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Joined: Aug 2001
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It's several weeks since I posted in another thread that my usual supplier was finally carrying the new harmonized cables. Judging by the comments from others, I think this must have been about the last area of the country to see them! It appears that resistance is futile (except in Ohm's Law ) and today I had to come back from the supply house with my first ever purchase of cable in the new colors (a reel of 3-core 1.5mm SWA). The new colors pose a query in situations where a 3-core armored cable is to be used for a single-phase feed with one conductor acting as a supplemental earth to the armor. With the traditional 3-core red/yellow/blue, I always applied black tape or sleeving to the blue for use as the neutral, and green/yellow ID to the yellow for the earth. I wouldn't mind betting that's the way most of us in the U.K. did it. But have any of you adopted a preferred convention for the new cables? Assuming brown is left as-is for the single phase line, which way round would you re-identify the remaining conductors for use a neutral and earth? 1. Black -> Blue; Gray -> Green/yellow; or 2. Black -> Green/yellow; Gray -> Blue.
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Joined: Sep 2002
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I don't quite follow. Why would you use a 3-phase cable for single phase? Are you allowed to turn any conductor into PE and N?
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Joined: Jul 2004
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I don't quite follow. Why would you use a 3-phase cable for single phase? Are you allowed to turn any conductor into PE and N? Well, when terminating in an insulated enclosure it's often easier to run a 3-c rather than t*t about trying to make a bonding terminal using/secured to the armour tag and thus make yet another hole in - say - a weatherproof enclosure. And theoretically you could use any conductor for any purpose if sleeved accordingly ( or taped ), but the designation Paul states in his post was the 'norm' Assuming brown is left as-is for the single phase line, which way round would you re-identify the remaining conductors for use a neutral and earth?
It would appear that the grey is used as the PE when sleeved G/Y Paul - or so I'm told This leaves the black as the neutral which is "easy" to remember!! The 'official' changes are: red>brown, yellow>black, blue>grey. Hmm...officialdom... The 3-core SWA I have on stock has all three brown - you you pays yer money and takes yer choice! I also have 3 browns and a blue ( 4-c) which is a !"£$%^&* nightmare when the clown you have assisting you doesn't clip the ruddy numbers on properly in a nice big enclosure with multiple entries!! Oh well...another adage - "You get what you pay for" !!!!! [This message has been edited by uksparky (edited 11-05-2004).]
If hindsight were foresight, we'd all be millionaires!
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The Irish rules are a little more limiting:
(quote from the ETCI (ElectroTechnical Council of Ireland)
The following limitations apply:
1) Green/yellow cores shall be used only as protective conductors and shall not be converted e.g. by sleeving for use as neutral or line/phase conductors. 2) Blue cores shall be used only as neutral conductors and shall not be converted e.g. by sleeving for use as protective conductors or line/phase conductors. 3) Brown, black or grey cores shall be used only as line/ phase conductors, and shall not be converted e.g. by sleeving for use either as protective conductors or as neutral conductors. 4) 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. 5) For single-core cables used for three-phase circuits, the core colours shall be the same as for multi-core cables. 6) Where single-core cables are used to supply single-phase circuits fed from a three-phase distribution board, the respective line/phase conductor colour may be extended to the single-phase circuits fed from that phase. 7) Sleeving or tape used for identification purposes shall be permanent, heat resistant, colour-fast, non-conductive, and shall comply with EN 60454 or other appropriate standard. 8) Four-core cable without a blue core e.g. NYM-J shall be used only for circuits with balanced three-phase loads e.g. three-phase motors.
(Also the phase order is Brown (L1) Black (L2) Grey (L3)) Single phase systems, just like flexible single phase cables on appliences, use Brown as the live.
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Armored cable aside, there are also times when we need to re-identify the cores of regular 6243Y 3-core cable as well. (That's the 3-core plus earth version of our common "Twin & earth" style cable.) If using this to feed a timed bathroom fan, for example, you would need the red and yellow to provide permanent-live and switched feeds, with the blue tagged black to become the neutral. It would appear that the grey is used as the PE when sleeved G/Y Paul - or so I'm told This leaves the black as the neutral which is "easy" to remember!! The 'official' changes are: red>brown, yellow>black, blue>grey. Ah yes, the R/Y/Bu phases have become Bn/Bk/Gy, so if we adopted a straight substitution I guess that would leave black to be re-identified as earth and gray to be taped/sleeved blue for neutral. I'm not sure which scheme I like the sound of yet! The Irish rules are a little more limiting: Reading that list it seems as though the only permitted change of colors is to re-identify from one phase to another. [This message has been edited by pauluk (edited 11-06-2004).]
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If using this to feed a timed bathroom fan, for example, you would need the red and yellow to provide permanent-live and switched feeds, with the blue tagged black to become the neutral. Well actually you would need the brown and black to provide permanent-live and switched feeds, with the grey tagged blue to become the neutral on a straight substitution! Just how excruciating is that!?! I forsee many splinters as sparkies scratch their heads for years to come... Paul, it occurs to me; how has your supplier got around the supplying of products that should not have been available after the 31st March? [This message has been edited by uksparky (edited 11-07-2004).]
If hindsight were foresight, we'd all be millionaires!
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how has your supplier got around the supplying of products that should not have been available after the 31st March? There's nothing to get around. According to the Regs. the new colors have been permissible since March 2004, but cables to our traditional colors can still be installed until March 2006. Despite the rest of the mess of the changeover, at least the IEE had the sense to allow a 2-year changeover period. I don't think there will be anything to stop anyone from selling cables to the old standard after March 2006, if they happen to still have any in stock.
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Joined: Jun 2004
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According to the Autumn 2004 issue of NICEIC Connections, the method to be adopted should be Brown - phase, Black - PE and Grey - neutral.
The reasoning behind this is to try and stop the association of black being a colour associated with the neutral. They recommend in all circumstances black should never be used for a neutral connection.
Ian
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I suppose that as black will now be phase B they might have something there, but considering the millions of installations in which black (without re-identification) is already a neutral is does seem a moot point.
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Joined: Jul 2004
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Uhuh...sorry Paul you're quite right! I must confess to not reading the bumph too closely and just accepting the change. However, on the flier we received from our supplier we were not able to obtain 'old' cables after 31/03/04 "as [they] are no longer permitted to sell them".
What a mess...
If hindsight were foresight, we'd all be millionaires!
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