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!