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This is not advice, merely a reference to myself. Do not use this as a guide.

Initial Wiring Diagram

Analog wiring diagram here. Missing wire sizes, colours, and doesn't include all parts of system. TODO add 12V main wiring, LV cutoff circuitry, digitise. Need inline fuse on the LV cutoff too, also on the fairy lights. Need to work out solution to plug in socket externally so that we don't have issues with trickle charge. Correct 17mm cable to 17A cable on fuse box.

Digitised Wiring Diagram

I'm currently trying to digitise this diagram using qelectrotech, mainly as an exercise to myself. The project file is here, with the latest schematics here.

Current Wiring

Fusebox in the kitchen cupboard at the back. This fusebox has some tails which connect out to various circuits. In addition to the fusebox, there is the split charge relay, which is connected out to the front of the van and is on a voltage sensing relay. There are two isolator switches. The first isolates the leisure battery from the circuit, the other isolates the split charge aspect of the system.

To de-energise the system, both have to be disconnected.

The fusebox connects to the aux power on the side of the kitchen cupboard, the diesel heater, the lights, and the aux power at the back. It also connects through to the inverter. The inverter is a 250/500W peak, so would have current spikes of 41A at 12V. The spec sheet didn't say the sizing of the cable required. The calculator here said a CSA of 8.37mm2 would be needed.

Currently this is a paralleled twin and earth just using the L/N of the wire. This needs replacing with flexi cable. Also not earthed.

Inverter has a single plug atm, want to wire it up to have multiple plugs in the van. Need to replace solid core twin and earth runs with flexi. Lights on twin and earth and also on a twin switch circuit with no conduit so cannot easily be replaced. Run from the cupboard to back aux also currently on mains twin and earth, so need a 12V DC to the back, then

Mains Wiring

Inverter can do 500W peak at 230V, or 2.17A. Mains cable needs to be able to handle this AWG25 or 26 ideally 0.16mm2 CSA. Can put one at the back of the van next to current aux power, one next to the aux power up front, then maybe a small spur that goes to a free floating plug in the front for running wiring outside the van. Could also just wire a plug next to a socket on the underside of the van. This would then allow the mains to passthrough the van?

Shopping List

Nice to have

  • 18AWG or better red and black sheathed ideally to run into the back, approx 5m? Cig lighter can draw 16A and current tails for 18AWG
  • Lugs to crimp with
  • Crimping tool
  • Label Maker
  • Fish wire
  • Pull cord
  • More conduit
  • Gland for mains flexi? Maybe not bother
  • 12V light for cupboard to come on with main lights, maybe wire it so it is a switched spur on the main lighting
  • small 12v switch
  • Trickle charger
  • 16A plug and socket for external mounting
  • 12V 100A relay with lowish hold current
  • Transfer switch
  • Bus bar for earth

For Initial Mains

  • 10mm^2 red flexi 0.5m
  • 10mm^2 black flexi 0.5m
  • Mains flexi and 13A plug (ideally orange outdoor stuff, or can cut some off extension cable)
  • 2x inline fuse holders