Dangerous reverse polarity on meter tails

[sidekick]

I have today come accross my first polarity problem.
while checking a socket i found it was showing reverse polarity with L and N.
After checkig behind the socket and all other sockets on the same ring all were correctly wired.
I checked the polarity of L and N at the consumer unit and although also wired correctly this also showed reverse polarity. The job was in one of three flats so were sub mains from the basement where the meters are. In the basement each flat has its own main fused switch from its own meter. On checking this main fuse switch it also showed reverse polarity but was correctly wired.
When i say correctly wired in all cases i mean all Neutrals were black sheathed and all line conductors red sheathed.
However, the tails from the meter to the main fused switch pass via a 100A connector block. In this block both black neutral conductors correctly go into th front connector and both line red conductors go into the rear connector block.
I am assuming the problem is then at the exit from the meter where Line and Neutral must incorrectly wired.
The only identification at the meter is the colour of the sheath so I can do no other check.

Leaving the meter I believe the Neutrals are always side by side in the middle and the two lines are on either side ( L-N-N-L ) but in this case they are ( L-N-L-N).
Is this just a straight case of contacting the supplier to rectify a dangerous situation asap or am I missing something?

 

[tony mc]

If you have tested at the CU and the supply coming into it is reversed you need to isolate the main switch and contact the DNO immediately and have it rectified..

Its your instuments that you have to take note of not the colour of the conductors.

I take it that you are testing with an approved voltage indicator etc.

 

[Geoffsd]

You have done all the testing but to verify can you not switch off switch-fuse and test which tail has voltage to earth and which has continuity?

Or am I missing something?

 

[Knobhead]

As Tony MC said, get it isolated ASAP and contact the DNO. I think you will get a pretty rapid response.

 

[bluestar]

pull the cut out fuse take the meter cover off on the back of the cover will be a wiring diagram and most likely it will be l n n l job done

 

[grimysparks80]

Im all for taking ou the main fuse if needed but would be very reluctant to cut seals on the meter as ive heard the DNO take a very dim veiw of that.

 

[bluestar]

there`s not a spark on here who hasn`t cut the seals off and whos to say you cut it off

 

[Richard]

A bloke I worl with has very nearly been killed because of exactly what you describe. Isolate and notify DNO ASAP. They'll be there sharpish i'm sure!

 

[grimysparks80]

there`s not a spark on here who hasn`t cut the seals off and whos to say you cut it off

True enough. Am just reluctant to advise anyone else to do it.

 

[Knobhead]

Near 24hrs later and have you done anything?
If anything goes wrong your necks on the line as well as the DNO's. If you know of a dangerous situation and do nothing your equally as liable as the fool who wired it in the first place.

 

[nikmet]

pull the cut out fuse take the meter cover off on the back of the cover will be a wiring diagram and most likely it will be l n n l job done

Why would you WANT to do this??, Make it safe (isolate lock off main switch, then call DNO) they will class this as a high priority and will be out VERY quickly, in my experience they attend dangerous situations often within an hour. Personally I Never cut meter seals as thier is never a need too, leave that for the DNO

 

[bluestar]

there are sparks or people who have near misses every day ,its just a fuse
i replace fuses every day sometimes under load, most times off load most fuses blow due to a fault condition there is not one here just a polarity reversal
iv`e been involved in cu changes for councils and we always pulled our own fuses iv`e also had my apprentice wire from the meter to cu exactly the same way as this resulting in the smoke detector blowing up but you learn to get on with it
you cant isolate a customers premises then wait for dno to come out
your a spark get on with it

 

[dickllewellyn]

there are sparks or people who have near misses every day ,its just a fuse
i replace fuses every day sometimes under load, most times off load most fuses blow due to a fault condition there is not one here just a polarity reversal
iv`e been involved in cu changes for councils and we always pulled our own fuses iv`e also had my apprentice wire from the meter to cu exactly the same way as this resulting in the smoke detector blowing up but you learn to get on with it
you cant isolate a customers premises then wait for dno to come out
your a spark get on with it

Being a spark is one thing, breaking the law and working outside the scope of HASAWA is another. How do you fancy the fraud squad knocking on your door because meter seals have been cut? It can happen, and it's up to you to prove. If I was passing your house and decided a tree in your garden looked like it would fall down, would you rather I took it upon myself and cut it down, or would you rather I contact you (the owner) with my concerns?

