O-pen devices, Overvolatge, IET-01, increasing the volatge to mitigate issues !!!!!

Dom said; "Its one of these situations where we are damned if we do damned if we dont"

I imagine that may well have been the state of affairs that afflicted those who were responsible for the regulation, damned if they ignored the risk and damned if they insisted on control measures that would be difficult and costly to implement. Likely they saw a real risk with EVSE on PME supplies that deserved a specific regulation and strained to balance that with the disadvantages of any proffered control measures. Perhaps the cure would turn out worse than the illness.

That seems to be the issue here where the functionality of the EVSE is compromised by the o-pen control measure built into the EVSE by the manufacturer.

I can understand why manufacturers tried to make the solution integral with their equipment as the trade demands a plug and play arrangement. The trade does not want, and, perhaps because of demand, is not capable of providing sufficient numbers of skilled persons who are also capable of providing bespoke solutions to the vexed question of open PEN.  If the roll out of EVSE provision is not to be impeded, that solution has to be packaged by the EVSE manufacturer.

If it turns out that the packaged solution is not fit for purpose then we have a serious problem. It seems that solar pv is expanding and that DNO networks may end up having voltage issues that cause EVSE to drop out, irrespective of the earthing arrangement the EVSE is connected to. Who knows, a doctor or critical care worker finding that their car was not charged because the network voltage slipped out of certain limits may be a greater risk than an open PEN event.

I have no idea of the state of the network in mainland UK. I am told that in most areas here in NI, the network is healthy and an open PEN condition, whilst not impossible, would be unlikely. Certainly, not more than a few miles from me on the other side of the border, in the ROI, the freshly expanded Part 722 of IS10101:2020 + A1 2024 (their equivalent of BS7671) expresses not one jot of concern about open PEN conditions, even though most of the network in the ROI is of a PME-type arrangement.

In other words, like the implementation of the hierarchy of risk control, get rid of the thing that is causing the problem, which might be the regulation itself. 

In terms of how many open PEN accidents are there here on "the mainland", the data is rather thin, but none the less compellnig that it certainly can happen.
some data from a now rather outdated report from 2019 that was on the myenergi website but has now been deleted.



It is also possible that faults that give a neutral voltage rise but occur in combination with other faults, such as transformer failures, and are reported under the other heading as it were.

so, rare, but not impossibly so. What is not clear from such simplified reporting is if each such event enlivens just one house or a whole housing estate, as the risk of the latter is obviously far higher.

For years electrics out doors has moved from away from class 1 to double insulated instead, almost totally for things like lawnmowers and hedge trimmers, and even outside lights and supplies to CCTV cameras, but cars bring it all back, and worse are not really out of reach and often have earthed metalwork in the form of handles and so on.

Mike

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In terms of how many open PEN accidents are there here on "the mainland", the data is rather thin, but none the less compellnig that it certainly can happen.
some data from a now rather outdated report from 2019 that was on the myenergi website but has now been deleted.



It is also possible that faults that give a neutral voltage rise but occur in combination with other faults, such as transformer failures, and are reported under the other heading as it were.

so, rare, but not impossibly so. What is not clear from such simplified reporting is if each such event enlivens just one house or a whole housing estate, as the risk of the latter is obviously far higher.

For years electrics out doors has moved from away from class 1 to double insulated instead, almost totally for things like lawnmowers and hedge trimmers, and even outside lights and supplies to CCTV cameras, but cars bring it all back, and worse are not really out of reach and often have earthed metalwork in the form of handles and so on.

Mike

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Further data from earlier years and some discussion is here 
https://engx.theiet.org/cfs-filesystemfile/__key/communityserver-discussions-components-files/2/PE01417-_2D00_-IET-Electric-Vehicles-Report-_2D00_-Issued.pdf

however it is clear that at the time of that report (2012 and before) DNOs did not all record open neutral events, and the figures from those DNOs that contributed data seem low compared to those in my previous post.
The Authors acknowledge this (my highlighting)
The Electrical Incidents Database (EID) is an HSE database which explicitly records open-circuit neutral failures (as well as other incidents) throughout Great Britain. This database was interrogated and it was found that, in 2011, there were 271 open-circuit
neutral failures nationwide. From Company A and Company B there were 161 such failures in 2011. Given that the data from the two companies should be included in the EID data, it would imply that there were 110 such failures for the rest of the country.
Company A and Company B supply approximately 15% of properties nationwide (obtained from the National Population Database). It would therefore be expected, assuming that the number of open-circuit neutral faults is approximately similar across the country, that there would be significantly more than 110 faults reported for the rest of Great Britain. This therefore implies that there is a significant level of under-reporting in the EID database and the data cannot be used directly.

Make of that what you will - if 2 DNOs covering only 15% of the population appear to have more than 35% of the incidents, are they the 'good DNOs' reporting everything, or  are their bits of the network unusually shonky compared to the rest ?

In any case the fact remains that events do occur, and it may be just a few hundred a year or more like 3 times that really, but there are not as yet any fatalities to report directly attributed to car charging and broken neutral incidents, so its well below the (unofficial) 1 in a  million per year 'action limit' despite the predictions in the report.
Mike.