Wiring a Consumer Unit and Plug Sockets

Materials/Spend

TOTAL: £107.68


After the immense amount of time I spent researching and learning about 12V electrics (and still learning), when it came around to looking into 230V electrics I was nervous that I’d essentially have to learn everything from scratch.

Fortunately, the idea is more or less the same, except you have a separate earth cable instead of just making sure everything is grounded via the negative cable.

From my consumer unit, I wanted to wire three double-plug sockets. One just next to the bed, one in my overhead cupboard and then one near my kitchen. I particularly want one in my overhead cupboard as I’m thinking of having a wall mounted monitor next to it and it also means I can charge my devices discreetly.

Laying the cable

I read a few contrasting things online, but the general rule is that you should try to avoid running lengths of DC and AC cable alongside each other. If you do, there should be something in between them or they should be at least 50mm apart. It’s generally ok if they need to intersect at any point though. Because I have my 12V lighting cable positioned around the ceiling, I needed to be strategic as to where I positioned the cable.

From the back of the inverter, I fed the cable up the back of the plywood that’s housing my water pump and up into one of my overhead cupboards where I will house the consumer unit.

From there, I fed the cable across the roof and down to the head of the bed where the first plug socket will be situated. I then fed the cable down and under my bench and then up into the opposite overhead cupboard where the second plug socket will be positioned. Finally, the cable will feed all the way along the back of my cupboards and ends up against my bulkhead just above my kitchen counter.

Fortunately, the 10metre cable that I bought was exactly the right amount!

I’m connecting my plug sockets in a radial circuit which means the cable will just feed from one plug socket to the other and end at the furthest plug socket, as seen in the image below.

A simple wiring diagram showing how I wired my plug sockets

Wiring mains plug

Once my cable was in position, I needed to connect one end to my inverter. My Victron inverter has one AC output in the form of a standard household plug, so I just used a 13A mains plug.

Once screwed open, you simply screw down the live, neutral and earth cables into their positions and then screw the plug back together. I then plugged this into the back of my inverter.

Wiring the consumer unit

A close up of how I wired my RCBO

Typically, most people will use a combination of RCDs and MCBs in their consumer units. RCD’s monitor the flow of current and will trip if there is an imbalance, where MCBs act like your standard circuit breaker.

As I’ll only have one output, I decided to use an RCBO. These are slightly more expensive but are essentially an RCD and MCB combined - much more simple! Conveniently I found a seller on eBay that sold a single RCBO in its own consumer unit that also came with a separate earthing cable.

With conflicting information online, I decided to make a unique earthing point in the van’s chassis, rather than share the existing one for the 12V system. I drilled a small hole and sanded the paintwork down to bare metal to make a good connection. The consumer unit also came with a bolt that I could use to attach the earth cable to the chassis.

The RCBO accepts incoming wires in the top and outgoing wires in the bottom, so it made sense for me to turn it upside down as my incoming wires were coming from below and outgoing were feeding across the roof of the van.

Once that was done, I fed the earth cable up into my overhead cabinet where the consumer unit will be housed. I then attached the earth cable to the little bus bar inside the unit.

I then cut the twin and earth cable that was already in position, stripped both ends and connected the live and neutral wires coming from the inverter into the input end of the RCBO and then connected the earth cable to the bus bar.

For the other end of the cable going to the plug sockets, I connected the live and neutral wires to the output end of the RCBO and the earth wire to the bus bar again.

Wiring plug sockets

Next to the head of the bed where the first plug socket will be situated, I spliced the cable again and connected both ends to the same inputs on the first plug socket.

The plug socket has colour-coded terminals for each wire and then you can screw down both input and output cables into the same terminals, so two live cables in one terminal, two neutral cables in another terminal and then finally the two earth cables in the last terminal.

I then repeated this process in my overhead cupboard where the second plug socket will be positioned.

For the last plug socket, as this is the end of the chain, I only needed to feed one of each wire into the terminals.

For the plug’s back boxes, I had ordered some slightly slimmer ones at 25mm depth that should fit nice and snug against my cladding.

If you have any questions at all, feel free to ping me an email or drop me a message on Instagram!