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Meter Tails in Ducting

Hi All,


Working on a street lighting project, which requires a DNO supply. Now, up to this point it has been fed from a SWA as a temporary supply. We are in the process of changing it to its rightful metered supply, however the original installer did not allow space for the cut out/meter. My thinking is to install an adjacent pillar, to house the fused cut out, meter, and duct between the two. 


My question is can meter tails be ducted, they are double insulated so i cannot see why not. Alternatively,, fit a 80A fused switch after the meter and gland from that and run in from the connecting ducts to terminate into the DB. Has anyone used SWA after the meter?


Many thanks
  • SWA is not the thing to connect direct to a meter, but you will  need to convert from tails to the SWA before going very far. 


    Is there a switch or fuse the consumer side  of the meter ? if there is that would normally be the place, if not then an adaptable box and some line taps may be in order

    It needs to be at least as neat as a typical (?) streetlight wiring. !!
  • Hi Mike, 


    Due to this being a whole street, the council have requested the feeder pillar and from there 16mm cables to each streetlight (approx 10) from a DB inside with a metered supply. Some Numpty has not left enough room in said feeder pillar for the cut out/meter making in unadoptable. Therefore, my thinking was to place an adjacent second feeder pillar to house the cut out, meter, and the consumer 80A Switch fuse. 


    The arrangement therefore would be: 80A cut out > DNO Double Insulated Meter tails > Meter > Short Section of Consumer Double Insulated Meter Tails > 80A Switch Fuse > SWA Ducted between adjacent pillars and then terminated into DB.


    How does this sound to you? Never used SWA as consumer meter tails, so really confirming this is okay.


    Cheers

  • My question is can meter tails be ducted, they are double insulated so i cannot see why not.



    If they're going underground then the cable needs to have an earthed metallic armour or sheath to suitable for use as a c.p.c. etc - unless you can show that the ducting provides sufficient mechanical protection to provide equivalent safety (which is usually difficult).

     

    Some Numpty has not left enough room in said feeder pillar for the cut out/meter making in unadoptable



    I'm slightly surprised that street lighting need metering - isn't it usually paid for by licence priced on its nominal power consumption? But anyway, any mileage in simply replacing the pillar with a larger one?


       - Andy.

  • AJJewsbury:




    My question is can meter tails be ducted, they are double insulated so i cannot see why not.



    If they're going underground then the cable needs to have an earthed metallic armour or sheath to suitable for use as a c.p.c. etc - unless you can show that the ducting provides sufficient mechanical protection to provide equivalent safety (which is usually difficult).

    Noted, SWA it is.

     

    Some Numpty has not left enough room in said feeder pillar for the cut out/meter making in unadoptable



    I'm slightly surprised that street lighting need metering - isn't it usually paid for by licence priced on its nominal power consumption? But anyway, any mileage in simply replacing the pillar with a larger one?


       - Andy.

    The Lighting department at the council have requested a metered supply, from my understanding the nominal consumtion is correct if the supply is 500w> and an umetered connection can be applied for. It does make sense to put in a new larger pillar, but it is proving a nightmare trying to coordinate the DNO and the electrical sub-contractor. 




     

  • Former Community Member
    0 Former Community Member
    Would their be a discrimination issue having a 80a cut out and 80 switch fuse. Maybe better to have a switch disconnect on consumer side

  • Would their be a discrimination issue having a 80a cut out and 80 switch fuse. Maybe better to have a switch disconnect on consumer side 



    Not really any issue with discrimination - the effect is the same whichever fuse blows first - the same loads are disconnected either way. If anything there's an advantage in having a consumer side fuse which'll generally be easier to replace than a DNO one - even if there's only a 50:50 chance of benefiting from it.


    Besides there's the issue of the DNO normally only allowing their fuse to provide protection to short lengths of visible insulated & sheathed singles of specified c.s.a.


      - Andy.