New EHU Wiring Regulations

Jun 20, 2005
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This months CAMC Mag explains the change. Apparently the EHU must have an interlock to prevent plug insertion and extraction when the socket is live. Thus the MCB is designed to trip every time the plug is extracted. The reason is to avoid arcing and accidental contact with live conductors. I haven’t seen this set up yet.
I imagine the Wardens will be busy flicking switches 😜
 
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Jul 18, 2017
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This months CAMC Mag explains the change. Apparently the EHU must have an interlock to prevent plug insertion and extraction when the socket is live. Thus the MCB is designed to trip every time the plug is extracted. The reason is to avoid arcing and accidental contact with live conductors. I haven’t seen this set up yet.
I imagine the Wardens will be busy flicking switches 😜
Probably only apply to new installations? It will not prevent arcing. On a caravan site the design of the plugs prevents accidental contact unless you insert something conductive to touch live poles.
 
Jun 20, 2005
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Probably only apply to new installations? It will not prevent arcing. On a caravan site the design of the plugs prevents accidental contact unless you insert something conductive to touch live poles.
As far as I know,new installations
 

JTQ

May 7, 2005
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Did not the CMC's twist plug to engage, button to release type bollards do this? Elsewhere, I have met few "users" intended on bollard isolator provisions.
It makes sense insofar as I suspect few users ensure the van/MH's isolator is "off" before plugging the EHU in, therefore, the potential to make and break continuity on the plug/socket's pins.
I am as guilty as many, despite my van's manual telling me to isolate van before connecting or disconnecting the EHU.

Wonder in real life what implications there have been over the decades, though I can see there is a human hazard risk in our practices, which the likes of the clubs have to take onboard and mitigate.
 
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Nov 11, 2009
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Did not the CMC's twist plug to engage, button to release type bollards do this? Elsewhere, I have met few "users" intended on bollard isolator provisions.
It makes sense insofar as I suspect few users ensure the van/MH's isolator is "off" before plugging the EHU in, therefore, the potential to make and break continuity on the plug/socket's pins.

Wonder in real life what implications there have been over the decades, though I can see there is a human hazard risk in our practices, which the likes of the clubs have to take onboard and mitigate.
Prior to my final retirement I established a business division within a Defence consultancy to provide consultancy services in safety and environmental risks. I retired when the group CEO decided it should be launched as a stand alone business. The safety service that we provided was not that associated with the more routine occupational health and safety where some practitioners can be overzealous in their perception of hazards, but do not consider the probability or consequence of encountering a hazard. Neither do they always consider the cost-benefits to mitigate the risk, or to reduce it to a tolerable level. Our approach was aligned with the HSE guidance developed after the Piper Alpha incident, and evolved to develop safety cases for warships, defence systems and infrastructure. For warships some safety cases were retrospective for ships that had been in service for up to 20 years. We used the ALARP principle …..As Low As Reasonably Practicable. Recognising that in defence systems there are many hazards which cannot be removed, so mitigation is necessary. Wikipedia gives a good description of ALARP. I suspect that the CAMC new EHU requirements were driven more by Occupational H&S advisors. But since it is unlikely to be retrospective then the cost-benefit should be positive.

 
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Nov 12, 2021
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It won't stop motorhomers leaving a live socket when they go out for the day!
I've just returned from Old Pastures Park near York. It opened in 2020 and it has EHU breakers which trip when the EHU plug is removed from the socket. Therefore, when you plug in, the circuit isn't live until the breaker switches are flipped up again.
 
Mar 14, 2005
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Its very rare to find revised wiring or appliance regulations are retrospective, so as others have said it will only apply to new or possibly any revisions or repairs to pre existing wiring schemes.

New or revisions to regulations requiring pre existing systems to be modified are only usually made if: failing to do so would render the system illegal, or the probability and risks of an event are both high.
 

Sam Vimes

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Sep 7, 2020
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I've just returned from Old Pastures Park near York. It opened in 2020 and it has EHU breakers which trip when the EHU plug is removed from the socket. Therefore, when you plug in, the circuit isn't live until the breaker switches are flipped up again.
I've also come across this feature which can be slightly annoying as I've found that other users pulling out their plugs e.g a motorhome going out for the day, would also trip mine.
 
