Smart charger or not?

[BugEyed]

The current "fashion" to save a few pennies for the developer is to place the meter and the consumer unit in the centre of the house. It may be the same for you, but the correct question is where is meter? What is the construction of your house, solid or timber suspended floor?

 

[Rg5]

Sorry meter and consumer unit both under stairs in the middle of the house. Timber suspended floors

 

[BugEyed]

You cannot take a feed from before the meter so it's irrelevant how it gets there. Yours sounds a non-standard install. What are the construction of your ground and first floor, and which way do the joists run (eg in the direction you want the wire to go or perpendicular to it)?

 

[Rg5]

Joists run in direction of the metre from where I want the wallbox installed both ground and first floor. Only issue would be the wooden floor laid in the hall preventing floorboards being lifted but could lift carpet and boards in the room directly next to wallbox and the understairs cupboard. With an approx metre wide hall inbetween

 

[BugEyed]

Sorry for the 20 questions approach, but is the internal floor level above the finished ground level outside such that you'll be able to get the cable into the house from outside and under the floor without compromising your damp proofing? If so downstairs sounds best, otherwise up is the alternative. You may want to separate the job into two and get a contractor to install some approved cable and just get the charge point installed Sparky to connect it at both ends.

 

[Rg5]

Not at all I appreciate the advice. Internal floor sits about a foot above the tarmac on the drive. I double checked and joists are actually running front to back of house on ground floor but there's a fair bit of room beneath them. Assuming electrician will deliver bad news about extra costs when he comes out on Thursday or Friday. I can tell its not going to be a simple job.

 

[Douma]

Personally I'd go tethered rather than untethered for security and convenience unless I have a regular need to charge the increasingly small proportion of cars with a Type 1.
I would not bother with a "smart" charge point unless you want to go onto a time of use tariff (such as Agile) - it's simple to modify a dumb one to run to fixed times.
I'd recommend a dumb charge point with discrete components such as Viridian as the life of some of the "smart" ones is not as good as the cost justifies, and there's too many suppliers in the market to guarantee the survival of any one. Others like PodPoint charge so much for a callout that repairs aren't economic

Personally I'd go tethered rather than untethered for security and convenience unless I have a regular need to charge the increasingly small proportion of cars with a Type 1.
I would not bother with a "smart" charge point unless you want to go onto a time of use tariff (such as Agile) - it's simple to modify a dumb one to run to fixed times.
I'd recommend a dumb charge point with discrete components such as Viridian as the life of some of the "smart" ones is not as good as the cost justifies, and there's too many suppliers in the market to guarantee the survival of any one. Others like PodPoint charge so much for a callout that repairs aren't economic.

My own 'Dumb' charger is supplied by Veridian & it does what it says on the box, plug it in to the car & following all the necessary handshakes my car gets a charge.
No smart meter for me, NO THANKS.
MG5 sr (2021)

 

[BugEyed]

Assuming electrician will deliver bad news about extra costs when he comes out on Thursday or Friday. I can tell its not going to be a simple job.

It doesn't sound too difficult. Offer to take up and reinstate the floor boards etc.
What form of Earth does your house have? Does it say PME on the head?

The picture above is a typical PME with the Earth being provided from one of the concentric conductors of the supply. Do you know the size of the main fuse fitted (not the capacity of the service head) at C and do you have a main isolator around H on the picture?

 

[Rg5]

There's an earth cable going into the main black box. It says 80a on it too so assuming it is 80 amps supply to house. Pic below of my supply

 

[BugEyed]

I hope that is genuinely the fuse fitted, it may just be the maximum rating of the unit. The danger is that depending on your other loads you may need load limiting.
In terms of Earthing it's not possible to see from that picture but what you describe sounds as if you will need Open PEN protection as well as an additional RCD and circuit breaker.

 

[Rg5]

Im going for a hypervolt unit which has built in pen protection and load limiting

 

[Rg5]

Thanks for all your knowledge bugeyed. Gives me a bit of pre loaded knowledge before speaking to the electrician in person

 

[5teep]

My house is also a 1970s build and the fuse box and electric supply are under the stairs in the middle of the premises. Does anyone know what way this is wired through the house? Is it under floorboards or will I have an armoured cable running along some walls?

That depends entirely on the the make up of the house and what you want.
My situation was the same, the floor under the stairs is solid concrete so my cable had to take a partial route on the surface until we got to the edge of the concrete then we could lead it under the floor the rest of the way, exiting via an air brick near where I wanted the box to go.

 

[Rg5]

Fortunately my entire downstairs is joists and floorboards and probably a foot above the driveway so hopefully will be able to drill through then route cable under floorboards. But just be whether electrician will want to charge an arm and a leg for it otherwise I could possibly do that bit and he can wire it either end

 

[5teep]

Fortunately my entire downstairs is joists and floorboards and probably a foot above the driveway so hopefully will be able to drill through then route cable under floorboards. But just be whether electrician will want to charge an arm and a leg for it otherwise I could possibly do that bit and he can wire it either end

I did that part myself (am able and have the right gear to do it). So all the sparkie had to do was attach the cable to my pull through and umm pull it through

 

[Rg5]

I'm going to lift a few floorboards before he comes and either route it whilst he works on other bits or hopefully hell be happy enough with me pre arrival effort and crack on, or get him to leave me the cable and come back and connect it all up

 

[5teep]

Any sparky is going to love you for doing the hard part before he gets there. Leave a pull through and a hole at either end that is quite a lot bigger then you think you'll need. For some reason electricians like to tie lots of string round the end of the cable they are pulling.

 

[Alb]

A professional electrician would use a cable sock.

 

[BugEyed]

For some reason electricians like to tie lots of string round the end of the cable they are pulling.

A professional electrician would use a cable sock.

Indeed. But if you have run a pull rope to attach the sock to they be very happy.

 

[Lovemyev]

As a unrelated side note topic, that could be addressed at the time of the EV install.
That currently installed twin and earth cable that is entering into the top of your steel consumer unit, should have a cable gland fitted to the knock out hole in the top of the CU.