Brown, Blue, Black and G/Y flex?

[SUNRAY]

So lets look at the basics of multicore colours, harmonisation and phase colours etc
First I'll ask the question: What is harmonisation?
Second question: Who with?

UK flex was red, black, green (and I have come across red, black, green/yellow) then in between black and green was added combinations of yellow, blue, orange, grey & brown. (I manufactured Disco kit and clearly recall red, black, yellow, blue, orange or grey & green). Then the explosion of variations in the early 70's and I found i was using 7 core: 3xbrown, blue, purple, black, green/yellow[I tended to pair blue and black for common neutral] or brown, black, brown, black, blue, grey, green/yellow [I tended to pair 2xblack for common neutral] I frequently used 7 core as the newer coloured cables were suddenly thinner and more flexible.

Our own phase colours have had a chequered history, as recently as the 50's they were red, green & blue [at least for the DNO]. Then the green turned to white then yellow about 1965/6. Only a couple of years ago I removed a load of redundant 3 phase kit with paper/rubber singles: red, green, blue & black the earth of course was from the metal conduit.

Don't get hung up on colours, even the armoured and 3c&e have previousely been available in a range of combinations, red, yellow, black and red,red, black were commonly available, as are the harmonised variations. I still have a piece of red, white, blue 3C 3/0.29 in my landing light 2 way switching [house built 1968]View media item 23368View media item 26849.

 

[SUNRAY]

So lets look at the basics of multicore colours, harmonisation and phase colours etc
First I'll ask the question: What is harmonisation?
Second question: Who with?

UK flex was red, black, green (and I have come across red, black, green/yellow) then in between black and green was added combinations of yellow, blue, orange, grey & brown. (I manufactured Disco kit and clearly recall red, black, yellow, blue, orange or grey & green). Then the explosion of variations in the early 70's and I found i was using 7 core: 3xbrown, blue, purple, black, green/yellow[I tended to pair blue and black for common neutral] or brown, black, brown, black, blue, grey, green/yellow [I tended to pair 2xblack for common neutral] I frequently used 7 core as the newer coloured cables were suddenly thinner and more flexible.

Our own phase colours have had a chequered history, as recently as the 50's they were red, green & blue [at least for the DNO]. Then the green turned to white then yellow about 1965/6. Only a couple of years ago I removed a load of redundant 3 phase kit with paper/rubber singles: red, green, blue & black the earth of course was from the metal conduit.

Don't get hung up on colours, even the armoured and 3c&e have previousely been available in a range of combinations, red, yellow, black and red,red, black were commonly available, as are the harmonised variations. I still have a piece of red, white, blue 3C 3/0.29 in my landing light 2 way switching [house built 1968]View media item 23368View media item 26849.

 

[SUNRAY]

3C&E is available in larger sizes and I have seen loads of it in commercial applications running 3 phase.

 

[SUNRAY]

3C&E is available in larger sizes and I have seen loads of it in commercial applications running 3 phase.

 

[JohnW2]

3C&E is available in larger sizes and I have seen loads of it in commercial applications running 3 phase.

'Flat' 3C+E (i.e. like T+E)? If so, as I said, I've never seen, or heard of, any larger than 1.5mm².

Even if you are right (and I presume you must be), I don't think it's really a good excuse for 1.0mm² and 1.5mm² 3C+E having '3-phase colours', since I would imagine that it would be very rare, if it happens at all, for it to be used for L1/L2/L3 (without neutral), wouldn't it?

Kind Regards, John

 

[JohnW2]

Our own phase colours have had a chequered history, as recently as the 50's they were red, green & blue [at least for the DNO].

You give way the age of my incoming supply (I hesitate to call it 'a cutout'), at least, in terms of the 'identication disks (and note the indicated red {and exposed!} insulation of the incoming neutral ). Notice also the 'A', 'B' and 'C' labelling of tails going to the meter! ...

...

I still have a piece of red, white, blue 3C 3/0.29 in my landing light 2 way switching

I also still have some of that in my house.

Don't get hung up on colours, even the armoured and 3c&e have previousely been available in a range of combinations, red, yellow, black and red,red, black were commonly available, as are the harmonised variations.

I'm not 'hung up' on it but, for cables up to 4-core, it wouldn't be unreasonable for the colours to be 'logical' in terms of the most common uses - history is history, so I'm talking about current cables.

Beyond 4-core (or maybe 5-core intended for L1/L2/L3/N+E), there is so much variation in how they might be used that it would be impractical to attempt to standardise colours in relation to application.

Kind Regards, John

 

[SUNRAY]

Beyond 4-core (or maybe 5-core intended for L1/L2/L3/N+E), there is so much variation in how they might be used that it would be impractical to attempt to standardise colours in relation to application.

Kind Regards, John

Even 2 core can be, and is, used for a variety of purposes so let's start there and make it available in all the variations, starting with brown,grey and grey,blue. and let's not forget cream.

 

[JohnW2]

Even 2 core can be, and is, used for a variety of purposes so let's start there and make it available in all the variations, starting with brown,grey and grey,blue. and let's not forget cream.

