Week 52 - Electrics 1

It is now a whole year since I started work on the van and I can finally see light at the end of the tunnel. I have finished my electrical scematic (see below) and I was confident enough to make a start on tackling the bulk of the electrics this week. The diagram shows how the system will work: The batteries are charged from a battery charger when main electricity is available, and by the engine when it is running. The 12v equipment is run straight from the batteries through a fusebox and the 230v stuff can be switched between a consumer unit or an inverter depending on whether mains electricity is available. Simple, right?

I had a couple of days free from my day job so I managed to progress quite far with fitting all the electric gear. It looks a bit messy in such a confined space but I think everything so far is set up well and pretty secure.

The cable from the leisure batteries has been connected to a 100A relay which will supply power from the alternator. This is then attached to the batteries via another 80A midi fuse. The relay is triggered by a 30A smartcom unit which detects the current from the vehicle battery and only allows the relay to charge the leisure batteries when the vehicle battery is fully topped up.

The power coming from the leisure batteries goes to an isolator switch which will then go to the fuse box. This allows me to turn all the power on and off in one go. Another isolator switch is fitted to the 400W inverter unit. The inverter produces a mains voltage from the 12v it receives from the leisure batteries. As a result though, it is very inefficient and will drain the batteries quickly (it produces 400w no matter what, if anything, is plugged in). This switch allows me to turn the inverter on and off as required.

As well as the isolator switches, I wanted to be able to check the condition of the leisure batteries without lifting the front passenger seats. I therefore cut a section out of the frame and fitted a display gauge in place with caphead bolts.

In retrospect, I would have bought a more accurate digital display rather than a simple green-to-red scale.

Week 51 - Battery Charger

This week I could return to the electrics. I had previously invested in a CTEK M200 battery charger (about £120) which I could now install in the van. It is a waterproof charger made for use on boats but it fits the specification of my system and will fully charge my two batteries in a few hours. CTEK are renowned for making quite reliable chargers for this kind of purpose too.

I fitted the charger on the shelf and screwed it down in place. The shelf above it will need to allow for the charger leads to connect through to the leisure batteries and the plug to connect to a socket from the consumer unit.

While the charger will keep the batteries topped up when connected up to the mains, they will also need to be charged from the van alternator while the engine is running.

For this, I need to run a thick (16mm) cable from the main vehicle battery positive terminal, under the van, to the leisure batteries (via a smartcom unit and a big relay). I made up some cables, and after removing the old relay from under the bonnet, I fitted an 80A midi fuse in a fusebox in its place. Another cable from here goes underneath the van and up underneath the leisure batteries where the electrics are housed.

Week 50 - Bike Rack

I ordered a bike rack (£39 including postage, eBay) to fit to the van. After a bit of research, I decided on a rack to carry 2 bikes which would fit to the van tow bar – more secure than those which hook over a car boot door.

By fitting to the tow bar, I figured there is much less chance of the rack not fitting to the van. The rack is surprisingly easy to fit and it’s really secure when connected on the tow bar.

Two further straps fit to the van doors and the arms can be positioned to grip the bikes in little holders with grooves and rubber ties. The only thing I would say is that the distance between these arms cannot be adjusted so it will not fit bikes with smaller frames very well - perfect for my needs though.

I do however need to get an extra number plate now as the original is covered up when the bikes are on.

Also, this week I added a 23 litre waste water tank which sits perfectly under the rear right-hand-side corner of the van where the waste water pipe comes. This tank fits snugly behind the double rear seats when not in use.

Week 49 - Re-Wiring 2

While re-wiring the back of the van, I decided to do the same to the water pump and tap. I had been advised that connecting the microswitch in the tap directly to the water pump could blow the switch as it is not designed to take a very big load. The solution? To fit a 30A relay triggered by the microswitch which will then isolate it from the current running to the water pump. The downside of this was that I needed to fit a 2-way fusebox and a relay under the sink.

 After wiring everything up using the same methods of crimp terminals and electrical tape, I fixed the relay and fusebox (5A to the microswitch, 20A to the water pump) to the inside of the cupboard. The test worked perfectly so the electrics can now be boxed in without fear of blowing the switch.

I used wooden batons and a piece of ply to box the electrics in the corner without taking up too much storage space and the job’s a good ’un.

I do wish I had more of an idea of the electrics earlier in the build though as it would make this stage much easier if planned more beforehand.