Consumer unit for EV charger and garage

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Hi,

I would like to buy a consumer unit for my garage where a 17mm thick 3-core SWA cable has been left by the previous owners. The other side of the cable is at the main consumer unit, This cable is currently not connected at either ends. Does 17mm overall cable thickness give any indication of thickness of cores inside?

The requirements for the garage are:
1. Couple of interior LED battens
2. Two interior sockets
3. Two exterior sockets
4. Three exterior PIR LED flood lights
5. An Electric Garage door
6. A type 2 (7 KW) EV charger
7. Future capacity for an extension above the garage (should be ~6 sockets and spot lights)

Can someone please help me get the right consumer unit? I am especially concerned about the EV charger and want to get the correct setup for EV installation in the near future.

A picture of main consumer unit added, please note that there are no electric showers or electric cooker in the house.
1712840056590.png


Many thanks in advance.
 

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Normally one can find the size of the cable written on its side, however as far as EV charging goes some how it needs to monitor how much power the rest of the installation is using.

There are many way to do this, but the popular way is to use a special cable with cores for the sensor.

Also there is a problem with RCD protection, nothing else should use the same RCD, and there are so many EV connection units, with so many ways to do the same thing, it has become a specialist subject, and things like method of earthing can completely change what is required.

So only thing you can do is install a duct to draw the cable through. So may as well forget the EV charging point until your ready to buy or rent an EV.

Just use the cable you have for now. It will need testing, likely cheaper to get a scheme member spark than DIY.
 
So only thing you can do is install a duct to draw the cable through. So may as well forget the EV charging point until your ready to buy or rent an EV.
There is no scope of installing another duct. The SWA cable in the picture is available in the garage where EV charger is going to be installed on the wall on the outside.
I need to know:
1. What consumer unit to buy for the garage?
2. Anything to add/ modify on the main consumer unit?
 
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1. What consumer unit to buy for the garage?
One with a main switch, surge protection of the required type, a quantity of RCBOs one for each circuit, and several blanks to fill the spare ways.

However you buying a consumer unit and expecting someone else to install it is not going to work.
Neither is you installing it and expecting someone else to test and notify the installation.


2. Anything to add/ modify on the main consumer unit?
Sling it away and replace with a new one.
Or possibly modify the existing one to add surge protection and somewhere to connect the armoured cable for the garage. As none of the circuits are labelled, impossible to know without further investigation. Many other details missing such as the type and size of the supply, connected loads, is equipotential bonding present and correct, size type, length, condition of that cable to the garage and so on.
 
This isn’t really DIY work and EV points have a whole section of the regs dedicated to them

My advice would be to locate a local spark WHO DOES EV points and use them

Are you aware that EV points need internet connections to?

And the size of your main fuse might be an issue too
 
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As a retired electrician, unlikely I would fit my own EV charging point, looking at around £100 plus vat to notify if the LABC will accept the installation certificate from you, if not could easy exceed £250 to go down the DIY route, that is a good chunk of the money you would pay a scheme member to do the work, so simply not worth doing as DIY.
 
Thanks for all the replies.
Even though I never mentioned that I am planning this as a DIY job, I repeat that the current plan is to buy and install a new consumer unit in the garage that would be used to run the lights and 13A sockets in the garage only.

I don't have an EV vehicle and not planning to buy one soon, but would like my consumer unit(main + garage) and associated wiring to be ready for when the time comes.
 
Many other details missing such as the type and size of the supply, connected loads, is equipotential bonding present and correct, size type, length, condition of that cable to the garage and so on.
The armoured cable is 3-core 6mm one. The current consumer unit could be as far as 8-10 meters from the new planned consumer unit in the garage.
There are no electric showers, the cooker is a gas one too. There is an electric oven but it is seldom used.
Attaching a pic of the main consumer unit with face off. As you can see there is plenty of space for SPD. Can the armoured cable can go to 40A MCB which is blank?
 

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I see no reason not to use the existing 40 amp MCB. And since consumer unit is metal, a SWA gland should not be a problem direct into the CU. As to if re-energising an old circuit is considered as a new circuit, you read the part P yourself and make up your own mind.

To my mind if you have the skill to complete the installation certificate then there is really no problem, they are a free down load from the IET web site. It details what you need to test, by having boxes to enter the results.
 
To my mind if you have the skill to complete the installation certificate then there is really no problem, they are a free down load from the IET web site. It details what you need to test, by having boxes to enter the results.
Everyone is a sparky until things go wrong :)
I've no intentions of playing with a consumer unit (or installing an EV charger myself).

The best I can offer is to put the battens and sockets up and line the cables in/ around the garage. The electrician would do the rest of job of modifying the existing consumer unit and installing the new one in garage.

But I do want to get the best materials for the job before I book an electrician.
 
Much as I respect your abilities. The person who is experienced in these matters is the electrician who is doing the job.
The thing that most electricians hate is customers buying a pile of stuff from one of the "sheds" and expecting the spark to make the best of it.
In my experience customer purchased equipment is quite often wrong/not fit for purpose or its stuff that is almost impossible to install or you take one look at it and KNOW that it isnt going to last long.

In these cases I'd switch from fixed price to time as I KNOW that I'm going to have to go to my supplier and get the right things, and/or charge waiting time while the customer trails back to Screwfix etc to exchange the tat for the right thing.

Personally I just won't do it

There are VERY specific requirements for EV installations.

You wont save any time or money going the route tou have in mind. Find your REGISTERED and
COMPETENT electrician and ask him/or her what (if anything) you could provide, and that includes manual work.
 
I can't work out if you want an EV charging point or not? One minute advising with the next without.

I agree with @Taylortwocities it is annoying when one arrives on a job to be presented with obsolete stock from one of the sheds which one knows one should not use.

And travel is expensive, to arrive at a job which must be aborted due to wrong materials is expensive. If one spends an hour in the van, that is still some thing which needs paying for some way.

The question to tradesman is there anything I can do to reduce cost is fair, but once agreed it does need doing on time.
 
But I do want to get the best materials for the job before I book an electrician.

But who is to say what the best materials are?

Ask 10 sparks and you'll probably get 8 answers

Ask 100 DIYers and you'll get lots of cheap carp suggestions

Find a spark first is my advice .........

And I never sign off or connect a DIYers work either ........
 

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