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2 electricity supplies to one building

Former Community Member
Former Community Member
Hello, I am a not an engineer but need some advice on uk wiring regulations please. 

A national utility company is fitting a 32A charger in my garage for an electric vehicle. 

The garage is detached from my house but there is an existing circuit from the house consumer unit to the garage for lighting and a power socket. The cable runs along a garden wall. 

The new charger will have its own cable run from the same consumer unit in the house down to the garage. 

My problem is that the engineer who came to do the installation refused to do it as he said the garage is a building in its own right and regulations do not allow 2 supplies to one building.

My question is: Do 2 wiring circuits from the same consumer unit constitute 2 supplies If the consumer unit is located in an adjacent building? 

I would have thought that this was still a single supply and to have 2 supplies you need 2 separate meters with 2 consumer units which is not the case here but then, as I said, I’m no engineer. 

Edit.....The engineer stated that the regulation related to avoiding the risk of a voltage between 2 different earths. To me this again only makes sense if you were talking about 2 totally different supplies from different meters and therefore possibly different sub stations etc.
Parents

  • Has the anti-EV brigade taken over this forum?


    There's no problem running an EV charger off an 80A supply.  Or a 100A supply that can only supply 100A for short periods.



    True. and not anti EV,

    But... 

    someone  will need to pay to upsize  the transformer after there are more than perhaps the first 6-10  houses per phase of the substation that have EV commuters.

    It will become vitally important to understand ADMD (and also DNO cable ratings - see pages 8-13 ) - this is not like adding electric showers that are each on for 15 mins at a time tops.

    You may not realise that round here a typical housing estate 500KVA lump will feed ~ 200 single phase properties each with 100A fuse, and most built up areas will be similar. Out of town the pole pigs that feed a couple of farm houses may do better, as the smallest Tx they install these days are either  25kVA or 50KVA split phase, even if only for a couple of properties.

    M.


Reply

  • Has the anti-EV brigade taken over this forum?


    There's no problem running an EV charger off an 80A supply.  Or a 100A supply that can only supply 100A for short periods.



    True. and not anti EV,

    But... 

    someone  will need to pay to upsize  the transformer after there are more than perhaps the first 6-10  houses per phase of the substation that have EV commuters.

    It will become vitally important to understand ADMD (and also DNO cable ratings - see pages 8-13 ) - this is not like adding electric showers that are each on for 15 mins at a time tops.

    You may not realise that round here a typical housing estate 500KVA lump will feed ~ 200 single phase properties each with 100A fuse, and most built up areas will be similar. Out of town the pole pigs that feed a couple of farm houses may do better, as the smallest Tx they install these days are either  25kVA or 50KVA split phase, even if only for a couple of properties.

    M.


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