1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Chocolate box wiring

Discussion in 'Electrics UK' started by ScotchGas, 4 Jun 2018.

  1. ScotchGas

    ScotchGas

    Joined:
    19 Sep 2011
    Messages:
    74
    Thanks Received:
    14
    Location:
    Glasgow
    Country:
    United Kingdom
    Wiring up one of these for lighting/extractor fan. Never really use them so wondering if I'm better off with a proper wiring box & strip or if this will cope alright.

    E3844B44-6D40-4632-B6B3-22619D7B050F.jpg

    I'm feeding it from a 3a spur to comply with the extractor mi's then has L to fan, l/switch & onto next light. S/L from switch then going to light & extractor.
    Will the choco box cope alright with this or will it be too much?

    (Earths still to be sleeved never had any to hand)
     
  2. Sponsored Links
  3. sparkwright

    sparkwright

    Joined:
    20 Aug 2009
    Messages:
    8,227
    Thanks Received:
    1,019
    Location:
    Dorset
    Country:
    United Kingdom
    What's a chocolate box?

    The picture shows a traditional 20 amp 6 terminal junction box.

    The most I have dared to connect to one of these 8 cables. Would never recommend more than 8.
     
  4. ScotchGas

    ScotchGas

    Joined:
    19 Sep 2011
    Messages:
    74
    Thanks Received:
    14
    Location:
    Glasgow
    Country:
    United Kingdom
    I've just always known these as chocolate boxes

    This has 7, wasn't sure if electrical guys doubled up on the holes.

    I'm fitting a light in the living room since there's not one in there so one of the cables will be going into another box to deal with the wiring for that.
     
  5. sparkwright

    sparkwright

    Joined:
    20 Aug 2009
    Messages:
    8,227
    Thanks Received:
    1,019
    Location:
    Dorset
    Country:
    United Kingdom
    Seems ok AFAICT.

    Would recommend leaving all the wires the same length, around 2 - 2.5 inches.

    You see, the very short wires may break off at the ends, meaning there's zero slack to re-terminate without having to start again.
     
  6. ScotchGas

    ScotchGas

    Joined:
    19 Sep 2011
    Messages:
    74
    Thanks Received:
    14
    Location:
    Glasgow
    Country:
    United Kingdom
    Might just do that, it's in a false ceiling & I've left plenty excess for cables but anything to make life easier in the future.
     
  7. JohnD

    JohnD

    Joined:
    15 Nov 2005
    Messages:
    70,343
    Thanks Received:
    3,972
    Location:
    Crossgates
    Country:
    Cook Islands
    the "wiring centres" used by plumbers are just an improved junction box, but they (usually) include cable grips, numbered terminals, several identifiable sets of connectors, and room in the lid for descriptions and notes. You can often pick up several for a few pounds. I got some in for bathroom connections, to cover lights, fan, shaver socket, etc. They could be useful in kitchens too, for stuff on the lighting circuit. They look to me 10A size but I haven't checked.

    https://www.ebay.co.uk/sch/Heating-Cooling-Air/69197/i.html?_from=R40&_sop=15&_nkw=wiring centre&rt=nc&LH_PrefLoc=1&_trksid=p2045573.m1684

    [​IMG]
     
  8. Taylortwocities

    Taylortwocities

    Joined:
    28 Jul 2006
    Messages:
    20,100
    Thanks Received:
    2,065
    Location:
    Oxfordshire
    Country:
    United Kingdom
    While you are at it, invest in some earth sleeving. Those bare earth conductors need covering up!
    [​IMG]
    PS
    Your picture is a junction box. These are what is commonly known as 'choc block'
    [​IMG]
     
  9. JohnW2

    JohnW2

    Joined:
    28 Jan 2011
    Messages:
    46,696
    Thanks Received:
    3,013
    Location:
    Buckinghamshire
    Country:
    United Kingdom
    I think that is in hand ...
    Kind Regards, John
     
  10. Sponsored Links
  11. EFLImpudence

    EFLImpudence

    Joined:
    7 Jul 2010
    Messages:
    35,750
    Thanks Received:
    3,996
    Location:
    Retired to:
    Country:
    Portugal
    I've asked before but -

    what advantage will a bit of g/y sleeving achieve in a situation like this?
    If a live wire escapes from its terminal, wouldn't it be better that there is more CPC wire to touch and disconnect the supply?
    Or is it the intention to prevent that happening; if so, why?

    upload_2018-6-5_11-58-22.png
     
    • Like Like x 1
  12. Tigercubrider

    Tigercubrider

    Joined:
    22 Jul 2016
    Messages:
    4,111
    Thanks Received:
    659
    Country:
    United Kingdom
    no expert but if a live became disconnected it might tough an exposed earth and make a metal part live.

    maybe no issue if there are breakers but in an older installation that relies on fuses...
     
  13. JohnW2

    JohnW2

    Joined:
    28 Jan 2011
    Messages:
    46,696
    Thanks Received:
    3,013
    Location:
    Buckinghamshire
    Country:
    United Kingdom
    Indeed so.

    I presume that if it were an earthed metal enclosure with (for some reason) just 'exposed' L and N conductors within, no-one would suggest that the inside of the earthed box had to be covered in some sort of insulation.

    As you say, we've discussed this before, but I can't remember exactly what we concluded regs-wise. As far as I can make out, the regs require all conductors (even CPCs) to be 'identified', at least at their ends, so that would presumably require at least 'a bit' of G/Y sleeving on a bare CPC. However, is there actually any regulatory requirement for all of the exposed bare CPC to be sleeved?

    Kind Regards, John
     
  14. JohnW2

    JohnW2

    Joined:
    28 Jan 2011
    Messages:
    46,696
    Thanks Received:
    3,013
    Location:
    Buckinghamshire
    Country:
    United Kingdom
    As I've just written to EFLI, that would be at least as true of live conductors inside an earthed metal box/enclosure (of which there are millions around, and even more now we're being forced to move to metal CUs!) but I don't think anyone would suggest that the inside of such a metal enclosure should be protected by insulation!

    Fuses, just like 'breakers', should operate if an L conductor touches something 'earthed'.

    Kind Regards, John
     
  15. EFLImpudence

    EFLImpudence

    Joined:
    7 Jul 2010
    Messages:
    35,750
    Thanks Received:
    3,996
    Location:
    Retired to:
    Country:
    Portugal
    Exactly.

    Possibly a little bit - but are they not identified by their bareness?

    I think not in the situation pictured.



    Apart from any rules or regulations - in that junction box, would sleeving be advantageous, disadvantageous or immaterial?
     
  16. ban-all-sheds

    ban-all-sheds

    Joined:
    27 Aug 2003
    Messages:
    69,783
    Thanks Received:
    2,858
    Location:
    London
    Country:
    United Kingdom
    Advantageous.
     
  17. EFLImpudence

    EFLImpudence

    Joined:
    7 Jul 2010
    Messages:
    35,750
    Thanks Received:
    3,996
    Location:
    Retired to:
    Country:
    Portugal
    Care to say how?
     
Loading...

Share This Page