The difference between cables with 4 cores and those with >4 cores is that the former are very commonly used for purposes which we know and love, whereas the latter are used for a much great variety of purposes.

One size will never fit all. There will always be exceptions to generalisations, no matter how few/many cores (in which case one can use over-sleeving or numbering of cores, or singles), but there will be far fewer of those exceptions with 2, 3 & 4 core cables.

Kind Regards, John

 

[SUNRAY]

The difference between cables with 4 cores and those with >4 cores is that the former are very commonly used for purposes which we know and love, whereas the latter are used for a much great variety of purposes.

One size will never fit all. There will always be exceptions to generalisations, no matter how few/many cores (in which case one can use over-sleeving or numbering of cores, or singles), but there will be far fewer of those exceptions with 2, 3 & 4 core cables.

Kind Regards, John

I have some sympathy with your comment BUT depending on the environment one works in the requirements may be way, way different to the average sparks.
I use 2 core cable far more for DC [possibly floating], loudspeaker, other audio, controls and signalling than I ever do for mains. One year alone I purchased >70Km of speaker cable and I hate to think how many Km of 1 or 2 pair screened I've purchased over the years [10Km extra on top of the original estimate for one job]. I have stock reels of red,black for dc work which is freely available whereas brown,grey and grey,blue are a]difficult to source and b]king expensive. And signalling using earth should be cream... but usually ends up as black or blue or white etc depending on what's already to hand.

As you have pointed out the regular versions of 4 core are rarely the right colours but everyones requirements are different. If you could come up with the ideal colour selection for each of the cable sizes I'm sure the manufacturers would love to hear from you.
In the mean time I'd personally stick with the 4 & 5 core combinations that I most commonly find: brown, blue, black[or red], green/yellow plus grey[or white] for 5C. Generally I can make most sense of those. If I'm in a position where i'm offered a selection of colour schemes, which is frequently the case, I'll obviously look at the current requirement and go with the best combination to suit.

 

[SUNRAY]

Oh and this piece sourced last year in that well known colour scheme: blue, brown, white, red, green/yellow. Yes it is red, I've just double checked.

 

[JohnW2]

I have some sympathy with your comment BUT depending on the environment one works in the requirements may be way, way different to the average sparks.

Yes, of course, but certainly in the case of flat 1.0/1.5mm 3C+E what the 'average sparks' use it for must represent the vast majority of usage of such cable - which makes the colours it currently comes in at least 'illogical'.

I use 2 core cable far more for DC [possibly floating], loudspeaker, other audio, controls and signalling than I ever do for mains.

So do many people, but I would think that's mainly in relation to the smaller CSAs, including many too small to be used for 'electrical' purposes.

I have stock reels of red,black for dc work which is freely available ...

You may well have but, at least if it's for DC 'power', Table 7E of Appendix 7 of BS7671 seems to bve saying that you probably should now be using brown and grey for a floating DC circuit, brown and blue for a negative-earthed DC circuit and blue and grey for a negative-earthed DC circuit

As you have pointed out the regular versions of 4 core are rarely the right colours but everyones requirements are different.

There are certainly 'different requirements' but, as I've said, if a particular cable is very commonly used for one type of application/'requirement', then it would seem to make sense for the colours to reflect that application.

kind Regards, John

 

[sparkwright]

There will never be true harmonisation when folk in the UK can't even decide which colour of a 3 core+E cable should be used as neutral. (The real answer is grey, but please don't comment as we will have pages and pages of total rubbishj to read.)

 

[JohnW2]

There will never be true harmonisation when folk in the UK can't even decide which colour of a 3 core+E cable should be used as neutral. (The real answer is grey, but please don't comment as we will have pages and pages of total rubbishj to read.)

There's no 'real answer', since this isn't defined in any Standard or regulations. Those (probably the majority) who advocate using grey do so (I think) solely because they do not want to perpetuate memories of the days when black indicated neutral - which seems, to me, to be a fairly lame reason!

As I've said, the problem is that the Standards/regs about identification colours do not (to some extent necessarily) take into account the purpose for which a cable is going go be used. In an ideal world, if a particular type/size of cable was very commonly going to be used for an application which required a neutral, it would be available in a version in which one of its cores was blue.

Kind Regards, John

 

[SUNRAY]

There will never be true harmonisation when folk in the UK can't even decide which colour of a 3 core+E cable should be used as neutral. (The real answer is grey, but please don't comment as we will have pages and pages of total rubbishj to read.)

Very true.
Initially I went for Black, it seemed extremely logical at the time. However it wasn't too long before I converted a 3 phase fan to single phase and the junction between armoured cable [r,y,b] and flex [harmonised] soon showed me a better solution.

 

[JohnW2]

Initially I went for Black, it seemed extremely logical at the time.

As I've just written, I think it is precisely because "it seemed extremely logical at the time" (since we were used to the association between black and neutral) that some/many people decided that grey would be better/'safer', since using black would perpetuate memories of that previous association, hence might conceivably make some people forget that black now indicated something potentially more dangerous than neutral!

Kind Regards, John