Installing a DC/DC charger (also known as a battery to battery charger) is a great addition to any vans electrical setup. This allows you to charge you’re leisure batteries from the car battery when you are driving. We think that think installing a DC/DC charger is a no-brainer for anyone hoping to spend time off-grid – especially if the sun isn’t shining!
Although the DC/DC charger connects the car battery to the your leisure batteries it will not drain your car battery! All of your current-hungry goods in your van such as a hob, water heater or fridge will run off the power supplied by the leisure batteries. The car battery will simply top up its charge when driving.
Step 1 – Choose your DC/DC Charger
There are lots of different DC/DC chargers on the market to choose from. We opted for the Victron Orion-Tr Smart DC-DC Charger Non-Isolated
We felt that it was the best value for money. One of the main reasons we picked it was that we loved how it (along with a lot of Victron’s other products) had Bluetooth capabilities. This means you can easily check on the status of charging through an app on your phone. This gets rid of the need for unsightly monitors dotted all over your van.
Wiring the leisure batteries in parallel means double the current – 2 x 150Ahr batteries in parallel equates to 300Ahr capacity.
Our vans battery, like almost every vehicle, has a voltage of 12V DC. We have wired our 2x 12V leisure batteries in parallel, giving an overall circuit voltage of 12V (would be 24V if wired in series)./ This means the 12/12 30A non-isolated charger works perfectly for our electrical set up. The charger connects the 12V car battery to the 12V leisure batteries circuit with an output of 30A. If you are using a non-isolated charger it is very important you have a good ground point in you van to connect both batteries to. We used a large bolt going through the metal bodywork as our ground point.
Step 2 – Access The Vans Battery
If you are converting either a Citroen Relay, Fiat Ducato, or Peugeot boxer; you can access the battery via a hatch on the floor at the passenger side of the cab. Simply undo the fastenings and lift the hatch off. Your battery should look something like this:
For other models of vans, your manual should show you how to access the battery.
Step 3 – CREATE A PASSAGE THROUGH THE BULKHEAD TO ALLOW WIRES TO BE PASSED THROUGH
If you do not have a bulkhead in your van skip this step. This step is super easy. Simply drill 2 holes in the bulkhead near the bottom, large enough to feed your wires through (we used 10mm single core wire). When choosing the position to drill make sure to take into account the difference in height between the floor in the back of the van and the cab – we found that there was a difference of 4″- 6″. When drilling, don’t be surprised if the drill acts a bit strange going through the carpet lined side. You can poke the carpet out of the way when you feed the wires through.
Step 4 – Feed wires Through cab/bulkhead
Firstly, prior to feeding the wires through the bulkhead, add cable lugs onto one end of the positive and negative wires. This end of the wire will remain in the cab and eventually be connected to the vans battery. By attaching cable lugs it makes it easier and safer to connect wires to the battery. Simply strip the end of the wire, place it into the lug, and crimp it. We used a spring-loaded crimping tool which you hammer.
Feed the ends of the wires without the lugs under the plastic flooring in the cab, this will make the wires as discreet as possible. Once you have fed the wires to the back of the cab, begin to feed them through the holes you have drilled. The images below shows where you can feed the wires to keep them hidden.
Leave enough of the cable to connect to the vans battery, however, the less excess the better.
Step 5 – Connect The Wires to DC/DC Charger
Make sure to take the negative wires from both the van battery and the leisure batteries and secure them to a good ground point. If you are unsure whether or not you have a good ground point we would recommend reading this article. We found it very useful!
The wiring part of installing a DC/DC Charger is really easy. Simply strip the end of each wire and push into the correct port of the charger. Once the wires are pushed all the way in, tighten the screws on the charger to secure them firmly in place.
The diagram below shows you exactly where each wires should go when wiring up the DC/DC charger. We used 10mm single core wire throughout the circuit.
Add some circuit breakers to your circuit. We used two 60A circuit breakers to protect the batteries against a surge in current. A circuit breaker is an automatic switch that protects the circuit from an overload of current. As soon as the current exceeds the limit, the switch trips the circuit interrupting the flow of current. Unlike a fuse, the benefit of using a circuit breaker is that it can be easily reset.
Step 6 – Connect Wires To Van Battery
Below is a general diagram on how to connect the wires to the vans battery. Be very careful when doing anything with the vans battery as you don’t want to mess with how it works. Make sure to screw the lugs on tight. We found that when the connection wasn’t tight enough it messed with our wipers.
Make sure to connect the positive and negative wires to the correct side of the battery. Using red and black wires makes this easy. Another thing to note is that the vans alternator plays a major role in the operation of the DC/DC charger. This is what charges the vans battery – and everything else for that matter. We have not included the alternator in the wiring diagram as your vans battery is already wired up to it.
Installing a DC/DC charger makes a great addition to any camper van. The more ways of generating power in a van the better – especially if you intend on spending time off-grid. The installation is really easy and shouldn’t cause you too much bother
Feel free to ask us questions regarding installing the DC/DC charger, whether it is about materials, price, time, or whatever else. You can always find us in the comments.
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