Poll: Over-sleeving Harmonised 3C+E Cable

When using harmonised colours 3C+E for L, S/L and N, is black or grey preferred as neutral?


  • Total voters
    28
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I just use the logic of the pre harmonised colours.

brown or red permanent live
black or yellow switched live
blue or grey neutral.

It seems the most logical order to me.
 
There are two schools of throught.

Grey neutral maintains the same old-->new mapping for both single and three phase applications.

Black neutral is less likely to be surprising to diyers who grew up with red/black.

IIRC when the new colours were introduced the NICEIC pushed the former approach making it the most common among professional electricians.
 
There is another school of thought as well, namely -







It doesn't matter which you use as long as they are identified.

Trying to impose spurious rules is pointless as you will NEVER know what the previous electrician did.
 
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I think in order to get a definitive result, your poll would better off discarding the last two options, as they make people sit on the fence.
 
I just use the logic of the pre harmonised colours.
brown or red permanent live; black or yellow switched live; blue or grey neutral.
It seems the most logical order to me.
For what it's worth, that's also what I do. However, whilst that also seems 'logical' to me, I accept that others have arguments as to why alternative strategies are logical. I certainly always try vto maintain consistency within a given installation.

Kind Regards, John
 
That wouldn't be a difinitive result.

I know you disagree, Sparkwright, but there is no definitive answer because the neutral colur is blue.
 
There is another school of thought as well, namely - It doesn't matter which you use as long as they are identified.
As I wrote to you in the other thread, I agree.
Trying to impose spurious rules is pointless as you will NEVER know what the previous electrician did.
That's true - and, in any event, we are not talking about 'rules', only 'conventions'.

Kind Regards, John
 
I think in order to get a definitive result, your poll would better off discarding the last two options, as they make people sit on the fence.
I disagree, since it is quite possible that the 'definitive result' (i.e. a true reflection of what people think/do) might be one of those last two options. I only split them because EFLI had suggested that black was logical if it was a predominantly red/black installation, hence with most of the neutrals being black.

Kind Regards, John
 
There are two schools of throught. Grey neutral maintains the same old-->new mapping for both single and three phase applications. Black neutral is less likely to be surprising to diyers who grew up with red/black.
Indeed - that's why there probably is not a consensus view.
IIRC when the new colours were introduced the NICEIC pushed the former approach making it the most common among professional electricians.
As I said in the other thread, I suspected that NICIEC might have been behind it. Knowing how they often work, I'm surprised they did not make it a 'rulke' (at elast for their members)!

Kind Regards, John
 
Yes but you wouldn't specifically choose black on the new cable just because the old non-harmonised wiring naturally had black neutrals.

Non-harmonised and harmonised are different systems altogether.
 
Yes but you wouldn't specifically choose black on the new cable just because the old non-harmonised wiring naturally had black neutrals.
I'm not sure what that is a response to, but isn't that precisely the reason why people who deliberately use (harmonised) black do so?

Kind Regards, John
 
I'm not sure what that is a response to, but isn't that precisely the reason why people who deliberately use (harmonised) black do so?

Kind Regards, John

Yes, they do - out of ignorance.
They misguidedly think because black always used to be neutral, then they should use the new harmonised black as neutral.

But the two systems are different.

We know that
Red = brown
Black = blue.

We know that
Red = brown
Yellow = black
Blue = grey
Black = blue,
typically 3 phase.

We know that the structure of a 3 core and earth cable is
Red = brown
Yellow = black
Bare earth = bare earth
Blue = grey.

We know that the PREFERRED choice for neutral on a non-harmonised 3 core and earth cable was blue.

Since the heading of this poll is simply asking for the PREFERRED, not compulsory, colour of a neutral on a harmonised 3 core+e, I would urge anyone who voted the third or fourth option to change their vote, and vote for which colour they choose to use, based on logic and personal preference.
 
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We discussed this in another thread, and I think this was agreed.

You only have to look at installations done before 2004 to know this is a fact, on a 3 core+e cable blue would be used as neutral.

It seems even silly people would never use the yellow as a neutral.

More than 99% of the time, blue would be used, I would estimate. I don't know why. But it was always blue.
 
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