DNO incomer service cable hot during EV charge

[Domcoop777]

Had new EV charger fitted 7kw, on a 40A rcbo fed with 6mm twin & earth.

In use the DNO's service cable, two core lead sheathed gets hot to the touch. Like I'd estimate 70 degrees plus.

Their cable seems undersized - it's smaller than the 6mm T&E!

Please see pictures. Is this anything to worry about / contact DNO about?

 

[PS Electrics]

Had new EV charger fitted 7kw, on a 40A rcbo fed with 6mm twin & earth.

In use the DNO's service cable, two core lead sheathed gets hot to the touch. Like I'd estimate 70 degrees plus.

Their cable seems undersized - it's smaller than the 6mm T&E!

Please see pictures. Is this anything to worry about / contact DNO about?

View attachment 122152View attachment 122153View attachment 122154View attachment 122155

How long ago was this installed?

DNO should have been notified with regard to installing this and the new Max Demand.

The application should have stated main fuse size and Maximum Demand amongst other things.

Was approval given?

Do you have the EIC? (Electrical Installation Certificate)

 

[westward10]

I'm surprised that cable is still in service.

 

[UNG]

Looking at the incoming supply and service fuse it would appear the EV charger installer as mentioned above has overlooked some important stages pre installation like the DNO notification

 

[westward10]

Never seen a flat twin lead sheathed cable for a DNO supply I can't believe it connects underground must have been there since the 40/50s. I would report it as that earth connection cannot be relied upon plus those conductors should not be exposed.

 

[Domcoop777]

Looking at the incoming supply and service fuse it would appear the EV charger installer as mentioned above has overlooked some important stages pre installation like the DNO notification

Funnily enough I queried this at the time, as worried they may need to dig driveway up or refuse permission.

He said as the charger can ensure house load doesn't exceed 60A they don't need permission just to let the DNO know.

I did ask how comes then the charger has a 40A supply and my double oven does (which makes 80A) and the consumer unit has 100A main breaker, but he assured me it doesn't work like that.

I called them when I felt the hot incomer and they said to contact my electric supplier (Octopus) which seems obviously wrong so doesn't fill me with confidence!!

 

[littlespark]

If you continue to use the ev charger, there is a serious risk of fire.

The incoming cable is undersized, and needs replaced. The installer should never have fitted it.

 

[westward10]

I don't think any competent electrician would have installed an EV point with that supply.

 

[Domcoop777]

If you continue to use the ev charger, there is a serious risk of fire.

The incoming cable is undersized, and needs replaced. The installer should never have fitted it.

Thank you! In fairness this is what I thought. I'm surprised EV installer didn't raise it nor, before him about 5 years ago when we had kitchen fitted and new Consumer Unit put in. (you can see in the photographs where the last sparky pulled the DNO fuse because the seal is cut and not replaced).

 

[PS Electrics]

Funnily enough I queried this at the time, as worried they may need to dig driveway up or refuse permission.

He said as the charger can ensure house load doesn't exceed 60A they don't need permission just to let the DNO know.

Technically that is correct but to do that they would have to be certain on a number of issues these are addressed in the ena (energy networks association) work flow.

I would have serious concerns looking at that supply though.

For the charger not to exceed the 60A supply curtailment must be installed and functional.

Have you any documentation from the installer that they considered such things as MD etc?

Did you get an Electrical Installation Certificate?

I did ask how comes then the charger has a 40A supply and my double oven does (which makes 80A) and the consumer unit has 100A main breaker, but he assured me it doesn't work like that.

I called them when I felt the hot incomer and they said to contact my electric supplier (Octopus) which seems obviously wrong so doesn't fill me with confidence!!

 

[Rockingit]

Cut out the nonsense middle men - report it as an electrical danger emergency then turn it on to get hot….

 

[UNG]

Technically that is correct but to do that they would have to be certain on a number of issues these are addressed in the ena (energy networks association) work flow.

It is only technically correct if the 7kw chargepoint is limited to 3kw by the installer and cannot be changed by the homeowner / user and that was a limitation placed on one of my installs recently until the DNO could unloop my customers supply and upgrade the street network, after a second DNO survey they are now installing a 3 phase supply at my customers property while only one phase will be used

I would have serious concerns looking at that supply though.

For the charger not to exceed the 60A supply curtailment must be installed and functional.

Have you any documentation from the installer that they considered such things as MD etc?

Did you get an Electrical Installation Certificate?

I would agree with what you have said although with regard to load curtailment while there is a 60A main fuse the network diversified load assessment will be way below the 60A and more like 15A which is why the DNO have to be notified due to the time / load profile a 7kw EV chargepoint places on the supply cable and the local network

The install as it stands may cause the OP problems as the DNO could I believe disconnect his supply on the grounds of safety under the ESQCR, I would suggest until DNO approval is sought and approved he places a 13A / 3kw limitation on the chargepoint

 

[diditrain]

Maybe do your charging overnight, when you are not using much power for anything else, until the issue is resolved.

 

[7029 dave]

That needs reporting to the DNO asap