There is no automatic disconnection mechanism - which is I suspect what is worrying you. There are no RCDs on the low voltage DNO networks,indeed given the way that earth and neutral are connected, even if we wanted to, in most cases there could not be.
If by some means the TT earth and the core of a live meter tail do make contact, everything on that TT zone becomes live, the electricity bill goes up, but there is no other symptom, except that folk may report getting a shock off it, and the power stays on in that dangerous state until the fault has been fixed.
Until very recently the advice was always not to bring any pre RCD live wire and a TT earth into the same enclosure, so there was no place that a stripped meter tail and TT earth could be side by side. So the first thing meter tails did, was to go into a plastic box with an RCD in side and little else.
With the change of rules deprecating plastic consumer units for domestic use, this has now become possible, with a live tail in an earthed metal box, and ideally other steps should be taken to restore a similar level of safety - as others mention above, special glands and spacers so even if the meter tail connection comes loose, it cannot spring very far.
Concentric cable with the neutral on the outside would be safer, and is what the DNOs use, but BS 7671 does not recognise the neutral as safer than live. (Thought ESCQR does)
There is no automatic disconnection mechanism - which is I suspect what is worrying you. There are no RCDs on the low voltage DNO networks,indeed given the way that earth and neutral are connected, even if we wanted to, in most cases there could not be.
If by some means the TT earth and the core of a live meter tail do make contact, everything on that TT zone becomes live, the electricity bill goes up, but there is no other symptom, except that folk may report getting a shock off it, and the power stays on in that dangerous state until the fault has been fixed.
Until very recently the advice was always not to bring any pre RCD live wire and a TT earth into the same enclosure, so there was no place that a stripped meter tail and TT earth could be side by side. So the first thing meter tails did, was to go into a plastic box with an RCD in side and little else.
With the change of rules deprecating plastic consumer units for domestic use, this has now become possible, with a live tail in an earthed metal box, and ideally other steps should be taken to restore a similar level of safety - as others mention above, special glands and spacers so even if the meter tail connection comes loose, it cannot spring very far.
Concentric cable with the neutral on the outside would be safer, and is what the DNOs use, but BS 7671 does not recognise the neutral as safer than live. (Thought ESCQR does)
