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EV Charger TT arrangements for private drive close to highway apparatus

Hi All.

I have a situation where a resident has requested the installation of an EV Charger to their domestic premises which has a driveway.

The company installing (Large well known French energy provider) has refused to install the EV Charger as they have identified that there is a street lighting column located within 2.5m of the driveway with a PME service installed.

Whenever we have EV CHargers installed on the Highway we use a TT service and any associated street furniture located within 2.5m of the parking bay is also converted to a TT system. However - as this is a private household and the street light is already in situ it has caused an issue.

I have read the BS7671, 4th Edition of the Electric Vehicle Charging Equipment Installation and other relevant documentation but this apparently seems to be omitted from all publications. (Or have I missed something?)....  This is the first instance we have received of this nature but no doubt it will not be the last.

Any advice / comments welcommed.

Regards

  • It sounds like the answer is to find another installer who will install a modern charger with open PEN detection.  Get an installer who can self-certify, so they will generate the correct paperwork.  The customer is happy, the council's building control department are happy.  And don't ask anyone for permission first.

  • Is the house on the same PME supply as the house?  If so, then what's the problem

    The house and lamp-post being on the same PME systems isn't a complete solution.

    The ground the ground the EV will be stood on isn't (reliably) part of the PME earthing systems - hence a risk of shock from the EV to true Earth during open PEN events - so BS 7671's requirement for some other approach (open PEN detection, TT etc.).

    Then if there is an open-PEN event, the break could well be between the house and lamp-post (there seems to be an assumption in the calculations in BS 7671 (e.g. for additional electrodes) that the break affects just one installation).

    I guess there's an assumption that cars are more likely to be touched, and less likely to have adequate additional electrode than lampposts.

        - Andy.

  • We have an issue as the local DNO, who do not currently recognise anything but the TT method of earthing

    Might be worth a challenge ... it seems to me a DNO would be on a sticky wicket refusing a supply to an installation that complied with current 'British Standard Requirements' as the ESQCR puts it (i.e. BS 7671).

       - Andy.