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Routing cables through back box

Discussion in 'Electrics UK' started by bsr, 10 Dec 2020.

  1. bsr

    bsr

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    Hello

    I'm moving some sockets and incorporating them in the ring. Currently I have four double sockets on a spur which I know is wrong.

    This is a ground floor room. The ring runs in the ceiling and will drop to each socket. In one place I want two sockets, one above the other. One double socket above desk height for desk lamp and temporary equipment, the other double socket below desk for IT equipment.

    As both sockets will be on the ring, one cable will need to run through the upper socket into the lower one. What do you do here? Do you run the T&E:
    • Behind the box (means a deep chase and inaccessible cable)
    • Through the box (I have 25mm boxes)
    • Around the box (in safe zone but not obvious so I think at risk of damage)
    Alternatively I guess I could put the top box on the ring and then spur the lower socket.

    I'll be chasing into hard red brick so the shallower the chase the better :) It's a half-brick internal wall, tiled on other other side, so cracking a brick will be a pain to fix. I'm using standard depth sockets not fancy flat plate ones so 25mm boxes are fine.

    I can't take the wire horizontally between the two sockets because there's an alcove (not shown).

    Highly artistic picture attached!

    Thanks


    bsr


    wires.png
     
    Last edited: 10 Dec 2020
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  3. DetlefSchmitz

    DetlefSchmitz

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    Through the box - don't see the problem.
     
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  4. sparxxxx

    sparxxxx

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    I would just make it a spur off of the one above.
    If you go through the box you must ensure you leave enough space for the socket to fit in.
     
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  5. sparxxxx

    sparxxxx

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    see above
     
  6. JohnD

    JohnD

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    25mm is not overly generous.
     
  7. DetlefSchmitz

    DetlefSchmitz

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    There needs, in any case, to be room to wire the socket. If there's room for that there is room for a cable running through pressed against the back of the box. But yes, 25mm is a bit tight, I usually use 35mm.
     
  8. sparxxxx

    sparxxxx

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    Only someone that has never done that would suggest that.
     
  9. securespark

    securespark

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    In the 70s and 80s, there was a trend, at least in Manchester and Stockport, to fit 2G 16mm boxes with Ashley sockets on top.

    25mm boxes with a "through cable" is fine.

    I know because I have done it!
     
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  11. JohnW2

    JohnW2

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    Does that mean that you have never tried to do it? In common with others, I have done it in my time, but I agree that it's pretty tight.

    Kind Regards, John
     
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  12. sparxxxx

    sparxxxx

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    Put it another way, while you're struggling to fit the cable around the box, I will have finished the spur and be on the way home.

    Fitting cables around boxes is a last resort solution, and also gets remembered as "seemed like a good idea at the time"
     
  13. EFLImpudence

    EFLImpudence

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    You don't need two cables for the lower socket.
     
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  14. blup

    blup

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    I have just extended a ring using wagos through an existing double socket so four cables in/out in a 25mm back box so what you're proposing is doable.

    Blup
     
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  15. sparkwright

    sparkwright

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    You can run a cable through a 25mm box, and still have room to fit and standard white plastic socket, although products such as Legrand Synergy range have NOT always fitted on such an arrangement.

    A 35mm box was suggested, you could even use the 25mm box just 5mm deeper in the wall.

    If you're that worried, it really wouldn't be the end of the world if you went tightly round the box, but I'm not going to suggest that as there will uproar, so I am not going to say anything about that.

    Or, you could consider having the two boxes slightly out of vertical alignment, if you think that wouldn't be a problem.
     
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  16. bsr

    bsr

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    Wow I didn't expect this many responses! I'll spur it then. I didn't know if it was poor practice to spur if extending the ring was possible.

    Thanks
     
  17. sparkwright

    sparkwright

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    No no no.

    Don't spur it - you may want to add another socket from that point one day, then you'll going to have a struggle.

    (Assuming this is a ring circuit.)
     
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