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Hi guys,
Just want some advice on codings for an EICR im doing at a factory.
1-they have wired a radial circuit feeding several sockets in singles using blue singles as a live conductor and black as a neutral.
2-they have 3x ring main mains on 32amp RCBOs type C and all zs values are higher than the permitted zs. With this having RCD protection are you ok to rely on this for fault protection.

Your help is appreciated.
 
Is this a pre-harmonisation installation?
And is the socket radial connected to L3?
If the answer to both is yes then no code, blue was a phase colour in those days and it used to be ok to wire SP circuits in their relative phase colour
 
Is this a pre-harmonisation installation?
And is the socket radial connected to L3?
If the answer to both is yes then no code, blue was a phase colour in those days and it used to be ok to wire SP circuits in their relative phase colour
Seen this a lot especially on lighting split over 3 phases, can be rather confusing when making alterations or additions.
 
An RCD to bs 61009-1 can be used to comply with disconnection times on a TN system for a final circuit not exceeding 32a. 411.4.9
No code if the measured Zs does not exceed the values in table 41.5.
 
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Should have stuck with good old reliable Red Yellow Blue with Black for neutral,
Question wouldn't even need to be asked.
And under poor light conditions much easier to identify than browns blacks and grey's
Ok I know, I'll get off me box !!
 
I can see where your coming from davesparks but i have been doing EICRs for a while and i like to think i am pretty thorough. I do know that blue is a phase colour obviously but its the first time i have come across using it on a single phase circuit and it does make sense now you have said it,but if im unsure about something id rather ask so i can learn rather than just making a judgement myself and not being sure.
 
Are you sure you should be carrying out EICRs if you don't know that a blue cable connected to the blue phase is acceptable?

It has been unacceptable under BS 7671 for quite a number of years to wire single phase circuits in phase colours. (Other national standards do still permit this arrangement.)

With black becoming a phase and blue becoming neutral it's certainly conceivable that this arrangement could lead to confusion. Therefore it's up to the inspector to decide whether there is a safety issue, and I doubt it is quite as clear cut as some are making out.

Just because something was permissible when it was installed does not necessarily imply that it is considered safe today.
 
It has been unacceptable under BS 7671 for quite a number of years to wire single phase circuits in phase colours. (Other national standards do still permit this arrangement.)

With black becoming a phase and blue becoming neutral it's certainly conceivable that this arrangement could lead to confusion. Therefore it's up to the inspector to decide whether there is a safety issue, and I doubt it is quite as clear cut as some are making out.

Just because something was permissible when it was installed does not necessarily imply that it is considered safe today.

Then you might as well fail every installation with RWB and RYB coloured conductors, and all the solid green since there is a reg specifically forbidding the use of green.
 
If anything about this is unsafe, its the ****s that sat around a table deciding to change perfectly acceptable and in my humble opinion far easier to identify RYB colors in the first place.
I can remember most sparks thinking it was ridiculous at the time, but who listens to us !!
We are just the men in the field, going over the trenches when the command is given.
 
It has been unacceptable under BS 7671 for quite a number of years to wire single phase circuits in phase colours. (Other national standards do still permit this arrangement.)

With black becoming a phase and blue becoming neutral it's certainly conceivable that this arrangement could lead to confusion. Therefore it's up to the inspector to decide whether there is a safety issue, and I doubt it is quite as clear cut as some are making out.

Just because something was permissible when it was installed does not necessarily imply that it is considered safe today.

Had exactly this issue in a school. All the single phase circuits are wired in R/Y/B phase colours. My view is that anyone working on a 230v circuit in a non domestic installation should be competant enough to correctly identify conductors. Only when the incompetant become involved does it go pear shaped. In this particular school I came across a number of minor additions installed by the caretaker....(yes,really!!)...in which he'd wrongly connected blue as N and black as L.
Proves two points.
1. The unbelievable daftness of having the colours blue and black which could be either phase or neutral.
2. Caretakers in school should stick to pushing brooms.
 
Then you might as well fail every installation with RWB and RYB coloured conductors, and all the solid green since there is a reg specifically forbidding the use of green.

LOL. I'm not sure how you can compare solid green cpcs with the use of blue and black conductors, which as I pointed out might mean phase L3 and neutral in pre-harmonised colours, or alternatively it could mean neutral and phase L2 in harmonised colours. Therefore it certainly could be said to be confusing unless there were alphanumeric markings at the terminations!
 
