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Details of BS7671:2018 Amendment 1 are here.

Alan Capon
Details of Amendment 1 of BS7671:2018 is available here: https://electrical.theiet.org/bs-7671/updates/


Regards,


Alan.
  • 0
    Probably not worth re-designing Mode 3 charging at this stage, Mode 4 is already starting to become well established (this is a charger in the EVSE itself, and not the vehicle), and wireless charging is on the way. It's a fast-moving industry at present.
  • 0

    I think that if I was an EV manufacturer, I would be thinking that these bods in the U.K. are giving grief about the installation of charging points and I would set about building a vehicle that didn’t give a toss what the earthing system was.



    Given that cars are pretty much a global product, much of the world has a much laxer attitude to earthing than us, and the last thing any marketing department wants for a new product that's been hugely expensive to develop is any accusation of a new safety problem that's outside of the customer's control - I'm astonished they didn't in the first place.


      - Andy.
  • 0

    kenyon:

    It's a fast-moving industry at present.




    Which is precisely why I have made provision in my DB, but gone no further. However, I don't think that the purchasers of EVs think the same way. Perhaps we should salute the early adopters because without them, no progress would be made.

  • 0
    Hopefully the current types of wireless charging being trialled get designed straight back out again, as a really bad idea. There is already enough RF pollution as it is from things like badly designed solar farms without spewing stray kilowatts into the spectrum in among built up areas (current demonstrator designs have a link budget that  is about 90% - 94%  efficient, so for 10kW in, half to one kW comes out the side, just from the RF link perspective ). Right now it is only OK because uptake is very low.


    results from real tests like these    are suggesting that the makers have not really got a decent grip on it.

    From the measured results of charger ‘B’ between 30 MHz to 1 GHz, Fig. 17-22, we immediately observe that the level of EMI was significant and exceeded by far, especially

    in the vertical polarisation, both Class A and Class B limits.




    Class A is what you are allowed to do in an industrial setting, and is actually pretty rough, the lower B limit is for domestic, but even meeting this level is very far from saying it is RF quiet, just not likely to cause big problems beyond the immediate locality. Of course that assumes widely spaced sources of interference, not one in every 3rd house so you can never get far enough away.

    The designers should try and meet an emission standard that allows true co-existance with other services like NB30 or DEFSTAN 59 411 before they think it is ready, embedding a network of barrage  jammers even of a few watts radiated each into the community would not really be very civilised.


    Some of the  modelled levels    are hopelessly optimistic.




     


  • 0
    Is 722 not just a get out of jail card for DNOs? It is clear from this Section that no reliance can be placed on the neutral connection with earth yet 114.1 provides for the exact opposite.  Had there been no PME concern raised in 722, the onus would have remained squarely on them, at least for the domestic side of things.

    The clear implication in 722 is that regulation 114.1 cannot be cited for any installation, whether supplying EVs or not.

  • 0

    gkenyon:

    I wonder if Boris was waiting for Amendment 1 before announcing this: https://www.bbc.co.uk/news/science-environment-51366123


    ?




    It` not usual for Boris to act in that way.

    He usually just appears to say something daft whenever it suits.

    Perhaps D Trump is an elder relative of his

  • 0

    gkenyon:




    Somewhere on the planet it is daytime, somewhere it is night time, somewhere it is raining, somewhere it is snowing, somewhere it is sunny, somewhere it is winter, somewhere it is summer.




    Made me think of the Seekers - Morning Town Ride (starting at the bit I time-linked to ... the following verse at 1:24 starts "Somewhere it is night time, somewhere it is day ...").


    Sad, I know ... something my Mum used to sing to me when I was a toddler, and we sang to our kids when they were toddlers ?



    Sadder still Graham, I used to listen to it on radio when it was in the hit parade, I liked the Seekers. Hmm I`m old.

     Every time I drive past that building with your name on it (say 4 or 5 times per year) I will not only have a pic of you in my mind but now know you`re younger than me. A day out from near a hill, to the coast, a haven that`s fair with a lake then onwards to a metal monument that French copied off us sometimes past an Airport that was known not by town name but such likes as Ringway, Speke etc etc.


    American Pie was released after I started serving my time (Apprenticeship not a Jail Sentence)




     

  • 0
    Came across this video showing how N-E voltage can rise with a broken PEN conductor and subsequent disconnection of an EV charger

    https://youtu.be/ZedTmlTLH2w


    F
  • 0
    When there is a broken CNE situation in a three-phase main, the rise of local earth (neutral) potential relative to Earth (the general mass of Earth) depends on the phase unbalance in the system downstream of the break.


    If you have a single-phase supply from a three-phase main, unless you are unfortunate enough to be the last property on the main downstream of the break, your MET voltage to Earth will shift up and down, as loads are turned off and on ... or in some cases, loads become open circuit due to damage by overvoltage. It's therefore likely the voltage will shift every few minutes. Therefore, whilst not an exact science, statistics not being available to determine an "absolute risk", it is highly improbable that a broken CNE conductor event will go unnoticed indefinitely by the device described in 722.411.4.1 (iv). Devices that offer equivalent, or improved, safety to the measures described in 722.411.4.1 (iv), or, where applicable, 722.411.4.1 (iii), are of course permitted by 722.411.4.1 (v).


    Luckily, if you happen to be the last property on the main downstream of the break, the device described in 722.411.4.1 (iv) works just fine.



    A caveat for some of the protective devices, is that they may cease to function correctly in prosumers' installations operating in island mode (where they remain connected to the PME earthing system).
  • 0

    Farmboy:

    Came across this video showing how N-E voltage can rise with a broken PEN conductor and subsequent disconnection of an EV charger

    https://youtu.be/ZedTmlTLH2w


    F




    I've got my worries about using the current through the c.p.c. to trigger a shutdown (>18mA in that example) - how likely is it to false trip in the real world?  I wondering that if the car happens to provide a parallel path to earth say either via wet/muddy/salty tyres or say an open door touching a steel bollard or lamppost - then you'd expect a reasonable amount of PME diverted N currents to flow from the installation/supply via the car's c.p.c. - if the charge point is going to trip out every time that happens they aren't going to be very popular.


        - Andy.

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