 

[bluestar]

well do what you feel but dont close my road off and isolate my house !!!!!

 

[mogga]

there`s not a spark on here who hasn`t cut the seals off and whos to say you cut it off

I BEG YOUR PARDON Sorry I have cut seals on main fuses but with AUTHORITY AND TRAINING I Never advise this option specialy NOT on the forum as
1 you dont know how competant the person your advising is
2 you have no knowlage about the cable head type
3 you cant see the condition of head bakalite broken ect ect ect FFS I WISH GUYS WOULD STOP saying PULL IT willy nilly

 

[1shortcircuit]

bluestar, how you conduct your business is entirely up to you my friend but remember that this is a public forum that a lot of inexperienced members/onlookers have access to. I personally don't think ANYONE should be advising to tamper with meter seals, as said though, if you do it then that is your problem to deal with if it ever goes belly up

Pulling a fuse is not allowed but many do it in order to achieve safe isolation. By calling the DNO it means that they can rectify the problem and even investigate who how or why this was done and possibly check other properties - doubtful I know but it's still a possibility.

:d

:thumbsup

 

[1shortcircuit]

I BEG YOUR PARDON Sorry I have cut seals on main fuses but with AUTHORITY AND TRAINING I Never advise this option specialy NOT on the forum as
1 you dont know how competant the person your advising is
2 you have no knowlage about the cable head type
3 you cant see the condition of head bakalite broken ect ect ect FFS I WISH GUYS WOULD STOP saying PULL IT willy nilly

Quicker fingers :cool

 

[nikmet]

there are sparks or people who have near misses every day ,its just a fuse
i replace fuses every day sometimes under load, most times off load most fuses blow due to a fault condition there is not one here just a polarity reversal
iv`e been involved in cu changes for councils and we always pulled our own fuses iv`e also had my apprentice wire from the meter to cu exactly the same way as this resulting in the smoke detector blowing up but you learn to get on with it
you cant isolate a customers premises then wait for dno to come out
your a spark get on with it

Why cant you?............its the correct and sensible thing to do

 

[hoover]

I wonder how the guy got on with the reverse polarity and dno?

 

[Knobhead]

I wonder how the guy got on with the reverse polarity and dno?

Would be interesting to know.

Just hope Mrs. X didn’t get a neutral / earth fault on her iron in the mean time, 100A cut out fuse backing up a bit of flex doesn’t bear thinking about!

 

[bluestar]

yes would be intrested to see what the dno did
last time i used them they left the premises with the same dangerous fault as they were called out for as he told me" my responsibility stops at the cut out "

 

[SirKit Breaker]

The last time i came across this a few years ago i banged my head against a wall for a while on the phone to the meter fitting company, whilst they tried to decide who should come and sort it out as it had only been fitted about 3 weeks earlier. So i swapped the tails over myself at the meter to make it all safe, and balls to the DNO etc. I would rather take my chance in court for cutting seals on a dangerous install and making it safe, over leaving it as it was and getting the blame for death or injury. It was also LNLN instead of LNNL.

Cheers..........Howard

 

[Geoffsd]

There is a switch-fuse in the installation in question and I have been wondering why the out-going tails were not swapped and marked, at least temporarily.

 

[telectrix]

There is a switch-fuse in the installation in question and I have been wondering why the out-going tails were not swapped and marked, at least temporarily.

but , if that were to be done, then DNO or supplier came and put the original fault right, the installation would then be back to reverse polarity! i'm with sir kit on this cut and be damned. safety of lives overrides petty rules.

 

[nikmet]

How can peoples lives be at risk , and how can the electrician who discovers this fault be blamed for death or injury if they isolate the installation and lock it off? A call to arrange for a DNO repair and all is well again.

 

[Geoffsd]

Fair enough, tel, but I assumed spark would be there when DNO/supplier came.

