Mains Loopback

[Creakyride]

Hello everyone.
I have been told that a car charger installation at my home is not possible because the installer noticed that the mains is on a looped system. I have 2 black tails coming in my house. For this reason, the installer needs to contact the DNO to check if the cables have been already disconnected from the neighbours mains or if it needs disconnecting.

Currently there is a 100A fuse.

Can someone tell me if the loop is likely to be connected to the neighbour that I share the drive with? Or would be the neighbour I share the internal wall with?
I live on a semi detached house.

To me it would make sense that it would be the property across, that I share the drive with, as it would be a very short cable run between the two houses.

That neighbour, told me that he has only one black mains tail going in to his house and that many years ago the electricity board upgraded their mains fuse from the previous 40A to 100A. The thing is... I don't recall ever seeing anyone digging a new mains cable in, which I assume it would need to be done.

Has anybody had experience in this type of work?

 

[Andy™]

only DNO can confirm that. everything else would just be a guess

 

[SPECIAL LOCATION]

Hello everyone.
I have been told that a car charger installation at my home is not possible because the installer noticed that the mains is on a looped system. I have 2 black tails coming in my house. For this reason, the installer needs to contact the DNO to check if the cables have been already disconnected from the neighbours mains or if it needs disconnecting.

Currently there is a 100A fuse.

Can someone tell me if the loop is likely to be connected to the neighbour that I share the drive with? Or would be the neighbour I share the internal wall with?
I live on a semi detached house.

To me it would make sense that it would be the property across, that I share the drive with, as it would be a very short cable run between the two houses.

That neighbour, told me that he has only one black mains tail going in to his house and that many years ago the electricity board upgraded their mains fuse from the previous 40A to 100A. The thing is... I don't recall ever seeing anyone digging a new mains cable in, which I assume it would need to be done.

Has anybody had experience in this type of work?

It doesn't really matter what any of us think as the cables coming into your property belong to the DNO.. They are not within the scope of BS7671 wiring regulations... And it is entirely up to the DNO how they want to configure the supply coming into a property and what earthing arrangements they are happy with..

SideNote#1:- Altering the rating of the main cut-out fuse may not need any changes to the incoming supply cable..

SideNote#2:- For 90%+ of the time, the electrical demand for the average domestic property is no where near their actual 'main cut out fuse' rating (e.g. 60A/80A/100A)..
More realistically it is below 10A!!! {So a couple of properties sharing a looped supply was not a problem}

SideNote#3:- The two big headaches for DNO's now are (a) People generating their own electricity and sending it back into the grid.. (b) People with significantly higher power demands e.g. wanting to get the EV charged back up ready for work or that long holiday trip!! And DNO's need to somehow ensure that too much electricity is not flowing up or down their cables to cause damage/fire/injury to anyone or anything!!!


If all cables disappear into the ground it is a pot-luck-guess trying to assume where they come from or go to???

Sometimes it is quite easy to workout which cables are the incoming feed and which ones loop to another property... e.g. with these two properties it was clear which cable looped out of the distributors cut-out, through the wall to the next door house...


But if you have two cables that both go down into the ground...
Then only the DNO can say, (Should be able to say), accurately!!!

It sounds like your charger installer has at least got sufficient knowledge to not just connect onto your supply without first verifying the condition and characteristics of the existing incoming supply.

Basically you are going to need to wait for the results of his enquires?

 

[UNG]

Hello everyone.
I have been told that a car charger installation at my home is not possible because the installer noticed that the mains is on a looped system. I have 2 black tails coming in my house. For this reason, the installer needs to contact the DNO to check if the cables have been already disconnected from the neighbours mains or if it needs disconnecting.

You don't say what the load or capacity of the EV chargepoint is

Currently there is a 100A fuse.

While the fuse carrier may say 100A on it the fuse that is fitted could be a lot less than that

Can someone tell me if the loop is likely to be connected to the neighbour that I share the drive with? Or would be the neighbour I share the internal wall with?
I live on a semi detached house.

To me it would make sense that it would be the property across, that I share the drive with, as it would be a very short cable run between the two houses.

There is no standard method I've seen semi detached properties where the supply is installed on the party wall and looped through the wall and others where they are looped across the drive and occassionally there is a tee under the drive with a single cable to each property

That neighbour, told me that he has only one black mains tail going in to his house and that many years ago the electricity board upgraded their mains fuse from the previous 40A to 100A. The thing is... I don't recall ever seeing anyone digging a new mains cable in, which I assume it would need to be done.

As my comment above, the old service head may have been replaced but without pulling the fuse you do not know what size fuse was fiited when it was installed

Has anybody had experience in this type of work?

Not done too much on EV chargepoints but I will always put the ENA form into the DNO before even considering an install

If you look at your installers comment about the looped supply it suggests he would have fitted an EV chargepoint for your neighbour with only one cable in the service head / cut out without checking with the DNO which is a bit worrying

I had a call from one of my customers a while back his next door neighbour was getting an EV company car and was having a chargepoint installed, the supply was looped and the DNO wanted permission to dig up my customers drive to unloop the supply, my customer had some concerns and called me to get a better explaination of what it meant, my comment was that as a minimum he needed to confirm that his supply would be suitable for an EV chargepoint when they finished the work and his drive would be reinstated to what it was before the dig. If they couldn't confirm his supply would ok for a chargepoint I would have put an ENA form into the DNO and got them to do any necessary work at the same time

 

[Creakyride]

Thanks everyone for your comments, I am awaiting to hear from the installers what the DNO says about it. Hopefully fully it gets resolved quickly.