Bjarney,
The outer sheathing of the SWA cable referred to in your link is PVC.
SWA cables should be terminated in brass cable glands that grip the wire armouring, & an earth tag which enables a crimp lug with earth wire to be attached.
We are still permitted to use the wire armouring as a circuit protective conductor (EGC in US terminology) in most circumstances. However it is increasingly common for 3 core cables to be used instead of 2 core in single phase circuits to provide a copper cpc/earth wire in addition to the wire armouring.
Trumpy,
I would like to see our T&E cables changed to incorperate an insulated earth core, but it's true they are bare. Incidentally, we have been required to insulate & identify bare earth cores at terminations since the mid to late 1960's. Originally plain green sleeving or tape was used, after Dec 1977 green & yellow was the only colour acceptable for identifying earth wires.
Green & yellow sleeving is widely available, & at less than £4 for 100M it is not expensive.
Paul,
I don't understand your dislike for the adoption of g/y as the colour for earth wires.
We both know it was done for sound safety reasons, colour blind people. A striped conductor stands out to all.
Whoever came up with the idea of g/y as the international code for earthing cables was a genius. One day even the US will adopt it.
I understand what you are saying about some cables only having a thin stripe(s) of green on a yellow base. G/Y cables are supposed to have not less than 30% of either colour, & not more than 70% of the other colour, if you understand what I am trying to say.
I only use British made, BASEC approved, branded (AEI, Pirelli etc.) cables & these are usually fine, but I have noticed some earth sleeving appears to be more than 70% yellow. Either way it still has 1 or more green stripes, making it apparent that the conductor is for earthing.
