounts of current that will pass through.
- Highly flexible 30 gauge copper stranding
- Sunlight & UV resistant
- Perfect for connecting batteries, inverter/charger, & 12V fuse panel
- Pure copper wire - Made In USA
Section 3:
Bus Bars To Inverter: 2/0 AWG
Of all the devices in your camper, the inverter will likely draw the most current from the batteries. And if you have an inverter/charger model, this device will be taking large amounts of current from shore power and putting them back into your batteries.
That is why we still recommend using 2/0 AWG wire here.
This wire is the perfect size for any inverter rated up to 3000W.
- Highly flexible 30 gauge copper stranding
- Sunlight & UV resistant
- Perfect for connecting batteries, inverter/charger, & 12V fuse panel
- Pure copper wire - Made In USA
Warning: A lot of cheap inverters on Amazon come included with their own wires. But these wires are often cheap copper-clad aluminum (CCA). CCA wires are rated for less current than pure copper wires and can overheat if used incorrectly. That's why we still recommend to use pure copper wires from EWCS instead.
Additional Recommended Parts
To complete the wiring process, we recommend the following parts.
- Victron Inverter – This model handles up to 2000W and can also charge the leisure batteries when connected to shore power. We use this same model.
- Copper Lugs – Connects the 2/0 wire to the inverter and to the bus bars.
Related Reading
Section 4:
Batteries To 12V Panel: 2/0 AWG
The wire size you use to connect the bus bars to the 12V panel depends entirely on the total load of your 12V system. However, to keep things simple (and because you will likely still have 2/0 wire left over), we recommend using 2/0 AWG wire to make this connection.
- Highly flexible 30 gauge copper stranding
- Sunlight & UV resistant
- Perfect for connecting batteries, inverter/charger, & 12V fuse panel
- Pure copper wire - Made In USA
Additional Recommended Parts
Below is a set of products we recommend to successfully connect the bus bars to the 12V distribution panel.
- Copper Lugs – Connects the 2/0 AWG wire to the breaker and fuse panel.
- 120A Circuit Breaker – Protects the 2/0 wire and 12V panel from over-current situations.
- 12V Fuse Panel – Distributes power from the batteries to all downstream 12V devices.
- Blade Fuses – Protects all individual 12V devices from over-current situations. Insert into 12V panel.
Related Reading
Section 5:
Charge Batteries While Driving: 6 AWG
6 AWG is the recommended wire size when building a system to charge your camper batteries while driving. This assumes you are using a proper DC-DC battery charger, like the Victron Orion. Be sure to get a spool of red and a spool of black wire.
- 25 feet of 6 gauge marine grade wire
- Tinned pure copper strands to preform in harshest marine environments
- Perfect for alternator charging connections
- Ultra-flexible wire that exceeds all UL 1426 standards
Recommended 6 AWG Wire Accessories
Below are the three additional parts you will need so that you can charge your camper’s leisure batteries from your vehicle’s alternator.
- DC-DC Charger – This device takes power from the vehicle’s starting battery and charges the leisure batteries. The device only turns on when it detects that the engine is running.
- 50A ANL Fuse – This fuse protects the 6 AWG wire from overheating during over-current situations.
- Copper Lugs – Connects the 6 AWG wire to the 50A fuse and to the bus bars.
Section 6:
Solar 'PV' System: 10 AWG
In most cases, 10 AWG wire is the ideal size to build a solar system in a camper van. This includes wiring the solar panels to the charge controller and then from the controller to the bus bars.
However, the exact size of the solar wires depends on the total size of your solar array and how the panels are connected (series vs. parallel). That’s why we recommend reading our solar wire size guide for a complete wire size breakdown so that you get the wiring size right.
- 25 feet of red 10 AWG marine grade wire
- Water, corrosion, & UV resistant, perfect for rooftop setting
- Exceeds all UL 1426 standards
- Be sure to pick up 25 additional feet of black wire
But whichever wire size you need (10 AWG or otherwise), the marine-grade Ancor wires are some of the best for solar installation.
That’s because we’ve found that their tough wire jackets do a great job at protecting the copper wires from the outside elements, like rain and UV light.
Is ‘Marine Grade Worth It?’
Our solar wires take quite a beating on our van’s roof. Though the wires that came included with our solar panels are faded (from UV exposure), our marine-grade cables still look like new. So we think these wires are worth the extra cost.
Recommended Solar Wire Accessories
Product | Purpose | Where To Buy |
Wire Cutter & Stripper | Cuts, strips, and crimps thinner electric wires. | |
MC4 Connectors | Critical connectors when building a solar system. | |
Solar Wire Entry Gland | Protects solar wires when transferred through the van's roof. | |
M6 Ring Connector | Connects solar wire to circuit breaker. | |
M10 Ring Connector | Connects solar wire to bus bars. | |
Solar Charge Controller | Controls solar charging process to the batteries. | |
40A Circuit Breaker | Protects wires and solar system from surges. |
Related Reading
Section 7:
Inverter To Sockets & Shore Power: 12 AWG
12AWG is the ideal size when connecting the inverter to power sockets and to shore power (if you have an inverter/charger model).
