Brown, Blue, Black and G/Y flex?

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and your only wanted 1 foot or 2 from what I recall !
That was rather different - nothing to do with core colours but, rather, the fact that I was looking (not very successfully) for 1 or two metres of 6-core flex, but eventually realised/discovered that 7-core (although not 6) is pretty readily available.

Kind Regards, John
 
Seen it in white a lot, mainly for single phase and a permanent Live, confusion comes as its not always consistent what is used as permanent live, some use black and some brown.
Hagar tend to use Black as Permanent live in there prewired plugs, and that seems to be the most common way.
https://www.electricaldirect.co.uk/...MI2P2uloup5AIVzLHtCh0v2QO-EAQYBCABEgKz2_D_BwE

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Seen it in white a lot, mainly for single phase and a permanent Live, confusion comes as its not always consistent what is used as permanent live, some use black and some brown.
well, no matter what the colours were, in the absence of any 'regulations', I don't think there would ever be consistency!
Hagar tend to use Black as Permanent live in there prewired plugs, and that seems to be the most common way.
Interesting. I have to say that is the opposite of what I would almost certainly do myself - since, in 3-core (single-phase) cables, brown id the ('permanent') L, I would almost certainly stick with that when I used 4-core, using the 'other colour' (black or whatever) as the S/L.

Kind Regards, John
 
You used to be able to get anything from 4 to 7 core flex with the additional cores all black. They needed numbering or sleeving to ID them.

Easiest way to determine the blacks was by referencing the colours to each side of it.
 
I think all harmonised-colours 4-core flexes I've seen (and used), plus things like SWA, have had brown, black, grey and G/Y cores. My point was that I don't recall ever having seen brown, blue, black and G/Y before - have you?
IIRC grey cores were introduced when the UK moved to harmonised colors for fixed-wiring cables in the early 2000s because the UK objected to having multiple black cores in standard 3-phase cables.

All the 4-core flex I saw in the 90s (admittedly not much) was brown/blue/black/g+y like the stuff posted here.
 
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Interesting. I have to say that is the opposite of what I would almost certainly do myself - since, in 3-core (single-phase) cables, brown id the ('permanent') L, I would almost certainly stick with that when I used 4-core, using the 'other colour' (black or whatever) as the S/L.

Kind Regards, John

I would quess there use of Brown is because the normal 3 core version, which is mainly designed for connecting normal lights to a single or multi output Klik box, fed from a switched supply as well as a permanent supply (usually via a key switch), uses Brown as what would then be a switched live.

To this day i always open the plug to check as there is no way of knowing for sure, as often the flex is installed by the user rather than buying the preassembled units. we proberly find about 3 lights a year, that go on to emergency when the lights turn off. due to the Brown and Black reversed.

It also seems to be the habit lately of finding Pirs connected using these 4 pin plugs and basically feeding back into the lighting system via the plug. again using the black core.
It dont seem right but i suppose unlike a "Widow maker" the plugs dead as all live pins break simultaneously on removal.

Though when I connect standard Pirs to normal circuits, without these klik plugs, I do what you say and use the Brown as permanent live, though cannot explain why.
Maybe the association of Brown in an appliance flex being Permanent live.
 
No, of course not - I use 4-core flex 'all the time' :)

I think all harmonised-colours 4-core flexes I've seen (and used), plus things like SWA, have had brown, black, grey and G/Y cores. My point was that I don't recall ever having seen brown, blue, black and G/Y before - have you?

Kind Regards, John

4 core flex is almost always green/yellow, blue, brown and black.
 
4 core flex is almost always green/yellow, blue, brown and black.
Our experiences clearly differ. I've used a fair bit of 4-core fles, and have a fair bit 'on my shelves' but, as must be apparent from the fact that I started this thread, I've never seen those colours used before.

I'm certainly not at all sure about 'nearly always'. Having just had a very quick look, the five suppliers I most commonly use (TLC, QVS, RS, Denmans and Screwfix) are all selling 4-core flex with brown/black/grey+G/Y (which is what I've always seen) - I wonder where you get your "green/yellow, blue, brown and black"? ...

TLC ....
upload_2019-8-30_13-5-48.png


QVS ...
upload_2019-8-30_13-6-42.png


RS ...
upload_2019-8-30_13-12-6.png


Denmans ...
upload_2019-8-30_13-7-37.png


Screwfix ...
upload_2019-8-30_13-8-33.png


Kind Regards, John
 
aptsys is talking about the "old colours" ... and you are looking at "new colours" available now.
Are sure about that?

For a start, what part of "... IS almost always..." refers to decades ago? ... and, even if it did, would "blue, brown and black" really have been acceptable under the 'old colours' (when black was neutral and brown had {as far as I am aware} no defined meaning for LV AC wiring)?

Kind Regards, John
 
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Are sure about that?

For a start, what part of "... IS almost always..." refers to decades ago? ... and, even if it did, would "blue, brown and black" really have been acceptable under the 'old colours' (when black was neutral and brown had {as far as I am aware} no defined meaning for LV AC wiring)?

Kind Regards, John
The colour code for flex was harmonised decades before non-flexible cables.
 
So flex was harmonised is 70’s ?
So it had brown blue then.

Then in 2008 ish grey was introduced.
 

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