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OSG 7.3.2 cables in walls and partitions

hertzal123
In the above,item d states the cables can be protected by earthed steel conduit or,

Item e then states :mechanical protection sufficient to prevent penetration of nails,etc,

but no mention of earthing..

I have a situation with a short 200mm horizontal run outside the zones.

I could slide a lenght of earthed conduit over,but then the earth connection would be plastered

over and could not be inspected.

If I treat the conduit as mechanical protection,it would not need earthing?

Wondered what others would do.

                                                        Regards,Hz

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    Presumably it has been tested for occasions where a nail may just penetrate the aluminium covering part and touch the phase conductor as well. Or is the cable only compliant for burying out of zones if the C.P.C. is also touched by the invading nail?





    I believe the BS 8436 test involves a 1.6mm dia nail connecting just the foil to a line conductor - e.g. https://www.fpcables.co.uk/6_NAIL_PEN.pdf


    Presumably the situation is helped by the foil being in contact with the entire circumference of the nail and then (a bit like the soil surrounding an earth electrode) the effective c.s.a. of the foil gets significantly larger quite quickly as the current moves away from the nail.


       - Andy.

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  • 0

    Presumably it has been tested for occasions where a nail may just penetrate the aluminium covering part and touch the phase conductor as well. Or is the cable only compliant for burying out of zones if the C.P.C. is also touched by the invading nail?





    I believe the BS 8436 test involves a 1.6mm dia nail connecting just the foil to a line conductor - e.g. https://www.fpcables.co.uk/6_NAIL_PEN.pdf


    Presumably the situation is helped by the foil being in contact with the entire circumference of the nail and then (a bit like the soil surrounding an earth electrode) the effective c.s.a. of the foil gets significantly larger quite quickly as the current moves away from the nail.


       - Andy.

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