Make sure you purchase wire that is marked as “12/3 AWG”. This means that there are three individual 12-gauge wires encompassed in a single outer wire jacket. This is useful for keeping the wires neat as well as adding an additional layer of wire protection.
- Ultra-flexible standing resists fatigue from vibration
- Tinned pure copper wire to preform in harshest marine environments
- Includes positive, negative, and ground wire
- Exceeds all UL 1426 standards
We purchased these 12/3 AWG wires and they’ve worked great for us, no matter what 120v electrical device we’ve used. This is also a very flexible wire, which can come in handy in a cramped camper van.
Recommended 12 AWG Wire Accessories
Product | Purpose | Where To Buy |
Circuit Breaker Box | Holds the 15A circuit breaker. | |
15A Circuit Breaker | Protects downstream wires and electrical devices. | |
Power Outlet | Standard 120V socket. | |
Wall Plate | Socket frame. | |
Gang Box | Attaches to socket behind the wall. | |
Wire Splitter | Splits 12 AWG wire into multiple paths. |
Related Reading
Section 7:
Wiring 12V Devices: 14 AWG
14AWG wire is perfect for wiring all the 12v devices in a camper van to the 12v distribution panel. This includes wiring the vent fan, water pump, led lights, and standard 12v sockets.
When shopping for 14 AWG wires, look for “14/2 AWG”. This means that two 14-gauge wires are packed inside an additional outer jacket, like this one from GS Power.
- Durable insulation jacket for protection against heat, water, and UV light
- Perfect for wiring all 12V devices
- Stranded & flexible for protection against driving vibration
- Marine grade for best quaity
Because of the constant vibration camper van’s experience while driving, protecting the wires with an additional outer jacket is a smart move to prevent short circuits and potential fires.
Recommended 14 AWG Wire Accessories
Below are the components you will need to wire the 12V fuse panel to many of the 12V devices in your camper.
- 12V Fuse Panel – Distributes power from the batteries to all downstream 12V devices.
- #8 Ring Connectors – Connects the 14 AWG wires to the 12V panel.
- Butt Connectors – Connects the 14 AWG wire to each 12V device.
- Light Switch & USB – Popular RV-style switch for LED lights. Includes USB C & A sockets.
- LED Puck Light – Popular LED puck light. Energy efficient, bright light, and slim profile.
Related Reading
Download our electrical eBook (with diagrams) to visualize which wire sizes you need.
Campervan Wiring Tips
1. Decide A Wire Origination Point
Before laying out all your electrical wires, decide where in the camper you will build the center of your electrical system. This will be the location of your batteries, 12v distribution panel, inverter, and all other electrical components. All electrical wires should originate from this region of the camper.
The center of our electric system is located above the passenger-side wheel well. You can see how we had all our electric wires originate from this location.
2. Use Split Wire Loom To Protect Your Wires
Regretfully, we did not do this. But putting your electric wires in a split wire loom [Amazon] plays a critical role in protecting the wires.
- Size: Inner diameter-Length: 1/4"-10ft 3/8"-10ft 1/2"-10ft|Color: Black. Our wire loom is made of...
- Our split loom is split and easy to put wires in. Our split loom tubing is thick enough to provide...
- Operating temp (degree F.):-94 to 257 | our split wire loom is used to protect electrical wiring in...
This is important in a camper van because you’ll be creating lots of vibration throughout the vehicle while driving. And if your unprotected wires happen to be resting next to another object, constant vibration can work to cut through the wire’s outer jacket and expose the bare copper wires inside.
This is a fire hazard.
You can also hold these wire looms in place along the van’s metal frame with these 3M adhesive mounts [Amazon].
How To Ground A Camper Electrical System
For safety, you should ground your camper’s electric system. But instead of connecting to an actual ‘ground’ point, you simply connect to a designated spot on your vehicle’s chassis.
For information on your specific vehicle’s chassis ground points it’s best to search for these points either in your vehicle’s handbook or by searching on the Internet.
If you have a Ford Transit, like we do, we’re posting an image of all the chassis ground points below. In our electric build, we grounded our system by connecting to point #31 in the below image. Download our electrical wiring eBook to learn how to ground your camper’s electrical system.
Speed Up Your Electrical Install Process With Our Free Diagrams
Did You Find This Van Life Tip Helpful? We have lots of other useful articles to help you travel better in your camper van or RV. Check out our Electrical System Guide to read more great van life content!
Final Thoughts: Campervan Wiring Is Just The Beginning!
Thank you for making it this far in our campervan wiring post! We hope you learned a thing, or two, about best wire size and placement in your own van conversion.
But buying the right wires and laying them in your van is just the first step. This blog has so many more posts to get your campervan electrics up and running. Check out these posts below for more information.
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