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Reference Methods

Former Community Member
Former Community Member
Wondered what installation reference method people might be using for a T&E cable on a masonry wall that is then covered with plasterboard, ie a typical dot and dab affair. I think "C" is correct as all installation methods involving a cable in contact with a wall and NO insulation map to reference method "C". Wouldn't think the plasterboard or covering the cable with capping would make any difference. I raised the question due to seeing A,B, & C on various other contractors certs.
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  • mapj1:

    You may find that attaching the cable to a wooden 'heat spreader' means that side is better cooled - wood is not a good thermal conductor, but it is more conductive than the average block of celotex or what have you. A 3 or 4 inch dive in celotex would not worry me on 2.5mm cable or larger.  By the time we are much thicker on the insulation I might be derating or slipping a metal plate or metal capping in there to diffuse the heat out a bit.


    How the hell is a sparks supposed to know the U value of any insulation? (Methods 100 - 103, table 4A2.)


Reply
  • mapj1:

    You may find that attaching the cable to a wooden 'heat spreader' means that side is better cooled - wood is not a good thermal conductor, but it is more conductive than the average block of celotex or what have you. A 3 or 4 inch dive in celotex would not worry me on 2.5mm cable or larger.  By the time we are much thicker on the insulation I might be derating or slipping a metal plate or metal capping in there to diffuse the heat out a bit.


    How the hell is a sparks supposed to know the U value of any insulation? (Methods 100 - 103, table 4A2.)


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