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New way to wire lighting circuits

Former Community Member
Former Community Member
Hello,


Does anyone know anything about a new rule to wire lighting circuits so that they have a live, neutral and earth running the full length of the circuit? I heard something about this last year but cannot pinpoint it in the 18th Edition Regs.


Apparently, a light now has to be wired so that the neutral running to the switch is USED as a neutral, and not as a switched live.


Anyone else heard of this?


Thanks,


David
  • 0
    Arran Cameron:

    What do you think of the idea of powering ceiling lights from the ring main via a FCU in each room? That way the neutral conductor is available at every light switch.


    The obvious problem is that one faulty electrical appliance will noy only take out all the sockets on that ring, but take out all the lights at the same time.  That's not great at night.


  • 0
    The obvious problem is that one faulty electrical appliance will noy only take out all the sockets on that ring, but take out all the lights at the same time. That's not great at night.

    That's one of the unfortunate side-effects of the current fashion for MCBs and RCDs at the CU. Under the original design 13A fuses discriminated very nicely with 30A CU fuses, which in turn discriminated very nicely with 60A supplier's fuses. Other than gross overload the only way you could blow the 30A fuses was a fault on the ring itself. Appliance faults could only disconnect the faulty appliance.

       - Andy.
  • 0
    " The obvious problem is that one faulty electrical appliance will noy only take out all the sockets on that ring, but take out all the lights at the same time.  That's not great at night. "


    Like said . Us front enders have the same problem (or rather do not have much of a problem in practice for more than 25 years)
  • 0
    Using a switched spur also might look a bit odd when you require more than one switch. 3 spurs in a line would be daft.  I suppose you could use a grid then only one fuse with multiple switches.  Still not a good design though losing all lights and sockets in one hit.



    Gary
  • 0
    NArran Cameron:

    What do you think of the idea of powering ceiling lights from the ring main via a FCU in each room? That way the neutral conductor is available at every light switch.




    Why not combined 16 amp socket and lighting radials without SFCU as light switches?


  • 0
    In general, for main living areas in a home, I consider it better practice to utilise seperate circuits for power and lighting as is tradditional. I dont like the risk of total darkness due to a single fault.


    I see no harm in connecting a light to a power circuit via a fused connection unit in sheds, garages, and lofts used only for storage.
  • 0
    If AFDDs are mandated, I could see lots of fellas being tempted to combine circuits such as lightning via a spur from a ring. That way only one AFDD is required instead of two!

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