Home charger location

Author
Discussion

Sheepshanks

Original Poster:

32,880 posts

120 months

Friday 3rd December 2021
quotequote all
Having some work done on the house early next year and thought it would be a good idea to lay a cable from meter to garage (opposite sides of house) for a charger, thinking it could go on the wall next to the garage door (basically the garage door pillar, a brick width).

However I’m reading a lot of very complicated rules one of which seems to be that the charger can’t be within 2.4 metres of metalwork – “sim contact”, which I guess means simultaneous contact.

As the garage door is metal does this mean the charger can’t go there?

LordFlathead

9,641 posts

259 months

Friday 3rd December 2021
quotequote all
Only a qualified electrician can pick the best place for the charger. I'd wait until you've bought it then ask the question then.

Dave Hedgehog

14,584 posts

205 months

Friday 3rd December 2021
quotequote all
Sheepshanks said:
However I’m reading a lot of very complicated rules one of which seems to be that the charger can’t be within 2.4 metres of metalwork – “sim contact”, which I guess means simultaneous contact.
mines bolted to a metal post so i suspect thats bks


Dave Hedgehog

14,584 posts

205 months

Friday 3rd December 2021
quotequote all
tesla are selling off their dumb chargers pretty cheap atm

https://shop.tesla.com/en_gb/product/gen-2-wall-co...

48k

13,189 posts

149 months

Friday 3rd December 2021
quotequote all
Sheepshanks said:
Having some work done on the house early next year and thought it would be a good idea to lay a cable from meter to garage (opposite sides of house) for a charger, thinking it could go on the wall next to the garage door (basically the garage door pillar, a brick width).

However I’m reading a lot of very complicated rules one of which seems to be that the charger can’t be within 2.4 metres of metalwork – “sim contact”, which I guess means simultaneous contact.

As the garage door is metal does this mean the charger can’t go there?
That sounds like a load of bobbins, or else there must be thousands of non-compliant installs in the country, including mine (installed last month).



Edited by 48k on Friday 3rd December 13:25

Sheepshanks

Original Poster:

32,880 posts

120 months

Friday 3rd December 2021
quotequote all
Dave Hedgehog said:
Sheepshanks said:
However I’m reading a lot of very complicated rules one of which seems to be that the charger can’t be within 2.4 metres of metalwork – “sim contact”, which I guess means simultaneous contact.
mines bolted to a metal post so i suspect thats bks
I think that would be OK as it's not attached to the house.

It seems to be about having the charger (and therefore car) earthed to one place and metalwork attached to the house earthed to somewhere else.

There were a bunch of new rules last year: https://electrical.theiet.org/wiring-matters/years...

TheDeuce

21,906 posts

67 months

Friday 3rd December 2021
quotequote all
Sheepshanks said:
I think that would be OK as it's not attached to the house.

It seems to be about having the charger (and therefore car) earthed to one place and metalwork attached to the house earthed to somewhere else.

There were a bunch of new rules last year: https://electrical.theiet.org/wiring-matters/years...
That would make sense as the charger has it's own, distinct TT earth, which can't be mixed with the house earth, and any metalwork on/around the house may be bonded to that earth.

Although, that's a very simple thing for the installer to check ahead of installation.

Sheepshanks

Original Poster:

32,880 posts

120 months

Friday 3rd December 2021
quotequote all
48k said:
That sounds like a load of bobbins, or else there must be thousands of non-compliant installs in the country, including mine (installed last month).

Your set-up is exactly what I was assuming I'd be able to do, but now I'm not sure.

Maybe they consider the garage door isn't earthed to the house earth - mine has an electric opener but the door itself isn't specifically bonded to earth.


TheDeuce

21,906 posts

67 months

Friday 3rd December 2021
quotequote all
Sheepshanks said:
48k said:
That sounds like a load of bobbins, or else there must be thousands of non-compliant installs in the country, including mine (installed last month).

Your set-up is exactly what I was assuming I'd be able to do, but now I'm not sure.

