EV Charger Questions

[Numbfoot]

Hi, hope you guys can help with a few basic questions about EV charger installations.

I'm assuming they have to have a dedicated feed to the CU with a 32A breaker - this is for a 7Kw charger - and I think that means a 6mm cable.

If I run that under the floorboards does it need to be in SWA?

Once through the house wall what are the regs about how the cable is run? Are there height requirements etc.

My CU is under the stairs in the middle of a semi-detached and we've solid wood flooring so access will be an issue.

Needless to say I won't be doing this work but want to understand options rather than have to accept the quickest, easiest option for the installer. Don't want it looking like a dogs dinner if I can help it.

Thanks

Paul

 

[Phoenix]

Yes its dedicated circuit back to the board
Generally 6mm but may need to be bigger in some circumstances.
In most situations you need a twisted pair of signal wires with it for the CT clamp for the maximum demand protection
Desn't need to be SWA unless its being buried, but if its going outside, needs to be UV stable, NYY-J cables are often used
Shouldn't be downstream of any type AC RCD, requires its own double RCD, and is inadvisable to be downstream of the same rating of A RCD - This often means a replacement or additional board is required - pictures of the existing would help confirm this.
There are often ways to route cables which can be found on site, is it just the ground floor thats got laminate, or the first floor as well?

Bear in mind, the national companies(often twinned with energy or car car firms) like to try and do as near enough a standard install as they can and give one man about half a day to get it in, this sometimes ends up with it not being routed as you'd prefer, often you'd be better going with a local firm who do EVSEs alongside most other electrical work, who are probably more flexible in your approach

 

[binky]

Do you have an external meter box, it can be easier to run from that sometimes.

 

[Numbfoot]

Do you have an external meter box, it can be easier to run from that sometimes.

Unfortunately not, that would be a neat solution.

 

[Numbfoot]

Yes its dedicated circuit back to the board
Generally 6mm but may need to be bigger in some circumstances.
In most situations you need a twisted pair of signal wires with it for the CT clamp for the maximum demand protection
Desn't need to be SWA unless its being buried, but if its going outside, needs to be UV stable, NYY-J cables are often used
Shouldn't be downstream of any type AC RCD, requires its own double RCD, and is inadvisable to be downstream of the same rating of A RCD - This often means a replacement or additional board is required - pictures of the existing would help confirm this.
There are often ways to route cables which can be found on site, is it just the ground floor thats got laminate, or the first floor as well?

Bear in mind, the national companies(often twinned with energy or car car firms) like to try and do as near enough a standard install as they can and give one man about half a day to get it in, this sometimes ends up with it not being routed as you'd prefer, often you'd be better going with a local firm who do EVSEs alongside most other electrical work, who are probably more flexible in your approach

Thanks for that, much appreciated, not having to have SWA threaded under the floor is a relief. It's likely to be fitted as part of the car deal and it's exactly the time pressure compromises I want to avoid.

 

[mainline]

Do you have an external meter box, it can be easier to run from that sometimes.

“While the meter cabinet is the customer’s, it is a space designed for the use of electricity industry apparatus only and no allowance is made for additional equipment. For safety reasons, we would not recommend that any internal wiring, including a consumer unit, is installed within the cabinet.”
Energy Networks Association

 

[Murdoch]

Dedicated circuit, dedicated RCD

 

[Murdoch]

Thanks for that, much appreciated, not having to have SWA threaded under the floor is a relief. It's likely to be fitted as part of the car deal and it's exactly the time pressure compromises I want to avoid.

But a cable will be needed back to the CU - best avoid joints is my advice

 

[SPECIAL LOCATION]

It's likely to be fitted as part of the car deal and it's exactly the time pressure compromises I want to avoid.

I think your concerns are very valid!

Does the "car-deal" package include a pre-installation site visit to assess the existing supply arrangements and discuss preferred installation methods etc.. ?

If not.. having electrics installed via your choice of car supplier, is a bit like having B&Q or Wickes or IKEA fit your kitchen and do the electrics & plumbing etc.. Where generally their contractors arrive on site, with no prior knowledge, but have to operate under strict cost & time allocations.. Which never seems to allow for 95% of the typical anomalies that can arise during electrical alterations and/or additions!

Plus if there are any later problems your contract was never with the person who actually did your work..
It is with the garage / car showroom etc..

From my past experience I've tended to notice that any contractor who knows they will probably never be the person returning to resolve any later faults, typically does not put as much time, effort and/or pride into their work to get it right first time and acceptable to the customer... All they worry about is if it is working now.. can I get my money.. and where's the next job?


Key points you need to remember:-
There are multiple solutions to all electrical work, that will all comply with wiring regulations, so different electricians can all provided different solutions.

The various solutions can be affected by the selected material costs, time required, if cables need to be concealed or visible, the structure of the buildings.. etc.. etc..

As with numerous sectors of business, if you have contract(s) directly with the person providing some goods or services then you will typically have more control over exactly what is done and/or getting them back if it was not done properly first time..

If your contract was via a third party then you could get multiple different sub-contractors returning to resolve any problems, who are also under strict costs / time guidelines, but have little or no prior knowledge of your previous issues!!

As has been mentioned earlier SWA with CAT 5e data cable is available...
https://www.cef.co.uk/catalogue/pro...szh-ev-cable-black-cut-length-sold-by-the-mtr
Which may help with your understanding if you did choose to get some independent quotes for an EV charge point.

Also it may be worthwhile having a re-read of exactly what they say they will provide for your EV charger??