External cabling and the issues with EV.

You have eloquently cited the reasons it wouldn't be a good idea to run along a fence etc. - I guess it depends on how secure the fence in question is (or will remains). It also depends on where you live - in my area, we have regular gale-force winds, even for quite a distance inland (because it's flat), so many standard wooden fences are not suitable ... but it depends on the structure.

Nothing wrong, however, with securely running SWA along more rigid structures, such as a wall.

Dom said:

With Ev and the subsequent demand I feel our industry desperately needs to look at new containment solutions or pursue solutions in fulfilling a clients ask. Safely of course!!!

There are two sides to this story ... wishful thinking that an EV charging point can be purchased and installed in most installations for < £500 could be said to be one of the issues. It's long been known that major infrastructure changes would be required for EV charging, and that isn't limited to the distribution network. That also ignores installations that may require other enabling work to be carried out, and the debacle over earthing issues ... not limited to the charging point itself, but say you already have a separate garage on TT, there are still multiple earthing systems in the installation, and therefore still potentially requires a simultaneous contact assessment.

Couldn't make it up, could you?

Well in practice, the cheap thing to do will be to put the charger on, or even inside, the main building and extend the flexible cable the last 10/15m, consider it consumable part, and replace it when it gets damaged.

In some ways, as well as meeting the £500 budget,  this is not as horrible as it sounds. 

Firstly the cable to the car  is safer and better protected electrically speaking than the one between the consumer unit and the charger, being interlocked with the car and the earth verification  loop,  and even it it wasn't it is dead most of the time, so reducing the chances of being damaged and left live while no-one is about to see it, and also reducing the electricity theft risk. It could even be coiled away when not in use, but probably won't be, but at least it could be coiled up when the fence is blown down, unlike a permanent installation....

Mike.

Thank you for these points some excellent ones to consider (simultaneous contact) - which I will. Can I ask you your thoughts on new cable containment systems to support the evolution of EV in respects to a clients ask and ease of install. Do you think there will be a need for such a thing moving forward? 

In respects to your point around the security of fences I would deem the structures with concrete bases to be of solid construction with due diligence taken to fix to the concrete pillars only, one must be mindful of support distances of cables in this instance.

Would it be fair to use engineer judgement in fitting to a fence that is mechanically sound. Is this something that we should be looking at within the next amendment? Or is it prudent to leave as is, part of me believes these issues should be discussed and the discussion should work around solutions, there has never been more of a demand for outside cabling as there is to day. If the proper questions are asked and discussed then we may well be able to make a decision that is in line with the professional and safe standards BS7671 has provided us with for decades.

Thanks, 

Dominic.

Good morning Mike.

The point around the charging cable got me thinking in respects to a possible - retraction system for the cable. This would need to be designed with a limit on the cable charging while any of it is still coiled but it is still a very good idea around using the lead.

Thanks Mike. 

you might need a slightly tougher lead for semi-permanent exposure to the outside world - if it might get run over for example, but a longer 'hose-like' lead  also solves the problem of shared parking and not always being in the same one of half a dozen adjacent  bays. An all cores extension protected with  something like SY braid and a break detector would probably do.

There are ways of coiling and retracting flexible cables that allow free airflow between the turns, effectively skeleton reels with grooved cable guides, to give an open winding  and in extremis these can be air blown or even liquid cooled.

(You can also do clever things to the cable - I have worked on some funny stuff over the years including one that had provision for running  cooling water tubes within the (rather hot) cable construction, so I tend not to be so phased by things that others look at askance)

Mike

Fantastic Mike - thanks again for this insight.

mapj1 said:

extend the flexible cable the last 10/15m, consider it consumable part, and replace it when it gets damaged.

So, yes a technically feasible solution, but this approach is deprecated in guidance, because of:

• trip hazards (sectors like postal & delivery services, sometimes accessing properties in poor lighting conditions in the dark have reported issues)
• accessibility issues, and making access more difficult for wheelchair users etc

In workplaces, such issues are required to be considered for CDM.

I'm assuming it follows the route along the fence or whatever that the fixed wiring would, and not violin string tight diagonally across the path - though I agree if you do this method that allows that to be done.

But In reality at the shallow end where there is no charger at all, I expect to see extension leads out of upstairs windows of terraced houses as a pragmatic if rather ugly way to cross the pavement. After all washing lines have been doing that sort of thing for years in some cities. (probably not the nicer ones down south though ) and where it happens it is not always peaceful co-operation - as this tale of argument and sawn off washing line hooks tells.

Mike.

PS Leeds quite recently

Great story Mike. I couldn't help but look on google streetview of the back streets of Skipton, yes the washing lines are still there:- https://www.google.com/maps/@53.9586596,-2.0351512,3a,75y,13.81h,93.62t/data=!3m6!1e1!3m4!1sd59uuEhuYYyXDDaZervfTw!2e0!7i13312!8i6656

Back to the original question, have you considered putting the cable in unistrut? - self supporting, into/onto the ground if necessary, can then provide a mounting for the "charger". In that case you will probably end up holding up the fence :-). In industry it is used quite a lot for single cable runs that are awkward or small spans, just put the SWA inside - looks neat. Don't know about domestic use though.

I seem to remember there are very strict limits on the cable length between car and charger?

Very interesting point there Roger re the uni strut - I have mounted chargers on strut before but the cable was ran in ducting.