LOL. I'm not sure how you can compare solid green cpcs with the use of blue and black conductors, which as I pointed out might mean phase L3 and neutral in pre-harmonised colours, or alternatively it could mean neutral and phase L2 in harmonised colours. Therefore it certainly could be said to be confusing unless there were alphanumeric markings at the terminations!

They both complied with the regulations at the time, they both present no danger to anyone competant to be working on it.
 
Incidentally, further investigation appears to suggest that the wiring of final circuits in phase colours has been prohibited by the IEE Wiring Regulations since at least the 12th Edition.

See IET Forums - Conductor Identification
 
risteard the regs are not retrospective

Firstly, as I have pointed out if this has been installed since at least the 12th Edition then it did not comply. Secondly, it is overly simplistic to state that "the Regs are not retrospective."

What the HSE actually state is that an installation designed and constructed to an earlier Edition of the Regulations does not NECESSARILY imply that the installation is unsafe. Ergo, it also does not necessarily imply that it is safe.
 
This is getting silly,

The line and neutral are wired in legitimate colours from the pre-harmonisation era. any competent person will recognise these colours and will carry out safe isolation and will carry out testing prior to switching on after any alterations.
 
Red, yellow and blue were the line colours of the time, black was the neutral. Any competent person encountering a SP circuit wired in blue and black in a RYB installation will know what is going on.

I know. But only red and black was permitted for a single phase final circuit, so blue and black was not a permitted arrangement.
 
I know. But only red and black was permitted for a single phase final circuit, so blue and black was not a permitted arrangement.
where does it say it is not permitted?

its common to find multiple phases at some switches with different colours to identity them.

where does it say it needs to be red?

you can use any colour as long as it isnt g+y
 
where does it say it is not permitted?

its common to find multiple phases at some switches with different colours to identity them.

where does it say it needs to be red?

you can use any colour as long as it isnt g+y

Currently it says it in the 17th edition, prior to that it was the 16th, I don't have a 15th to check and I'll maybe have a look in my earlier regs books later.
 
where does it say it is not permitted?

its common to find multiple phases at some switches with different colours to identity them.

where does it say it needs to be red?

you can use any colour as long as it isnt g+y

Before the 16th Edition it was permitted on the SUPPLY side of a three-phase distribution board, i.e. it was prohibited for final circuits fed from it. And as I said, every Edition since at least the 12th Edition stated this before the practice was prohibited for distribution circuits also.
 
Before the 16th Edition it was permitted on the SUPPLY side of a three-phase distribution board, i.e. it was prohibited for final circuits fed from it. And as I said, every Edition since at least the 12th Edition stated this before the practice was prohibited for distribution circuits also.
which reg, im curious and would like to have a look

i dont recall seeing it in bs7671
 
Haven't got the book near me but would it be around table 51 and 514 reg?
put a sticker onto 514.14.1 and it complies so no code

nothing wrong with using black/grey in single phase.

it is good practise as it shows it is fed from L2/L3 from a TPN supply


if you use brown on a supply fed from the black phase technically its wrong because you are saying it is on L1 but its fed from L2


nothing says you must use brown for single just you must comply with 514.4.

which says L2 is black.

so if its fed from L2 you should feed it with black and blue for single phase
 
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put a sticker onto 514.14.1 and it complies so no code

I don't have the book on me at present, but I can absolutely assure you that it is not permitted to wire a single phase circuit other than in brown and blue. (You will note that it states for single phase the colours are brown and blue.)

A single phase circuit fed from a three-phase distribution board is still a single phase circuit, and therefore is not exempt from the Regulation.
 
from memory i seem to recall wiring final circuits in phase colours around 90/ 91 ish.
don't see the issue here tbh. its to previous set of regs.
note it and move on to the next job.
the only problem i came across is lads getting yellow phase conductors mixed up with g/y ....with predictable results.
 
from memory i seem to recall wiring final circuits in phase colours around 90/ 91 ish.
don't see the issue here tbh. its to previous set of regs.

The point is that whilst it was often done it was never actually permitted. So it wasn't to a previous set of Regs, unless the 11th Edition or earlier permitted it.
 