Nov 6, 2005
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I've just returned from Old Pastures Park near York. It opened in 2020 and it has EHU breakers which trip when the EHU plug is removed from the socket. Therefore, when you plug in, the circuit isn't live until the breaker switches are flipped up again.
My comment was aimed at those motorhomers who simply unplug their cable from the motorhome and leave it trailing on the ground when they go out for the day - it's probably only a minority but a sizeable one nevertheless.
 
Mar 14, 2005
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We hav ecome across these bollards at Winchester and Carsington Water sites,as were unaware(didnt read instructions) it took us a while to work out, as did others once sorted it wa sall fine
 
Oct 8, 2006
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This is very reminiscent of the Part P regulations that came out in 2005. This was mainly because of 'amateur' wiring in dangerous places such as kitchens and bathrooms. It meant that work in such areas had to be done by qualified/certified electricians, or if done by a non-certified (should that be certificated?? ;)) persons it had to be checked by a qualified person or your local council - at (then) a typical cost of about £400!
The argument was about deaths or injuries caused as above. It transpired that nationally in the previous decade 4 people had died and about 20 been injured by such 'amateur' wiring. I went to a one-day presentation for electricians about the new part and what it involved. I'm sorry to say that I didn't stay as (a) it was all about common sense and (b) IMO was certainly a case of 'jobs for the boys!' (And at that time I was a FIET!)
 
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May 7, 2012
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Sounds over the top to me. Possibly the old twist to insert and remove could be made to do this automatically and re connect when another plug is inserted. As Otherclive says you cannot rule out accidents all together, our safety presentations would quote the guy who failed to do up his shoe laces and tripped up. We could produce a graph that showed how the cost of accidents dropped with the safety spend increasing. Most businesses were interested up to the point the lines crossed and spending on safety cost more than the cost of accidents.
 
Aug 24, 2020
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I met these new hook-ups at Littlehampton CAMC site earlier in the year - I'd never seen one before, but it was the first trip out (no pun intended) in the new-to-us van, so when I plugged in and got no power I was crawling all over the van trying to find what was causing the trip out.

I subsequently discovered that if the trip (on the bollard) looks as if it's in the "half tripped" position, you can't just reset it - if you do it'll just trip again immediately. You have to pull it all the way down, then push it up, and then the breaker will engage.

I don't know if this is going to be a common feature on all of the new design breakers or if Littlehampton had an odd batch, as I haven't stayed at a site with this new type of bollard since.
 
Jun 20, 2005
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According to the CAMC mag the change for new installations arises because of changes in the Electrical wiring regs.
I wonder how many times an MCB can be reset before failing😵‍💫
 
Nov 12, 2021
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My comment was aimed at those motorhomers who simply unplug their cable from the motorhome and leave it trailing on the ground when they go out for the day - it's probably only a minority but a sizeable one nevertheless.
Sorry Roger, I wasn't having a dig. I was just stating that the site we were on had these new breakers. Which in turn, would negate the danger of leaving a live cable lying around because the breakers trips when it's disconnected from either the bollard or the caravan/vehicle.
The breakers can't be reset either if there is nothing connected to the bollard making the setup very safe.

When the site owner was explaining how the breakers work he did say that the regulations now require this type of breaker to be fitted. So, we should expect to see them becoming the norm on new sites.

I've also come across this feature which can be slightly annoying as I've found that other users pulling out their plugs e.g a motorhome going out for the day, would also trip mine.
Interesting that Sam, I wonder if there was an underlying fault with the bollard you were hooked up to because I didn't experience that problem. We had at least four different neighbours who were hooked up to the bollard we were connected to during our stay and it never tripped once.
 
