Adding a garage supply inc EV charger

Joined
3 Aug 2020
Messages
25
Reaction score
1
Country
United Kingdom
Hi just wondered if I could have some advice please without having my head bitten off about having power installed I'm my garage, I have posted on another well known forum and have had allsorts of abuse without actually getting any advice so is this forum for DIY or is it just for " qualified electricians to chat to each other " as I have been told on the other forum !?
 
Sponsored Links
Joined
15 Jun 2021
Messages
1,967
Reaction score
453
Location
Wales
Country
United Kingdom
For a properly considered response, you may wish to state the issues that you wanted advice about! :)
 
Joined
12 Jan 2014
Messages
4,322
Reaction score
622
Location
Essex
Country
United Kingdom
as grinch said,

ask what you want advice about.

The electricians on here are mostly helpful, as are the plumbers, however if you start asking questions regarding a new circuit and not getting in a pro they will state regulations and such and provide little to no assistance, as do the gas engineers when people start talking about opening up there boilers.
 
Joined
3 Aug 2020
Messages
25
Reaction score
1
Country
United Kingdom
For a properly considered response, you may wish to state the issues that you wanted advice about! :)
Can I just firstly state that I am not connecting or terminating anything, a local Electrician in my village that I know wouldn't say friends but as we work in a small village we both turn up on the same job sites ect we know each other, he has said if I get everything ready for him and mounted he'll terminate and sign of if he's happy to save us both time, he is fully booked for few months and I need the power up and ready for the charger installer, OK, so I am having a EV charger installed, I have a 2.5 swa already run to the garage that I know is not good enough, so I have run a 10mm SWA from the cupboard where my main CU is too the garage, its been buried and he has seen that and was happy for it to be back filled, Now where I am confused is he had said, he'd put a 40amp mcb in the main cu for the 10mm swa to another cu in the garage, 63amp rcd, 32 for car,16 for sockets and 6 for lights, all good I thought, now I have been told that is wrong and I need to either have a 50amp mcb and a 63amp A type rcd in the garage or the 40amp mcb to its own cu in the garage for the 32 and the charger on its own and then use the 2.5 already in there for a 2nd CU for lights and sockets , just wanted to know the best way thats all to tidy it all up, the 2.5 currently is just to a isolation switch with sockets, garage doors and lights on , it goes to an outside box where it continues in the house in T&E to the Main CU on a 16amo mcb
 
Joined
12 Jan 2014
Messages
4,322
Reaction score
622
Location
Essex
Country
United Kingdom
Firstly, and i presume all the calculations have been done.

i assume the charger is for an electric vehicle, and presumed to require less than than 50amps of current?

it is pointless having the 10mm feeding into an breaker in the garage if its connected to a breaker in the consumer unit, if the breaker goes in the garage it will also trip the breaker in the consumer, so you will be gaining nothing.

personally i'd have the 10mm terminating into a large isolator (assuming the 10mm is large enough) and then taking a supply from this to the 16 amp and 6 amp breaker for the sockets and lights
 
Joined
3 Aug 2020
Messages
25
Reaction score
1
Country
United Kingdom
I guess so, he came round and had a look at everything and said that's what he would need to do,the car charger company have said their feed will need to come from the 32amp MCB in a smaller CU or have its own CU connected to a minimum of 6mm swa hence why I thought what he had said would of been OK as the 10mm is bit overkill but it would tidy it all up in there with the sockets and lights on there own circuits as such but I was since told that having a 40mcb wouldn't be able to cope with the 32 for the charger , 16 sockets and 6 lights and if it was done that way it would need to be a 50amp mcb on the non RCD side of the main CU and then would have to make sure it was a 63 amp A type rcd in the smaller garage CU , I can't imagine he is wrong and knows what he's doing but I just wanted to clarify because I don't want to question him without any knowledge Annoy him and he doesn't do it and then makes it awkward on other jobs we might be at together in the future if you get me !?
 
Sponsored Links
Joined
15 Jun 2021
Messages
1,967
Reaction score
453
Location
Wales
Country
United Kingdom
Under-rated breakers aren't necessarily a problem. It depends on how much power you intend using!
If you are fully loading your circuits with a washing machine and tumble dryer in the garage, when your car is charging there may be issues.
As long as the cables are correctly specced, you can always upgrade the breakers if there are issues.
 
Joined
3 Aug 2020
Messages
25
Reaction score
1
Country
United Kingdom
No just a freezer in there on all the time , lights very rarely, garage doors couple times a day and lights on outside are on PIR and only if something comes up the drive, socket outside for hoover or pressure washer when needed, the car will be set to start charging at around 12.30 am till around 4.30am ( low rate time from my suppler) again this will probably only be twice a week.

Could you explain the rcd situation and does it have to have the Type A ?
 
Last edited:
Joined
3 Aug 2020
Messages
25
Reaction score
1
Country
United Kingdom
I appreciate everyone has their own way of doing stuff, on the other forum I was told by one he'd would do it totally different to what I had mentioned but why should he offer his advice to me for free!?! I think I just wanted to make sure that either way is safe as I don't want it done one way, messes up and the charger installers say it all has to be changed
 
Joined
15 Jun 2021
Messages
1,967
Reaction score
453
Location
Wales
Country
United Kingdom
We can give advice, but if there is any doubt, go back and ask the charger installers. They are the ones that could refuse to install at a probably expensive call-out charge.
Set out your proposal in an email to them, you then have things in writing should an issue crop up on install day.
 
Joined
3 Aug 2020
Messages
25
Reaction score
1
Country
United Kingdom
We can give advice, but if there is any doubt, go back and ask the charger installers. They are the ones that could refuse to install at a probably expensive call-out charge.
Set out your proposal in an email to them, you then have things in writing should an issue crop up on install day.
Yeah I have sort of, they have just said it would come from its own mini CU or the 32 side of the shared one, I think its more this 40 or 50amp mcb in the main CU and the A type rcd that I'm worrying over that's all
 
Joined
12 Jan 2014
Messages
4,322
Reaction score
622
Location
Essex
Country
United Kingdom
If your electrician is happy signing it off on a 40 amp breaker then just continue with that.

As with most things there is probably more than 1 way of doing it.

You could upgrade the breaker to a 50 amp breaker just incase you do find yourself 1 day using all the available power.

But essentially there isn't anything wrong with your proposed set of works.

As I said if your electrical guy who is signing it of is happy with it that's all that counts
 
Sponsored Links
Top