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7/.029 Twin & Earth Cable.

Zoomup
I have a job to update an old installation. It was probably installed initially in the 1960s. There are many radial circuits that would have run to just one socket outlet, probably a 15 Amp type with round pins. The cable is in excellent condition and I will retain the radial circuits and use 16 Amp R.C.B.O.s for each radial circuit.


The wonderful thing about the cable is that it is so flexible. Also the live conductors have seven strands and the earth has three stands of wires.


Wonderful British made cable, unlike the tough 2.5mm2 metric stuff.


Z.
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    Agreed, flexible despite the generally much thicker sheath too.  I have seen some where the cores have become blackened but most is bright and good as new.
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    statter:

    Agreed, flexible despite the generally much thicker sheath too.  I have seen some where the cores have become blackened but most is bright and good as new. 


    I believe that the cable that I have found has tinned copper conductors. Nice and shiny.


    Z.


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    They do tend to suffer from individual strands snapping off over time though.
  • 0
    Zoomup:
    statter:

    Agreed, flexible despite the generally much thicker sheath too.  I have seen some where the cores have become blackened but most is bright and good as new. 


    I believe that the cable that I have found has tinned copper conductors. Nice and shiny.


    Z.




    Hope that it not nice shiny aluminium...

    Clive


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    wallywombat:

    They do tend to suffer from individual strands snapping off over time though.


    But I believe, only if the strand has been nicked, otherwise they are as good as the day they were made.


    Z.


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    AncientMariner:
    Zoomup:
    statter:

    Agreed, flexible despite the generally much thicker sheath too.  I have seen some where the cores have become blackened but most is bright and good as new. 


    I believe that the cable that I have found has tinned copper conductors. Nice and shiny.


    Z.




    Hope that it not nice shiny aluminium...

    Clive




    Nope Ancient, shiny tinned on the outside and copper on the inside. 


    Edit. Add. The cable must have been made at the transition time from rubber insulated to P.V.C. insulated cables, as the P.V.C. is slightly silver in colour. There must have been stocks of tinned wire available. The copper used to be tinned to prevent a chemical reaction of copper with rubber insulation. Obviously when copper was insulated with P.V.C. the tinning process was then unnecessary.

    Microsoft Word - IM-01 Doble.doc


    Z.

     


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    Copper is not a friend of sulphur which is found in rubber insulation.

    Copper and Sulphur reaction - Bing video


    Z.
  • 0
    Obviously when copper was insulated with P.V.C. the tinning process was then unnecessary.

    But standards probably took a while to catch up - as far as I recall all the imperial copper conductors were tinned even though the insulation had been PVC for years. As I recall they only dropped the tinning when they moved to metric (and solid conductors for the smaller sizes).

      - Andy.

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