[meldrewreborn]

@geoffers

You may be better off fitting the cabling without a charger on the end. Advances in technology might mean your selected charge doesn’t suit any later occupier.

when the jubilee line was built in London tunnels were built under the strand eastwards in the expectation of a later extension. The extension when it eventually came took a different route towards Westminster!!

[geoffers]

Originally Posted by geoffers

Interestingly, I'm in the process of planning to have my (external) garage rebuilt and will be looking to incorporate an EV charge point with this

This is a very good video which describes the 10 most important points to consider when having an EV charge-point installed : it's not as simple as some may expect 🤔

In my case it looks as though I'm going to have to get the DNO to replace my incoming supply as I'm currently on a "Looped Service" shared with my neighbour.

Then, although my household consumer unit is up to the latest spec I'll probably need a separate dedicated EV consumer unit, either incorporating or in conjunction with a Surge Protection Device(SPD)

Also there will be the trunking/cabling required to run the supply cable out the back to the garage itself. I'll probably also run an ethernet cable for the charge point, rather than relying on wifi signal (which although probably OK, it's much better to have a hard-wired connection)

I though I'd do an update on the progress of the cabling in preparation for the future install of my EVSE, for the benefit of anyone considering this

In my case the EVSE will be in a garage at the rear of the garden, with the supply being routed from my main consumer unit to a brick-built shed in the garden, adjacent to the old garage (which is to be replaced).

1. I've had my regular electrical contractors in to route the cable from the main house CU to the shed - adding a surge-protected consumer unit feeding new sockets/lighting circuit to replace the existing (dodgy) supply 😃
   
   1. Although I'm sure they would have done all the drilling etc to route the cable, I volunteered to do this myself so I could do it exactly to my requirements (and probably saved a fair amount of cost).
   2. This involved drilling with a 30mm SDS drill, through 5 walls (2 being double skin thickness) and also digging a length of trench through a garden border to bury the SWA cable.
   
   
2. The incoming supply to the house is unfortunately looped with my neighbour, coming in to my meter cupboard before passing through to theirs
   
   1. I arranged for National Grid to do the "unlooping" which is a free service for EV installs, and although quoting > 4week timescale, came back with a date of only 2 weeks.
   2. Due to a slight misunderstanding, I had not appreciated that they had said it was my responsibility to organise for the trench to be prepared to expose the incoming cable.(Luckily not too deep 🤓)
   3. So a couple of days before the job it was down to the hire shop to rent a 12" petrol saw to remove a section of concrete path, before digging down to expose a section of the cable for a junction to be fitted to feed my neighbour.
   4. There is more work on the actual cabling for the neighbour as holes are needed into her property to route the new incoming main... for me they just disconnect the loop.

The actual EVSE installation is a long way off, but have been doing a fair amount of research.

Of significant relevance is the provision of a sound earthing point for the installation which many may not be aware of. There is quite likely to be the need of an earthing rod driven into the ground for protection, but since I'll be having a new concrete slab for the garage, I should be able to run an earthing point from the steel reinforcement in the slab.

There is a particularly good video here from John Ward (jwflame) discussing the earthing requirements/problems - worth watching the whole video, but about 30mins in shows the optimal solution using earthing to concrete rebar..

[DebF_EONNext]

@geoffers could you explain what you mean by looped with your neighbour? Does this mean that when your cables come out into the street that it's joined with your neighbours cabling? I have zero knowledge here so please get the crayon out for me 🖍

[geoffers]

Originally Posted by DebF_EONNext

@geoffers could you explain what you mean by looped with your neighbour? Does this mean that when your cables come out into the street that it's joined with your neighbours cabling? I have zero knowledge here so please get the crayon out for me 🖍

Quite often terraces & closely built houses have one incoming supply to house 1 (mine in this case) then a "loop" into house 2 so they effectively share the incoming supply.

It was a particularly bad original install in my case, since the neighbour's supply was connected AFTER my 100amp fuse, so we effectively shared 50% of a maximum 100amp supply, and if the supply fuse in my house had blown, my neighbour would have been cut off too. Their loop should have been taken off before the fuse.

Since EV chargers are rated at nominal 7kW which takes around 32amps - If both houses are charging at the same time that would use about 65 amps, leaving 35A for everything else - so in the unlikely event you both took showers, whilst boiling a kettle and cooking your dinner it could potentially blow your main fuse.

So a shared "looped" supply has to be un-looped where chargers are being installed. This is the final result ... to my mind not much has changed as we're still sharing the same main incoming cable, but it must presumably have a high enough current capacity



Apparently there are many cases where someone is about to take delivery of an EV, and getting the charge point installed only to find they can't have it put in until they get un-looped which could take many weeks

[meldrewreborn]

@geoffers

I'd not heard of this before. From your description the loop in your case would have been visible in your home - yes? If the split happens outside of your property then there is no particular issue, I imagine.

I can understand using one cable to approach 2 or more houses then splitting it closer to the houses saves on cable costs.

Equally the sewage arrangements in my area have one "foul" service running across the rear of 6/7 properties, and a Rainwater service collecting similarly from the front. Unfortunately both services combine later on!

[DebF_EONNext]

@geoffers thanks for explaining! @meldrewreborn I swear our pipework is linked like that 😂 the people next door to us only use their property as a holiday home but everytime they come back our drainage system goes belly up, the flush doesn't work and the bath, showers & sinks take an age to drain too. Then as soon as they leave it goes back to normal 🚿

[geoffers]

Originally Posted by meldrewreborn

@geoffers I'd not heard of this before. From your description the loop in your case would have been visible in your home - yes?

Yes - the service head (DNO fuse) in my meter cupboard had my neighbour's connection coming out of the top, and then through the party wall into her meter cupboard.

Ours was incorrectly routed since it should have come out of the bottom, (ie on the supply side, not the top which is on the fused side)

If my main fuse had blown whilst I was away it would have cut the supply to both properties, rather than neighbour's staying live if it had been connected at the bottom/supply side.

If you search on youTube for looped electrical supplies you'll see the more common service head with 2 cables at the bottom (rather than one) indicating it's probably a looped service

[geoffers]

Originally Posted by geoffers

This is the final result ... to my mind not much has changed as we're still sharing the same main incoming cable, but it must presumably have a high enough current capacity ...

Thinking about this a bit more...

Maybe the reason is that they are moving the risk of a potential cable overload from inside the house (= risk of 🔥🚒)... to outside and underground, on the DNO side of the cabling where they can easily repair any fault without your house burning down

[meldrewreborn]

@DebF_EONNext

For waste services, each property owner is responsible for their pipework until it joins the common sewer. Everything else is the responsibility of the sewage company - not you. I think a phone call is required.

[rwh202]

Originally Posted by geoffers

Yes - the service head (DNO fuse) in my meter cupboard had my neighbour's connection coming out of the top, and then through the party wall into her meter cupboard.

If you were your neighbour, then you'd be none the wiser and not know if looped.
If you are the end of the loop, there is no indication. Only the intermediates in the loop can tell, but sometimes the join / loop might be hidden.
Ultimately, the DNO holds the records of who's looped and who isn't which is why they get informed during EVSE install.
Even if they can't approve an unrestricted 32A EVSE, you can normally get approval for one restricted to 16A or one with load monitoring to prevent total house load below a limit if unlooping is impractical.