Ahh the dreaded camper van electrical system 🙃 If you’re like us, you may be intimidated by this step in the van build. There’s definitely a learning curve, but fear not. We’re here to help! This post will explain the role of each component in our electrical system, and how we installed them.
We’ll be linking the exact products we used, but your system may vary based on your needs! For example, some camper vans have 100 watts of solar, and some have 600+ watts. We rolled with 300 watts. For reference, we typically land somewhere in the middle of bare minimum and excessive.
This post is pretty lengthy, so feel free to jump to what you’re looking for:
Electrical Components Explained
What You’ll Need
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Main Components
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Inverter (or this inverter is another great option and costs less)
Installation Tools & Materials
Stranded Copper Wire – sizing will vary based on application. For a more detailed explanation on wire sizing, check out our prewiring post.
Screwdriver
Electrical Components Explained
Solar Panels
We have three 100W Renogy solar panels mounted to the roof of our van. These panels convert the incoming solar power to electrical power and bring in an average of 0.8-1.2KWH each daily (weather depending of course!). The energy collected from the panels then moves on to the solar charge controller.
Solar Charge Controller
Our Solar Charge Controller is connected between our solar panels and our house batteries. It controls the rate at which the batteries are charged by the solar panels, which allows for optimal charging voltage for the batteries at all times and prevents both overcharging and battery drainage.
Bluetooth Module
The Bluetooth Module plugs directly into the Solar Charge Controller so it can “talk” to our monitoring system and phones.
DC-DC Charger
Our DC-DC Charger allows us to charge our house batteries from our van battery. This works by tapping into the starter battery and transferring the additional charge created by the van’s alternator into our house batteries. It’s perfect for generating power while we drive.
Inverter
We have the Renogy 3000w Sine-Wave Inverter. It takes power from the house batteries and converts it to AC power, which is sent through our 120v electrical outlets, and powers any device that’s plugged in. Typically with inverters there’s a loss of power in the conversion from DC to AC. With a Sine-Wave Inverter specifically, this loss is not as significant, and the process is quieter, smoother and more reliable. It also has an additional input for connecting and charging via shore power if we need an extra boost.
House Batteries
To clarify, we use the term “house batteries” to differentiate from the van battery that starts the engine. We have two Renogy 200ah Lithium-Iron Phosphate Batteries that together can store 400ah of power. These can be safely discharged to 0%, have built-in Bluetooth connectivity, and contain a very advanced battery monitoring system.
We chose lithium iron phosphate batteries (LiFePO4) because they outperform standard lead-acid or absorbed glass mat (AGM) batteries in a few ways. They’re safer, weigh less, have a longer life span, and require zero maintenance. They also have a high depth of discharge (DoD), so more energy can be drained from the battery without causing damage or shortening the lifespan.
12V Fuse Panel
The fuse panel acts as the central switchboard for the electrical system. It receives power and distributes it to various circuits.
Fuses
These are safety devices that prevent systems from exceeding amperage limits. If too much current is flowing through a fuse, it creates a gap in the circuit, protecting the more expensive components from damage.
Kill Switches
These are optional, but we chose to install emergency shut-off/simple disconnect switches for incoming power systems.
Renogy ONE
Once all these components are installed, it can be arduous to keep tabs on all of them. The Renogy ONE allows us to monitor the entire system through one screen. It wirelessly connects to all our Renogy devices and provides information about power consumption, incoming power, and battery status. We have a whole post about this bad boy. Check it out here.
One More Thing
We also have a Renogy Phoenix 200 Portable Power Station. It’s a great addition to our power system. It can charge six devices at once, which gives us the boost we need on days when the sun isn’t shining on our solar panels. It’s lightweight and compact, which is perfect for our small space.
Our Electrical Diagram
If you take one thing away from this blog post, let it be this diagram!
Installation
Solar Panels
Before installing the solar panels, we secured the three of them together for extra stability. We did this using the preexisting mounting holes on the underside of the panels, with metal plates, bolts, and screws.
Following the included diagram, we made all the appropriate cable connections on the backside, combining the flow of power from three separate panels into singular positive and negative power cables.
Then we used the included mounting brackets and self-tapping metal screws to secure the panels to the roof of the van. Between the roof and the brackets, we added a layer of butyl tape as our second line of defense against leaks. The first line of defense is self-leveling lap sealant over the screws and bracket edges.
We drilled one ½” hole in the roof of our van for the cables to run inside. These cables were run through the supplied cable housing and into the van. We used butyl tape and sealant on this component as well.
Before moving on the next component, we double checked our work by touching the positive and negative ends of the solar panel cables to a voltage tester. It showed power coming in, which told us the cables were connected correctly.
Solar Charge Controller
We stripped and inserted the incoming wires from our solar panels into the corresponding inputs (positive and negative) on the charge controller and used a screwdriver to tighten the connection, essentially pinching and securing the exposed wires to the device. The positive wire of the incoming solar power was run through a 40 amp fuse as a safety precaution, and the negative was grounded to the chassis of the van. The outgoing wires take the converted power straight to the house batteries, but the positive wire was run through a kill switch that allows us to cut our solar input off completely. The charge controller came with a mounting plate built-in, so all that was left was to screw it into place.
Bluetooth Module
The easiest installation of all! This simply plugs into the solar charge controller and comes with two screws for mounting to the wall.
DC-DC Charger
The DC-DC Charger was a little trickier to install and it is actually mounted away from the rest of the system, under the driver’s seat. It has connections from the van’s battery to the charger, and from the charger to the house batteries. We then ran a small gauge wire and spliced it into the D+ signal wire of the van. This wire provides a current to 12V systems specifically when the van is running, so that the DC-DC Charger does not pull from the van’s battery while it’s off and accidentally drain it.
Inverter
We started by mounting the inverter to the floor of our van, since this beast weighs around 70 pounds and we do not want it loose in-transit. Next we stripped the 12/3 Romex wires that are connected to our power outlets, and attached them to the inverters connections, using a screwdriver to clamp the wire into the connection securely. We followed that same process to connect the positive and negative battery terminals. Positive to positive, negative to negative, and ground to ground. In this case, we secured the ground cable to an unpainted part of the van chassis.
House Batteries
We wanted to keep our electrical system condensed to one corner of the van, so we built a stand that allows us to stack the batteries on top of our inverter and wheel well. They weigh 60 lbs. each so we made it nice and sturdy!
The batteries are connected to a lot of other components, so I think a visual explanation is easiest here! Check out our electrical diagram.
Connecting batteries and other electrical systems can be dangerous work, but following electrical safety rules will keep accidents from happening. A good rule to follow is to connect positive first, then negative. For disconnecting, it will be the opposite: negative first, then positive. Be warned, you may see a spark when connecting the negative. That’s fine, it’s just the circuit closing!
Fuse, Fuse Panel, Kill Switches, Breaker Box
Now that all the main components are installed, it’s time to connect them all.
For our 12v system fuse box, wiring was very straight forward. After splitting the wires into positive and negative and crimping on ring terminals, the terminals were then screwed into the panel on their respective sides. The screw sandwiches the terminal ring to keep the connection secure. Larger connections in our system, such as the wires joining batteries and from the batteries to the inverter, used wire lugs.
The top and bottom screws in the center of the panel are positive and negative terminals used to connect the panel itself to our batteries directly. Fuses were then put in the slots on the main board. These are safety devices that prevent too much current from being passed through. We found these cable clamps to be very helpful in wire management!
Here’s what our camper van electrical system looked like when we were all said and done.
I know this step in the van build can be confusing, so please feel free to reach out with questions! You can do so through my contact page or shoot me a DM on Instagram.