Will This Work?

[Greenmantle]

Not got an EV as yet but looking at installing a charger in preparation of getting one in the next 12 months.

Had a quick look at the electrics in the house (2000 build)

(1) 100A fuse
(2) no loop to neighbour
(3) There will be a problem getting a new armoured cable to the consumer unit.

Therefore will this work?
I have armoured cable from a 20A RCD (can be upgraded to 32 or 40A) to the garage. This supplies a couple of double sockets. Could I install the EV charger on the garage wall and use this supply?

Ideally I would like to keep the double sockets and I would never use the EV charger and double sockets at the same time.

[CheesecakeRunner]

Does the existing armoured cable go into a consumer unit in the garage, or straight into the double socket?

Mostly it’ll depend on the specification of the existing armoured cable. But if it’s suitable, there should be no reason why you couldn’t put a consumer unit in the garage,with appropriate protection at the house consumer unit for it, and that then feeds an EVSE and garage sockets.

But I’m no sparky.

[No ideas for a name]

Greenmantle said:

Not got an EV as yet but looking at installing a charger in preparation of getting one in the next 12 months.

Had a quick look at the electrics in the house (2000 build)

(1) 100A fuse
(2) no loop to neighbour
(3) There will be a problem getting a new armoured cable to the consumer unit.

Therefore will this work?
I have armoured cable from a 20A RCD (can be upgraded to 32 or 40A) to the garage. This supplies a couple of double sockets. Could I install the EV charger on the garage wall and use this supply?

Ideally I would like to keep the double sockets and I would never use the EV charger and double sockets at the same time.

I would change the 20A RCD supplying the garage to a 40A MCB (NOTE: Assuming your SWA is good for 40+) therefore making this effectively a sub-main.
Then a separate CU in the garage with appropriate protection. I would go with RCBOs for the sockets and the lighting, and similar for the EVSE depending on what is actually already provided inside the EVSE.
I am reluctant to trust the alledged protection devices that guard against broken neutrals. You would need to look at the earthing. Cue argument, but I think a shed or outbuilding should have an earth rod rather than an exported PME.

PS A much better plan than cramming things in the meter box (cue another argument).

IANAE

[moonigan]

Greenmantle said:

Not got an EV as yet but looking at installing a charger in preparation of getting one in the next 12 months.

Had a quick look at the electrics in the house (2000 build)

(1) 100A fuse
(2) no loop to neighbour
(3) There will be a problem getting a new armoured cable to the consumer unit.

Therefore will this work?
I have armoured cable from a 20A RCD (can be upgraded to 32 or 40A) to the garage. This supplies a couple of double sockets. Could I install the EV charger on the garage wall and use this supply?

Ideally I would like to keep the double sockets and I would never use the EV charger and double sockets at the same time.

Is the armoured cable 6mm or 10mm ? I've just had and engineer round from e-verve and he said I would need 10mm cable if I wanted another CU in my garage to feed the charger and provide seperate lighting and socket circuits.

Edited by moonigan on Tuesday 19th April 17:06

[No ideas for a name]

moonigan said:

Is the armoured cable 6mm or 10mm ? I've just had and engineer round from e-verve and he said I would need 10mm cable if I wanted another CU in my garage to feed the charger and provide seperate lighting and socket circuits.

Edited by moonigan on Tuesday 19th April 17:06

The OP did specifically say he didn't want to run both loads at the same time... a bit of diveristy or usage factor.
For supplying full load of 32A for the EVSE, 32A ring for sockets plus 6A lighting (70A) you would be looking at 10mm^2
It also depends on cable length and calculating voltage drops.

[CharlesElliott]

You need to know the length and the conductor size of the armoured cable to calculate whether it is big enough. For a reasonable run, you would need at least 6mm. For a 30m cable length, you would need 10mm @ 32A. For 40A you would need10mm around 25m cable length.

[Greenmantle]

thanks for all your replies.
The armoured cable is 10mm and the length is probably just over 12m. Therefore I think the 40A RCD with a sub main consumer unit in the garage is the way to go. My current choice for charger is zappi but obviously will listen to other choices since i’m totally new to all this.

[Heres Johnny]

A few years ago the practice of a well known EV maker was to install commando sockets in the garage, you then plugged your mobile charger into this. Over time people bought their own wall charge point and used a fly lead to the socket, but others introduced an A-B switch so they could choose how to use the supply. If the cable can be made up to regs for the charger (there are other considerations like earthing), you could potentially do something similar. Position A feeds the charger and position B feeds sockets etc. I presume such an arrangement meets regs as many did it, but I’d ask someone better qualified than me to be sure.