Confusion on Wiring Colors

Discussion in 'Electricians' Talk' started by Lemmor, Mar 24, 2011.

  1. Lemmor

    Lemmor New Member

    Hi All,

    I am sort of confused here, there seam to be no clear indication on specific color marking for the neutral and earthing conductor???

    If 3 core SWA cable or 6243Y cable is used, colors are brown, black and grey, where broun is L1(Line) but what happens with black and grey in a single phase installation???

    I have come across some the following, Black used as Neutral conductor Blue marking and Grey used as Earthing Conductor Green / Yellow marking also
    Black used as Earthing Conductor Green / Yellow and Grey used as Neutral conductor.

    Which one is correct and why, also regs are not very Clear at all in section 514 and appendix 7
  2. CraigMcK

    CraigMcK Screwfix Select

    If you have a 3 core cable with Brown, Black, Grey it's a 3 Phase cable, ie no neutral. If you want a L/N/E cable it should be Brown, Blue, G/Y. If you are finding cables being marked it's because they used the wrong cable and had to identify the ends
  3. seneca

    seneca Screwfix Select

    There's nothing wrong with using brown/black/grey cable, in fact I can't remember seeing brown/blue/green & yellow swa.  The accepted colour code is now, L-brown,  N-grey sleeved blue & E-black sleeved green& yellow.
    SapperGilly likes this.
  4. spinlondon

    spinlondon Screwfix Select

    There's no set way to do this.
    The NICEIC want to de-neutralise the black, so they recomend using the black as the earth, and the grey as the neutral.
    Others are of the opinion that as black used to be neutral, then there's nothing wrong with it still being used as netral in these circumstances.
    Of course you then have the problem, where fittings require a permanent and switched live.
    Often the terminals are marked as L1 and L2, wich logically would suggest brown to L1 and black to L2 (as that is their designations with 3 phase) again this would leave the grey as neutral.
    At the end of the day, as long as the core is correctly identified by either color or alphanumeric means, it shouldn't really matter what colour is used.
  5. J.P.

    J.P. New Member

    Concur Sen..all logical M8.
  6. crackedwolf

    crackedwolf New Member

    In a nut can use whatever cores you like as long as they are sleeved correctly and the same each end!!!. neutralise the black just shows what madness we have to put up with, sleeve the black blue and re neutralise it. :)
  7. J.P.

    J.P. New Member

    I would think its best to sleeve according to current convention..thus would use Sen's coding. Forget about the NIC and stuff, they meddle in things to much.
  8. bluevelvet

    bluevelvet New Member

    S.W.A. in brown-blue-green/yellow is readily available at most wholesalers,if you ask for it. At the end of the day,as long as you fully identify all cores
    you can use what ever colour you want. 
  9. J.P.

    J.P. New Member

    Must say am not happy with the oversleeve idea though generally. I mean if you was using the brown/black/grey sleeved for L/N and E..then apart from source and end..the cable in between would not have correctly identified core use. For instance if a DIY chap such as myself wanted to ''whip off a rad'' from the middle, then it might be confusing as to what is the earth and stuff. .just saying like.
  10. fooman

    fooman New Member

    You agree with anyone and anything JP

    expecially when Lucy is not here keeping an eye on you ;)
  11. unphased

    unphased Screwfix Select

    It does matter what colours are used for neutrals and earths etc. If we all did the same thing it wouldn't matter. But because every electrician seems to have his onwn favourite way of doing something we all get in a mess. It matters moreso when sleeving is not used where it should be and there are enough sparks out there who don't bother. When another spark comes along and has to bell it out it gets troublesome. I wish we could adopt the grey as neutral advocated because the black is then not associated with the old colours. Old colours are just that, old co0lours so there is no l,ogic in trying to make black a neutral.

    Brown is always L or SL, black is always SL, grey is always neutral. What can be simpler?
  12. sinewave

    sinewave Screwfix Select

    Except when Black is an L2  Phase and Grey is an L3 Phase!  
  13. Lectrician

    Lectrician Screwfix Select

    Brown/Blue/GY is available, but usually pricey when compared to Br/Bl/Gy.

    As said above, convention is Black as Earth and Grey as Neutral for previous reasons mentioned, but also, when transposing RED YELLOW BLUE to BROWN BLACK GREY, it can be seen the old blue is now the grey, and as we used to use the blue as a neutral in single phase armoured, it makes sence to use the grey now (and dido for the yellow as earth, now black).
  14. Darth Maul

    Darth Maul New Member

    Should have gone for a 2xcore & used the SWA as the earth. Reason is you have to use the shrouds & banjo it anyway so save time doing 2 x jobs at once, Unless there is a reason you cannot use the SWA as the earth?    

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