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Multicore cables (YY but not PVC/PVC)

I wonder if I could previal for some learned opinions.


We undertake installations of stage lighting amongst other things, and often use a 19-core 'YY' type cable (though it isn't really YY as the insualtion and sheathing is not PVC/PVC - it is a LSF variant) for links between switched power units or dimmers and internally wired lighting bars.


We have undertaken many such installations, and we are registered with the NICEIC who have audited and inspeced many such installations and passed them.  We have also raised specific questions with them on the use of the cable and we get varying answers.  They are never willing to give an emphatic 'yes', but neither do they say 'no'.


As I understand it - there is not a relevant construction standard that covers this type of cable construction, so it can't comply with a standard that doesn't exist.  There are however many standards (many of which form normative references for construction standards of other cable types) with which it does conform.  These include EN 50525-1 (General requirements) EN 60228 (conductors) and various fire performance standards (EN 50575, EN 60754, EN 60134 and EN 60332).  We also know that the insualtion and sheathing material is standards-compliant and is commonly used in cable manufature.


We are embroiled in a dispute with a main contractor who is claiming the installation is non-compliant as the cable does not meet a construction standard. Reg 511.2 allows for use of euipment not covered by a Britsh or Harmonised standard if the designer/specifier confirms that the equipment provides at least the same degree of safety.  This cable is covered by multiple standards but not a single 'construction' standard that is applicable to this type


We have undertaken what we believe to be a thorough assessment of this cable which is attached here:  Assessment of Cable NILTOX LF 319.docx


The use of the cable is noted on the certificate and the assessment and supporting documentation from the supplier is attached, but the main contractor is still refusing to accept this route.


So a couple of questions for the learned community:
  1. Have we missed anything in our assessment, or does it seem thorough and complete?

  • Should the use of this cable be recorded as a 'departure' (our agument is that we have complied with 511.2 and therefore it is not a departure) or just recorded as a note?


Thanks in advance.  Happy to answer any further questions.


Jason.
Parents
  • David - answers as follws:


    The cables are terminated to a terminal box on an internally wired lighting bar at one end, and to the bypass dimmer at the other end, so basically from dimmer/switch pack to fixtures.


    They are in trunking at the dimmer room end, flexible conduit at the IWB end and on basket above a false ceiling in between.


    He would be satisfied with any BASEC approved cable or cable to a British or Harmonised constructon standard.  We could use T&E, or a multicore SWA, or 'socapex' cable (to a Harmonised standard) or multiple 3-core flexes - not that I am suggesting that all of these would be a 'good' solution but they would satisfy this individual.  The use of this cable was convenient to us as it is easy to install. The IWB is on fairly long stud drops so may be subject to slight movement.


    I'm not certain there is a direct clause relating to LSZH but it would fall under the general requirement for cables to meet the Constructon Products Directive (which it does).


    Graham - I'll check out the info in the OSG, but our approach was to provide an equivalent assessment as-per 133.1.3.


    Olympus - thanks for the info on the typo.


    Jason.


Reply
  • David - answers as follws:


    The cables are terminated to a terminal box on an internally wired lighting bar at one end, and to the bypass dimmer at the other end, so basically from dimmer/switch pack to fixtures.


    They are in trunking at the dimmer room end, flexible conduit at the IWB end and on basket above a false ceiling in between.


    He would be satisfied with any BASEC approved cable or cable to a British or Harmonised constructon standard.  We could use T&E, or a multicore SWA, or 'socapex' cable (to a Harmonised standard) or multiple 3-core flexes - not that I am suggesting that all of these would be a 'good' solution but they would satisfy this individual.  The use of this cable was convenient to us as it is easy to install. The IWB is on fairly long stud drops so may be subject to slight movement.


    I'm not certain there is a direct clause relating to LSZH but it would fall under the general requirement for cables to meet the Constructon Products Directive (which it does).


    Graham - I'll check out the info in the OSG, but our approach was to provide an equivalent assessment as-per 133.1.3.


    Olympus - thanks for the info on the typo.


    Jason.


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