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Jan 3, 2012
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I've just returned from Old Pastures Park near York. It opened in 2020 and it has EHU breakers which trip when the EHU plug is removed from the socket. Therefore, when you plug in, the circuit isn't live until the breaker switches are flipped up again.
Just been looking at that site did you have a nice time the Luxury Glamping looks fab
 
Jun 20, 2005
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I was under the impression the MCB only triggers when the plug is pulled from the EHU not the caravan? All new to me.
 
Nov 12, 2021
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Just been looking at that site did you have a nice time the Luxury Glamping looks fab
No it was absolutely dreadful, don't go!

No, I am joking. To be honest, we booked 12 nights and then extended to 17 when we were there and whats more, we would have stayed even longer but, the weekend was fully booked.
We looked at the two glamping pods on our evening walk around the lake and they look very comfortable and well equipped. The only thing is, you have to park your car by the main house and walk about 200 yards around the lake to the pods. It is a proper, well dressed path though and lit at night.
We saw a couple arriving and Sam, the owner was transporting their luggage for them on a trolley so, your not expected to lug it yourself.
It's a fantastic base to explore York and beyond from.
 
Oct 8, 2006
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It is interesting reading the variation in the 18th Regs relating to caravans and motorhomes. For anyone who understands electrickery you might find this specific section interesting reading: 18th edition IET Regs

The bit that I find strange is that all supplies (i.e. from a pillar) must be protected by a RCD that disconnects both supply lines, L and N. BUT the RCDs fitted in caravans already have such, whereas the IET seem to think that the RCD in a caravan only disconnects the live wire. They refer to this as an RCD but AIUI a single pole current leakage breaker is actually a RCBO albeit it is also a single pole MCB. We are all also familiar with the MCBs in the caravan being dual pole but again this amendment to the Regs suggests that the breakers are expected to be of the domestic single-pole variety.

I am also concerned about the requirement about a supply outlet that cannot be live without a plug inserted. Surely even the insert and twist variety that have been the norm for decades is compliant as you cannot turn the outlet without having something inserted into the socket to turn it and you cannot unplug without pressing the button? If there is someone who is so stupid that they try and bypass this protection then IMO they deserve whatever they get. I suppose unless someone is watching (and recording?) what that person was doing or did before the accident would not be a defence on behalf of the site owner/operator if the result was a prosecution?

I get that horrible feeling that whoever wrote the amendments was neither a caravanner/motorhomer nor have they consulted anyone who is. If it is affecting the IET as much that they cannot even have the section subbed by someone who does know about and understand caravans what hope do we mere mortals have - and I speak - as already noted - as a former FIET!!
 
Mar 14, 2005
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I suspect the regulation has been written as such because they recognise that whilst the site operator is responsible for the site wiring, the cannot control the condition or standard of the wiring in visiting caravans or motorhomes. So the Sites wiring needs to be ultra safe just in case a visitor connects a system which does not use double pole disconnection.

Don't forget the same regulations will apply the static caravans and Holiday homes, which might us an older style domestic consumer unit with only Live disconnect RCD protection.
 
Jan 3, 2012
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No it was absolutely dreadful, don't go!

No, I am joking. To be honest, we booked 12 nights and then extended to 17 when we were there and whats more, we would have stayed even longer but, the weekend was fully booked.
We looked at the two glamping pods on our evening walk around the lake and they look very comfortable and well equipped. The only thing is, you have to park your car by the main house and walk about 200 yards around the lake to the pods. It is a proper, well dressed path though and lit at night.
We saw a couple arriving and Sam, the owner was transporting their luggage for them on a trolley so, your not expected to lug it yourself.
It's a fantastic base to explore York and beyond from.
Thanks for letting me know that be to far for me to walk (y)
 
Aug 24, 2020
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Just spotted something else in the document in Woodentop's link...I know we're only seeing one bit of a bigger document, but in the section relating to the hook-up lead it says

"The means of connecting the caravan to the pitch socket-outlet should be provided with the caravan. This must have a plug at one end complying with BS EN 60309-2, a flexible cable with a continuous length of 25 m (±2 m)."

Does that mean that those of us who carry a shorter mains lead, to use when we're closer to the bollard, won't be able to use it any more?
 

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