 

[Mark F]

How can peoples lives be at risk , and how can the electrician who discovers this fault be blamed for death or injury if they isolate the installation and lock it off? A call to arrange for a DNO repair and all is well again.

This is what i would do too, maybe inconveniant for the customer, but it's the safest, with no comebacks, and the inconvenience for the customer should be sorted by the DNO.

 

[Knobhead]

I got caught out removing meter seals years ago by the North Western EB as it was then. Just got a ticking off by a senior engineer. Mind you he was trying to get his head round a bigger problem at the time.

 

[nikmet]

I think the issue that seems to be being discussed here, with a differance of opinion, is more to do with customer inconvienience and very little if anything to do with safety?

 

[telectrix]

I think the issue that seems to be being discussed here, with a differance of opinion, is more to do with customer inconvienience and very little if anything to do with safety?

totally agree, but as said on a previous post, since the de-nationalisation, DNO's responsibility ends at the cut-out, or maybe the supply side of the meter. it's then the supplier's responsibility. known in the trade as "buck-passing". IF DNO or whoever will come out in a resonable space of time and correct the fault, fair enough, but you can't expect the customer to accept a freezer full of rotten food as an "inconvenience".

 

[shorty]

I think the issue that seems to be being discussed here, with a differance of opinion, is more to do with customer inconvienience and very little if anything to do with safety?

I agree we all seem to have got off topic. The overriding issue is safety to people and the safest thing to do for everyone is isolated supply using main switch, lock it off and report to supply authority. This leaves it all above board.

Yes it inconveniences the customer but I think the customer would rather be safe than risk personal injury.

 

[sidekick]

Thank you to all on this thread for the advice. Some good, some not so sure.
With so much interest I think its only fair to let you all know what I did etc.

After talking to the customer and explaining how dangerous this was, she was very keen for me to advise and get the fault corrected in the best way possible.
I firstly isolated the flat with the switch fuse in the basement and locked off. I then contacted DNO who were very helpful and promised to get an engineer to the premises as soon as one was available in the area.
The customer was happy in the flat with just a gas cooker and a box of matches and some candles for the time being. Unfortunately, it turned out to be about 24 hours.
DNO called in and confirmed tails were reversed and corrected the fault with a strong apology and no charge.
Flat now safe and power restored, the customer was very grateful and thanked me for my professionalism.

At the end of the day I think safety especially the customers is always the priority regardless of any legal actions we need to take to achieve it. If this is not the case, with anyone either leaving a dangerous situation or taking unauthorized measures just to keep a customer happy then I would think that would not be the correct, the professional, the safe, the legal or the sensible way to do things.

Thanks again.

 

[Knobhead]

Thanks for letting us know the outcome. BUT 24hrs for the DNO!

 

[gbert]

in my new house when NIE northern ireland electricity connected up the meter, though i had clearly marked live and neutral on the tails, they connected live into neutral and visa versa. they had the cheek to tell me i had a wiring problem. i had the tails wired into two iscos and was able to fix it myself but there you have it mistakes are made

 

[sidekick]

Thanks for letting us know the outcome. BUT 24hrs for the DNO!

Yes 24 hrs. That was too long for something so dangerous and inconvenient for the customer. But it was down to the customer not home or able to allow access sooner so not strictly there fault for such a delay.

 

[sidekick]

in my new house when NIE northern ireland electricity connected up the meter, though i had clearly marked live and neutral on the tails, they connected live into neutral and visa versa. they had the cheek to tell me i had a wiring problem. i had the tails wired into two iscos and was able to fix it myself but there you have it mistakes are made

Yep and its mistakes like that that give good reason for the polarity checks which most of the time just point out the obvious. As we both now know it is not always obvious.

 

[Dark Derek]

I wonder how the guy got on with the reverse polarity and dno?

I won't give the whole method but this was almost certainly a case of fraudulent extraction of energy by a previous resident.

 

[James]

I won't give the whole method but this was almost certainly a case of fraudulent extraction of energy by a previous resident.

This is an old thread that probably has been resolved by now.
however it did get me thinking, it may be possible to extract electricity through a meter if the polarity is reversed in the right place but would require a separate earth connection and some serious rewiring.
send me a sketch via pm and we will see if we are on the same thread.