Maybe they consider the garage door isn't earthed to the house earth - mine has an electric opener but the door itself isn't specifically bonded to earth.
If that's the case you have no issue - the issue would be crossing earth types. if it's not bonded, no issue. Although I assume the opener is earthed back to the board so if that's steel to steel bolted to the door then the door is effectively bonded too!

You can check yourself with a cheap multi-tester, probably about £10 from screwfix etc. Either way it probably shouldn't be an issue as the installer could (I think) put the entire garage to the TT rod they have to install in any case. That's what I assume at least - I'm sure a spark will be along at some point to clear up these details.

48k

13,189 posts

149 months

Friday 3rd December 2021
quotequote all
Sheepshanks said:
48k said:
That sounds like a load of bobbins, or else there must be thousands of non-compliant installs in the country, including mine (installed last month).

Your set-up is exactly what I was assuming I'd be able to do, but now I'm not sure.

Maybe they consider the garage door isn't earthed to the house earth - mine has an electric opener but the door itself isn't specifically bonded to earth.
My charger is also within 2.5m of next doors garage door. And just below a metal light fitting. And near to some metal arris rail brackets. I think there must be more to this alleged rule than simply "must be 2.5m away from metal things". Otherwise, like I say, there must be thousands of non compliant installations around the country, which seems difficult to believe.


Sheepshanks

Original Poster:

32,880 posts

120 months

Friday 3rd December 2021
quotequote all
TheDeuce said:
If that's the case you have no issue - the issue would be crossing earth types. if it's not bonded, no issue. Although I assume the opener is earthed back to the board so if that's steel to steel bolted to the door then the door is effectively bonded too!
The opener is earthed but, while there's probably an electical path to the door it won't be reliable because the only physical link is the slider thing going along the rail.

I'm not sure if these rules/regulations are recent - I only looked into it as one electicity company site says they may insist you replace any metal wall lights with plastic.


I might can the idea anyway as the builders have added £495+VAT to run the cable which they insist must be armoured even though it'll run through the house. I understand now why builders don't like supplying itemised quotes - if I'd thought to mention it at the outset I'd never have known the cost.

TheDeuce

21,906 posts

67 months

Friday 3rd December 2021
quotequote all
Sheepshanks said:
TheDeuce said:
If that's the case you have no issue - the issue would be crossing earth types. if it's not bonded, no issue. Although I assume the opener is earthed back to the board so if that's steel to steel bolted to the door then the door is effectively bonded too!
The opener is earthed but, while there's probably an electical path to the door it won't be reliable because the only physical link is the slider thing going along the rail.

I'm not sure if these rules/regulations are recent - I only looked into it as one electicity company site says they may insist you replace any metal wall lights with plastic.


I might can the idea anyway as the builders have added £495+VAT to run the cable which they insist must be armoured even though it'll run through the house. I understand now why builders don't like supplying itemised quotes - if I'd thought to mention it at the outset I'd never have known the cost.
An installer will be able to confirm if the door is earthed anyway - it'll take them moments, assuming they think it is even an issue by the regs.

I'd get a couple of installers to look at it and provide quotes. At the end of the day, other than miniscule perceived safety risk (IE you're live whilst handling the cable but don't realise it and then decide to grab the automated garage door that you don't need to grab because it's automated...) your only concern is having the notifiable works reported and certified appropriately. If the installer is happy to install it where you want, that's the end of it regard your responsibility or future concerns when you sell the house. If it does somehow get picked up as technically not correct, you go back to the installer who is duty bound to correct their work - it's a bigger issue for them as a professional to get it right as it is for you as a layman customer. It's their knowledge and professionalism that you're paying for.


tendown

85 posts

132 months

Friday 3rd December 2021
quotequote all
It's to do with PEN faults where earth could become live, so if you have a "different" earth nearby you might get a shock.

This "different" earth happens because many ev charger installations had an earth rod installed to make sure the car had the same earth as the ground nearby, which could be a different earth to the rest of your house (taps/lights/garage doors).

