UK New electric supply connection

wwilts · Jul 24, 2021

New 46kVA electric supply to new backland dwelling (37m from footpath). Mains cable runs along the footpath at the road access.
Which option would you choose and why?

Option 1

Meter box near footpath. Own fuse and armoured cable (>30m distance) underground to new dwelling.

Option 2

Meter box 25 m from footpath. Own fuse and armoured cable (<15m distance) underground to new dwelling.

Rockingit · Jul 24, 2021

46kVA to a dwelling?? Are you sure you actually mean that?

wwilts · Jul 24, 2021

Rockingit said:
46kVA to a dwelling?? Are you sure you actually mean that?

Yes.
Two phase.
Future proofing for EV chargers.

Question: meter box near mains cable
OR
25m from mains cable (with SWA provided by DNO)

Rockingit · Jul 24, 2021

With respect, I think you need to take a second look at your demand calculations. Post up exactly what it is that you’re looking at building.

wwilts · Jul 24, 2021

Rockingit said:
With respect, I think you need to take a second look at your demand calculations. Post up exactly what it is that you’re looking at building.

One dwelling
with up to 2 EV chargers
22kW fast x 2
43-50kW rapid x 1

Charging point can be located near external meter box if needed to simplify cable to dwelling

Trying to understand pros and cons of external meter box located near mains cable OR nearer to dwelling

westward10 · Jul 24, 2021

wwilts said:
Yes.
Two phase.
Future proofing for EV chargers.

Question: meter box near mains cable
OR
25m from mains cable (with SWA provided by DNO)

You mean three phase?

wwilts · Jul 24, 2021

westward10 said:
You mean three phase?

DNO states "dual phase supply installed into a secure waterproof cabinet provided and installed by customer"

timhoward · Jul 24, 2021

A simple sketch might be worth a thousand words with this one.

Rockingit · Jul 24, 2021

I'm assuming that you've already had the DNO quotation for the new transformer, etc etc?

wwilts · Jul 24, 2021

timhoward said:
A simple sketch might be worth a thousand words with this one.

Here it is. Option 2 could have EV chargers near meter box.
From meter box to dwelling could be usual domestic supply (eg. 11 kVA)

Rockingit · Jul 24, 2021

In the meantime, to answer your question, you want to get the DNO intake and meter as close to the property as possible - the simple reason being that as/if/when something goes wrong it's the DNO's responsibility to fix it, not yours!! Remember - you only own from the meter onwards.

Rockingit · Jul 24, 2021

From your pic, I'd strongly suggest you just get the DNO to quote for a new supply to the property. And if you really DO want that much energy, I'd just ask to get a 100/3ph installed instead - may well be cheaper and will certainly be safer and easier to deal with on site.

wwilts · Jul 24, 2021

Rockingit said:
In the meantime, to answer your question, you want to get the DNO intake and meter as close to the property as possible - the simple reason being that as/if/when something goes wrong it's the DNO's responsibility to fix it, not yours!! Remember - you only own from the meter onwards.

Great. Understood, thanks

brianmoooore · Jul 24, 2021

westward10 said:
You mean three phase?

If the DNO are talking two phase (230-0-230) then 3 phase may not be available. This has been a problem throughout most of my working area. Quite a few of my customers have two phase supplies, including myself, but I can count the number of customers I have with 3 phase supplies on the finger of my hands. Possibly just one hand.
In answer to the OPs question, definitely not option 1.