Armoured cabling questions

[JohnW2]

And it must also mean that black+blue and grey+blue twin and earth cables are readily available to use on single phase circuits in 3-phase environments.

Again, no. Because who in their right mind would consider using T&E in such environments, assuming that these are not domestic installations?

Do you mean that you would use singles?

In my (domestic) environment, I have a 3-phase supply which feeds (separately) only single phase CUs. If that were in the south of Ireland, would the distribution circuits (to those CUs) then have to use brown, black or grey L conductors, as appropriate? - and, much more to the point, what colour would I have to use for the L conductors in the final circuits originating from those CUs (needless to say, all mine are brown, or black where pre-harmonisation colours survive)

Kind Regards, John

 

[ban-all-sheds]

However, for timer fans and for interlinked smoke detectors I would use a 3C & E for convenience (but only in the north).

"Where more than one conductor in a multi-core cable is fed from the same phase, both shall be identified by the relevant phase colour, using sleeving as needed"

It actually states "using supplementary colour marking" as opposed to "using sleeving", but obviously that does not alter the meaning.

Obviously not. So the meaning remains that where more than one conductor in a multi-core cable is fed from the same phase, both shall be identified by the relevant phase colour, using supplementary colour marking (or sleeving as needed).

In other words, there can be absolutely no doubt that the use of multicore cables with different coloured conductors to carry the same phase is an expected condition, and that it is perfectly allowable as long as the "wrong-colour" cores are marked with the correct colour.

I can see how you might interpret that your way

I can't see that there is any other way to interpret it.

but I will point out that no-one ever uses 3-core for two-way switching like that

If you tell me that, I accept it. But the reason they don't is lack of original thought, not because it's not allowed.

so I certainly wouldn't advise trying it.

Doesn't affect me.

If it did you may rest assured I would use it.

I don't follow. If using singles in containment as you would (should) be there is no issue in using the respective phase colour for the single phase circuits.

So is every single premises in Eire which has a 3-phase supply and some single phase circuits cabled entirely in singles in conduit or trunking?

Even large domestic properties?

Again, no. Because who in their right mind would consider using T&E in such environments, assuming that these are not domestic installations?

But what if they are domestic installations? On the one hand you say that you can't get black+blue and grey+blue twin and earth, on the other you say that Table 51A stipulates that brown is L1, black is L2 and grey is L3. and you certainly don't think RECI, ECSSA or the ESB would take such a liberal view on reidentifying phases as other phases.

 

[JohnW2]

But what if they are domestic installations? On the one hand you say that you can't get black+blue and grey+blue twin and earth, on the other you say that Table 51A stipulates that brown is L1, black is L2 and grey is L3. and you certainly don't think RECI, ECSSA or the ESB would take such a liberal view on reidentifying phases as other phases.

Indeed so. As I wrote:

In my (domestic) environment, I have a 3-phase supply which feeds (separately) only single phase CUs. If that were in the south of Ireland, would the distribution circuits (to those CUs) then have to use brown, black or grey L conductors, as appropriate? - and, much more to the point, what colour would I have to use for the L conductors in the final circuits originating from those CUs (needless to say, all mine are brown, or black where pre-harmonisation colours survive)

Furthermore, in my installation, I wouldn't have a clue as to which is L1, which is L2 and which is L3. In their infinite wisdom, the DNO have identified my phases as red, blue and green and "A", "B" & "C" (and the incoming neutral is identified by red insulation ) !! :

Untitled

• JohnW2
• 13 Aug 2011
• 5

Kind Regards, John

 

[Risteard]

As I pointed out earlier, single phase circuits fed from three-phase dis boards are permitted to be wired in phase colours - not required to be. So in a domestic premises by all means wire them all in brown and blue with twin and skin.

 

[ban-all-sheds]

So in a domestic premises by all means wire them all in brown and blue with twin and skin.

But Table 51A stipulates that brown is L1, black is L2 and grey is L3. Surely RECI, ECSSA or the ESB wouldn't take such a liberal view on reidentifying phases as other phases?

 

[Risteard]

So in a domestic premises by all means wire them all in brown and blue with twin and skin.

But Table 51A stipulates that brown is L1, black is L2 and grey is L3. Surely RECI, ECSSA or the ESB wouldn't take such a liberal view on reidentifying phases as other phases?

It has to be taken in concert with the Rules, obviously. So given that they explicitly suggest that single phase circuits (not three-phase circuits) fed from a three-phase distribution board MAY be wired in phase colours as an alternative to the single phase requirement of brown and blue - and therefore clearly may alternatively all be wired in brown and blue as they are single phase - it is a stupid point you are making.

 

[ban-all-sheds]

Well - if you wish to explore the concept of stupidity, the point I am making is that you can't on the one hand say "by all means wire them all in brown and blue with twin and skin" and on the other say "Table 51A stipulates that brown is L1, black is L2 and grey is L3. I certainly don't think RECI, ECSSA or the ESB would take such a liberal view on reidentifying phases as other phases" - the two positions are inconsistent.



If there are regulations which allow a brown/blue cable to be oversleeved black/blue or grey/blue, and which require such oversleeving in a multicore cable used on one phase, then the regulations also allow the use of brown/black/grey as a 2-way switch strapper provided the black and the grey are oversleeved brown.

 

[Risteard]

Remarking conductors with different colours is not the same thing as legitimately using a particular set of colours, so your point is not relevant or valid.

 

[ban-all-sheds]

Do the Irish wiring regulations allow a black or grey conductor in a multicore cable used in a single phase environment to be oversleeved brown, yes or no?