As mentioned above the regs have been updated so you typically don't need to fit a earth rod any more, but a voltage sensing device can be used to sense the fault. This is easier for the installer so seems to be the most common solution I've seen. Technically it's not as effective as a well installed rod, but it's compliant with the regs.

In summary, it's fine to have it next to something metal now. Who knows if the regs might change in the future, but I'd be surprised if they cause you a problem since your situation is very common.

jason61c

5,978 posts

175 months

Saturday 4th December 2021
quotequote all
You’re getting totally shafted at £495+vat just for the cable.

Unless it’s a 150m run?

Sheepshanks

Original Poster:

32,880 posts

120 months

Saturday 4th December 2021
quotequote all
tendown said:
It's to do with PEN faults where earth could become live, so if you have a "different" earth nearby you might get a shock.

This "different" earth happens because many ev charger installations had an earth rod installed to make sure the car had the same earth as the ground nearby, which could be a different earth to the rest of your house (taps/lights/garage doors).

As mentioned above the regs have been updated so you typically don't need to fit a earth rod any more, but a voltage sensing device can be used to sense the fault. This is easier for the installer so seems to be the most common solution I've seen. Technically it's not as effective as a well installed rod, but it's compliant with the regs.

In summary, it's fine to have it next to something metal now. Who knows if the regs might change in the future, but I'd be surprised if they cause you a problem since your situation is very common.
Thanks. Bit of a minefield, I think - lots of discussions / opinion about the effectivenessof different solutions. I noticed 'earth rod built in' on quite a lot of chargers now - I wondered what that meant (as obviously you can't build in an earth rod) so I assume they're using some kind of PEN fault detector.

Sheepshanks

Original Poster:

32,880 posts

120 months

Saturday 4th December 2021
quotequote all
jason61c said:
You’re getting totally shafted at £495+vat just for the cable.

Unless it’s a 150m run?
I exaggerated a little - just looked and it's £425 + VAT.

Yes, it's completely bonkers - looks like it's around £45 for the cable. I did query it with the builder and he looked hurt.

I backed off as the quote for the job as a whole (£148K+VAT) is less than we were expecting. There's some slightly concerning lack of detail but when I've queried stuff everything I've asked him is included - "replace roof" apparently includes new facias, guttering etc, which I didn't expect.

blank

3,465 posts

189 months

Saturday 4th December 2021
quotequote all
Any rule against putting one near a gas meter?

Ideal spot for mine would be on the side of the garage but this is also where the gas meter is...

Jonny_

4,135 posts

208 months

Saturday 4th December 2021
quotequote all
blank said:
Any rule against putting one near a gas meter?

Ideal spot for mine would be on the side of the garage but this is also where the gas meter is...
Hope not as they installed mine about 6 inches from the gas meter!

Pistonsquirter

329 posts

40 months

Sunday 19th December 2021
quotequote all
Interesting read - I am replacing my kitchen floor amongst other things and thought installing an EV supply while I’m in there was a good idea - just ordered 7 meters of 10mm2 3-core swa to pull in from the consumer unit to the external wall ready for an EV charger - will fit an ip67 external socket for now until I decide which charger to get, (10mm2 conductors means a fast one) for reference this cable was £30 delivered.
Need to check on heights really just for disabled access (assuming that applies)
I have a feeling it will need its own isolator and RCD for a fast charger’s current?

Sheepshanks

Original Poster:

32,880 posts

120 months

Monday 20th December 2021
quotequote all
In the absence of other answers:

Based on what I looked up 10mm seems OTT - 6mm should be plenty and even 4mm would likely be OK. Max charging is 7kW.

There's also special cables with two signal wires for a current transformer - I think so EV charging can be limited if the house is taking too much juice - and I saw one cable with ethernet in too, which might be handy in my case as wifi could be pretty ifft where I want the charger.


Sometimes the cable does just seem to be connected to the board through a 32A MCB - but electricians talk about using different types (letters) of MCB and RCD.