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Discuss Ring main not originating in the DB. in the Electrical Wiring, Theories and Regulations area at

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  1. andygosmore

    andygosmore Guest

    It's obviously not good practice, but is there a specific reg prohibiting a 4mm from the board to a remote rcd a few metres away, & then a 2.5mm ring from the rcd, round the sockets then back to the rcd. I've come across it on a PIR, and unsure whether to pull it up or not.
  2. ackbarthestar

    ackbarthestar Forum Mentor

    A Zoo near YOU
    None as far as I can see. It doesn't feature as a conventional circuit in the OSG, but then if you do the sums and check the installation method and any other correct factors, it should be Ok.

    I believe they call that type of circuit a 'loolipop'

    A note on the PIR/EICR stating there are loolipops in the house should do it !
    • Like Like x 2
    Last edited: Feb 21, 2012
  3. jase

    jase Electrician's Arms

    in effect the 4mm is just acting as a submain to the RCD and then a ring main off of it, this would be no different than an SWA going down to a remote RCD board in the shed and a ring main coming of of that,
    as long as the calcs work out
    • Like Like x 3
  4. Engineer54

    Engineer54 Guest

    For futher reading on this subject, check out ''SIMILAR THREADS'' at the bottom of this page!!
  5. Dannyspark

    Dannyspark Active EF Member

    I can't remember the exact reg number, but I'm sure their is a requirement to fuse down at any point where their is a reduction in csa. From your description it sounds as though you only have an RCD locally protecting and not a fuse/mcb?
  6. GT1

    GT1 Guest

    2 x 2.5mm isnt a reduction in CSA from 4mm though..
    It's an increase in CSA.
    • Like Like x 1
  7. ackbarthestar

    ackbarthestar Forum Mentor

    A Zoo near YOU
    Because its ac it make sense that it would be oversized on the first half cycle and undersized on the second ?:dizzy2: :)
  8. ezzzekiel

    ezzzekiel Guest

    LOOLIPOP - i love it
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