Maximum no of sockets on spur

Discussion in 'Electricians' Talk' started by Jaydee, Nov 13, 2003.

  1. Jaydee

    Jaydee New Member

    Could someone advise me what is the maximum permissable no of 13 amp switched sockets run as a spur in 2.5mm cable off a ring main is?

  2. supersparky

    supersparky New Member

    You can have as many spurs as there are sockets on the ring. you cannot spur off a socket twice, i.e. one spur for each socket

  3. unphased

    unphased Screwfix Select


    The way around this is to include a fused connection unit on the spur. You can then run "more than one" (how many depends on what you are going to use on the circuit) and the 13A fuse in the FCU is then serving to protect the cable on the ring from overload on the spur.
  4. ban-all-sheds

    ban-all-sheds New Member

    You can have as many spurs as there are sockets on
    the ring. you cannot spur off a socket twice, i.e.
    one spur for each socket

    And for some utterly unfathomable reason, even if you're spurring off from junction boxes, i.e. not trying to have more than 1 spur cable coming out of a socket, you still can't have more spurs than sockets
  5. unphased

    unphased Screwfix Select

    It may have somthing to do with the common practice of plugging in a bank of sockets on a flex, plugging triple plug adaptors in to each and then plugging 101 appliances in etc. etc. ...the DIYers answer to it!
  6. ban-all-sheds

    ban-all-sheds New Member

    Well - that really has got nothing to do with it. The problem of multi-way extension leads and adapters is irrelevant, whether they are plugged into spurs or rings, because there's still a 13A fuse in the plug. What I'm talking about is the basic existence of the spurs, and the nonsensical notion that somehow a spur is safer if somewhere it has a "matching" socket on the ring.

    Imagine a ring with 8 sockets on it, and 8 spurs, some or all of which are wired in with junction boxes. This is perfectly OK, according to the regs.

    Now imagine a ring with 8 sockets on it, and 9 spurs, some or all of which are wired in with junction boxes. This, according to the regs, is not allowed.

    But if you then inserted a 9th socket somewhere in the ring, all of a sudden it would be OK, even though it is blindingly obvious that the mere insertion of a socket does absolutely nothing to the current flow anywhere in the ring, or in any of the spurs, and so does not make it one jot safer. One wonders what the point is of a regulation like that if it has no bearing whatsoever on safety. In fact, you could argue that it actually makes it worse, since any cut in the cable where a socket is inserted produces the potential for the ring to break at that point.

    What's even more bizarre is that the regulations do allow radial circuits with as many legs as you like to supply sockets, even though radials are demonstrably less safe than rings. So you could run a cable from your CU which had several junction boxes on it to create spurs, or legs, going to sockets, and that woud be OK. However, as soon as you attached the far end of the main cable back to the CU to make it a ring, and therefore safer, that would not be OK.

    It's a funny old world.
  7. Robert Jacobs

    Robert Jacobs New Member

    Am I the only one who read the original question, as I am sure it was intended.
    How many 13a switched sockets is it permissible to add to a single fused spur?
  8. spirits are real 2016

    spirits are real 2016 Active Member

    you can have maximum one double socket as a normal spur but if you are going from socket to FCU fused at 13 amp from there you can add as many sockets as you wish as all the sockets and cable will be protected by the fuse so no chance of overloading the cable the fuse will blow first.
  9. Coloumb

    Coloumb Well-Known Member

    I wish SF would put a look on posts older than a year.
  10. Bazza

    Bazza Well-Known Member

    And look at the “New Member” who authored posts #4 and 6 !!
  11. Sam09862

    Sam09862 New Member

    I spur for one soc

    As many as you want. BUT you need to install a 13A FCU before the first spur.
  12. Bazza

    Bazza Well-Known Member

    Post is from 2003:mad:

Share This Page