Talk:Old electrical installations

Meter tails

Are old sized meter tails in some way an issue? I thought even old sizes were heavily overspecced. NT 11:01, 28 October 2012 (GMT)

It is not uncommon to come across 10mm tails (and I have seen 6mm tails) and VIR meter tails. I also often see single insulated meter tails that pass through a wall between the meter and the CU. I know that swapping the tails is not a DIY job but the tails are part of the electrical installation and worth a mention. --ARWadsworth 17:56, 29 October 2012 (GMT)

6mm^2 is 47A rated continuous. Greater loads will get drawn, but I don't think for long enough to cause a problem. NT 21:20, 29 October 2012 (GMT)

Much depends on the nature of the appliances in use. In some households 47A is easily swallowed by one big load like a shower. The normal load on top of that (even if only 20A) would be enough extra to become a moderate medium term overload, and hence the risk of cable damage is fairly high.

Re: RCDs; NT, your change of wording to includ "slight" has totally changed the meaning of the statement. Inclusion of a RCD is probably the single most significant contribution you can make to reducing risk of injury from shocks - hence omission of one is a *significant* increase in the risk. That has nothing to do with the likelihood of receiving a shock in the first place.

I think it is irresponsible to dismiss any shock at mains voltage as a "slight" risk. If the circumstances are sufficiently unfavourable, then a mains shock will kill you. --John Rumm 00:45, 31 October 2012 (GMT)

I forget the exact figure but something like half a million A&E visits following shocks a year (so many more shocks), and around 20 deaths, so it is a low risk. NT 01:31, 31 October 2012 (GMT)

Re moderate tail cable overloads, again its the result that counts, ie the number of fires & shock deaths. Running cable insulation at above 70C now and then is quite a different thing to a fire or shock. NT 01:33, 31 October 2012 (GMT)