Campervan Wiring

The first task for today was to remove the Styleline panels and roof lining from my T4 Camper. It took me around an hour to remove this and another half hour to remove the roof lining and trim from the front of the van.

I had originally planned to install my two 75Ah Optima Gel batteries separately under the drivers and passenger seat boxes. I have now decided to install them at the back of the VW T4 underneath the bed because I'm going to install my PC system under the drivers seat and possibly an amplifier or safe under the drivers seat. The other reason is so the batteries can be sat very close to each other as this is advantagous as they need to be wired in parralel to make them appear as one larger battery.

The main disadvantage of having the batteries at the back is that I will now need to run a hefty charging cable from the alternator to the batteries at the back of the T4. There are 2 possible ways of doing this, I can run the cable underneath the campervan and then up through one of the back lights. Alternatively I can run the cable up the windscreen pillar and then along the roof and down the rear piller and out through the light. I chose the latter method as even though I'll need a longer cable run I'd rather not have wires dangling down underneath the van.

Before starting the wiring it is best to make a list of all the electrical appliances including power consumption you intend to run in your campervan. You should also try and decide there location and estimate how much wire you'll need from the appliance to the power source which is normally the leisure battery fuse box. You can then decide how thick a wire you'll need to keep the voltage drop to a minimum, I decided on 3% as the maximum voltage drop some people decide that 5% is acceptable. You may also wish to consider using a ring of cable (both ends joined to the power source) as this will halve the voltage drop. I chose a ring for my lighting and also for the accesory sockets as I intend to have a few of these.

I decided to run all the wiring through the roof and down through pillars when required. It will all be run through PVC sleeving to protect it from chafing a shorting, the thicker wire such as the 25mm cable for the split charge will be run through convoluted tubing. It will all eventually exit the roof through the rear pillars and out through the rear lights.

It turned out to be quite a slow process as its difficult to pass long lengths of wire through the PVC tubing and I spent around 2 days threading the wiring and soldering the required spurs for appliances. I then used foam matting and carpet adhesive to secure any wires that were dangling down.