The point is that whilst it was often done it was never actually permitted. So it wasn't to a previous set of Regs, unless the 11th Edition or earlier permitted it.
Whilst it might not have been permitted in the regs, IMHO it was an instance where common sense bettered the regs. To have different phase colours at a bank of switches was a damn good idea. Unfortunately, since the ill thought out harmonisation, this could cause a lot of confusion.
 
Unfortunately, since the ill thought out harmonisation, this could cause a lot of confusion.

Which comes to my initial point, which was that (irrespective of whether the arrangement was permitted or not (which it wasn't)), it most certainly could lead to confusion and therefore give rise to danger.
 
The use of phase designated colors on single phase final circuits did take place and often was part of a specification designed by electrical consulting companies.
Its pointless burying heads in regs books when these installs are out there, and have been in use for many years.
Personally I would recommend mixed wiring notices for those installs so as to help clear up confusion.
Confusion that has been generated by changing the colors in the first place.
Whats the saying "For the instruction of fools and guidance of wise men". something like that !!
 
I don't have the book on me at present, but I can absolutely assure you that it is not permitted to wire a single phase circuit other than in brown and blue. (You will note that it states for single phase the colours are brown and blue.)

A single phase circuit fed from a three-phase distribution board is still a single phase circuit, and therefore is not exempt from the Regulation.
it actually states you should use the colour for the designation.

if its fed from a tpn board and your wiring in brown's you are wrong eith having browns fed from L2,L3

you should be flagging them in the apropriate phase colours.


its 230 between any phase and neutrel/earth so any of the three phases is fine.


if you are only wiring single phase items to L1 brown how are you balancing the load and complying by flagging it correctly?
 
it actually states you should use the colour for the designation.

if its fed from a tpn board and your wiring in brown's you are wrong eith having browns fed from L2,L3

you should be flagging them in the apropriate phase colours.

You shouldn't, because that is not permitted. A THREE-PHASE final circuit will be wired in phase colours. A SINGLE PHASE final circuit MUST be wired in brown and blue, and the fact that it is fed from a three phase dis board DOES NOT CHANGE THAT FACT.

This is stated EXPLICITLY in BS 7671.
 
You shouldn't, because that is not permitted. A THREE-PHASE final circuit will be wired in phase colours. A SINGLE PHASE final circuit MUST be wired in brown and blue, and the fact that it is fed from a three phase dis board DOES NOT CHANGE THAT FACT.

This is stated EXPLICITLY in BS 7671.
WHERE? it says for single phase brown and blue but doesnt state not to use black or grey.

show me a reg, it isnt dangerous and not against a reg it is just a colour.


the reg i posted earlier says things fed from L2 are black and fed from L3 are grey.

if it was a single phase supply then i would agree with you and it should be brown but if it is from a tpn supply on a phase other than L1 it should be the revelent colour
 
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WHERE? it says for single phase brown and blue but doesnt state not to use black or grey.

Right there. For single phase use brown and blue, ergo DO NOT USE black or grey.

That's like saying it says for L2 use black but does not state "do not use cyan".
 
Right there. For single phase use brown and blue, ergo DO NOT USE black or grey.

That's like saying it says for L2 use black but does not state "do not use cyan".
the only colour it says must only be used for that purpose is g+y and only solid green is not allowed to be used

in other words its fine and not against the regs
 
the only colour it says must only be used for that purpose is g+y and only solid green is not allowed to be used

in other words its fine and not against the regs

You can think what you like but it most certainly is against BS 7671. If it was a job I was responsible for I would make whoever did it rewire it, and they wouldn't have a leg to stand on.

It's not that I have any problem with the practice per se, as other standards I work to regularly permit it and I do it then, but if it is a job within the remit of BS 7671 then it is not - nor has it ever been - permitted.
 
You can think what you like but it most certainly is against BS 7671. If it was a job I was responsible for I would make whoever did it rewire it, and they wouldn't have a leg to stand on.

It's not that I have any problem with the practice per se, as other standards I work to regularly permit it and I do it then, but if it is a job within the remit of BS 7671 then it is not - nor has it ever been - permitted.
you are talking bollox, if it is against bs7671 then why are you doing it. the 7671 is a guide to the eawr etc and if it is against that then you are breaking the law.

it is not against 7671 as there is no reg saying it is not allowed or otherwise


unless the person doing the work was working directly for you or you were the main contractor then you could have it done anyway you like but i would like to see you try to get them to do it if its not in the spec after its been done
 
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