EV CHARGING EQUIPMENT

You have hit the nail on the head there Graham. In fact there is no completely safe way to charge class 1 electric vehicles when the supply system is TNC-S. The whole system is "unsafe" in all usage once we start on the "what if" scenarios. For every other use we deem the TNC-S system "safe enough" for normal consumers, and the number of accidents is tiny, and usually stems from stupidity of some kind (taking the heater or radio in the bath for example). The current obsession with RCD protection and AFDDs is another part of this attempt to stop any conceivable risk at any cost, something which is  obviously an impossible goal. At the moment there are not many Ecars, so the way to make charging safe is simply to set the goal as making all new ones class 2. They can make RH drive cars, so why not class 2 ones (although this is probably not needed in Japan with 100V nominal mains often less than 90V). Now is the time for leadership, there will be no sales for months so now is the time made available to tweek a bit of electronics in a fairly simple way. In fact for a sensible fee I will do the work for them! Then PROBLEM GONE forever! All over the world, now that really is an improvement in a time of crisis. The remaining older class 1 cars will not present much risk, and nothing needs to be done to existing charging points, it is just that new ones will be simpler and safer in use. We can make virus tests, drugs, ventilators etc very quickly once there is a good reason to do so, there seems to me to be a very good reason to fix EVs. We can also throw 722 away to the annals of history to everyone's great delight.

Sparkingchip:


Then they wonder why EICRs are so expensive.


 Andy Betteridge

Try this site, that includes supposedly registered electrical contractors - how do they do it? 

https://www.localsurveyorsdirect.co.uk/installation-condition-report-survey


Jaymack

Well we could all use isolating transformer and configure the ouput as our own TNS just for the charger

Is this still an evolving field, or have the standards pretty much settled down?


I have a petrol car; there are filling stations everywhere and I know that the nozzle will always fit my tank. I can go to Europe and find exactly the same petrol there. Other people with different cars can do the same.


If there are different standards for the cars, that is something for the manufacturers to sort out. I don't think that we could make current cars obsolete, so there must continue to be backwards compatibility. (If there were not, then people would not risk buying EVs.)


If the PME business just applies here, we have to sort it out, especially since Brexit. It is no use expecting the manufacturers to make UK only models - RHD/LHD is bad enough - thank God that the Japanese drive on the left!


Is the problem BS 7671? For example, were we better off with the 17th+3 liberal approach to domestic EVCPs? What has driven two changes in less than two years - surely not a spate of deaths or near misses?


What a ***'s muddle! I stand by with a spare way in my DB ready for when I can be confident that any EVCP which I might install will remain compliant for more than half a dog watch.

I suspect there is no appetite for that either.


Especially when I did hear on the news today that car sales were down 44% in March compared to last March. I haven't looked to see the breakdown of type.


Regards


BOD

Or you say a car is product, and as there are standards for TVs, table lamps, radios gas bottles etc, then there should be one for cars, and car makers should follow it or take their non compliant product off the shelf.

Of course cars are a product, and there's a whole raft of regulations they have to meet.  Construction and Use Regulations, if nothing else.


The problem comes when nobody works out how these regulations meet up with others, such as the ESQCR.

I think others will argue that a truly top down approach might demand that the requirements for what sort of supply, and the level of design required for it's safety, should be firmly the responsibility of the car designers. 

I.e. force them to think beyond the connector and to shoulder the burden of the risk.


It is then only  necessary for the authors of the various local/ national/regional l wiring standards of which BS7671 is only one,  to include that  method  to get power to the car, and then DNOs,  BNOs and end users to agree to follow it.


Right now it seems that the HSE and the IET have decided that the risk of a class 1 car on a PME supply in the UK is too high,  (and I agree for what it is worth) but it also seems no-one else in the chain of design agrees so right now no organisation wants to invest in any proper engineering to solve the problem.


Or you say a car is product, and as there are standards for TVs, table lamps, radios gas bottles etc, then there should be one for cars, and car makers should follow it or take their non compliant product off the shelf.

I suspect there is no appetite for that either.

I think the top down bit is very good. 


The standards for EV charging are set out in BS 7671. The IET have also published a Code of Practice for EV charging installations.


The information is there for designers, installers and inspectors. 


What is missing is for people involved in the installation process to keep up to date by doing some CPD and then complying with the standards. There is a load of information on the internet or when they start again they can come along to the Elex shows and sit in on the free seminars. If they need further information they can speak directly to the IET representatives on their stand, NAPIT and the equipment manufacturers.


You said, " if you write down the list of requirements the “EV charging station” with its single pole RCBO with type AC doesn’t tick as many boxes as the new version of the RCD sockets". What were you reading for you to say that?