This thread has escalated quickly! Thank you all for your inputs really, I tried to read through the other pages of interesting dissertation but unfortunately my mind could only absorb so much.
In the UK, we're getting very close to current regs requiring RCD protection of everything, but given that these requirements are not retrospective, it will be a very long time before that is reflected by by what one sees in all UK installations. However, in relation to what you say, to repeat something I've talked about many times before ....
... I am yet to be convinced of the effectiveness, particularly the ('impassionate') 'cost-effectiveness' of RCDs (or RCBOs) in relation to the prevention of deaths (and probably also serious injuries). For many years, I have been asking (here and elsewhere) people for reports of occasions on which someone has suffered (and survived) an electric shock which has tripped an RCD/RCBO - since those are the only case in which they may have died in the absence of an RCD (i.e. the RCD 'saved a life'). However, I have so far heard of almost no such occurrences.
In terms of 'cost effectiveness', I observe that the very widespread purchase and installation of RCDs/RCBOs has cost an awful lot ('billions') and that the same amount of money spent on other things (road safety, reduction in violent crime, illicit drug use etc.) would probably have had the potential to avoid far more deaths than is the case with installation of RCDs/RCBOs. In the UK, the number of deaths due to domestic electrocution in a year is appreciably less than the number of deaths on the roads, or due to drug abuse, in a week, and not much less than the number of murders per week.
That does, of course, not mean that RCDs are incapable of 'saving lives'. However, their greatest value is probably not in operating at the time of a shock but, rather, in resulting in the clearance of an L-E fault (of too high an impedance to cause an OPD to operate) before anyone gets a shock - but it is essentially impossible to get any statistics about that. However, I would imagine that (in TN installations) most L-E faults are of sufficiently low impedance to be cleared by an OPD, so RCDs/RCBOs probably don't make all that much difference.
True, but there is also the inconvenience (with a standard RCBO) of not knowing whether it has operated as a result of over-current or residual current - some sort of 'flag' to indicate that would be helpful. Another issue is that, at least in the UK at present, the great majority of RCBOs are single-pole, which introduces a few issues.
Kind Regards, John
Thanks
@JohnW2 . (let me be nosy and ask you, I imagine you are the same John W[...] sat by the organ on youtube? I stumbled in some of your videos weeks ago, they are really extremely informational and well explained, I am sure you are not new to this sort of feedback!)
I totally agree with your view. (And eye-opening to know that RCBOs make diagnostics more difficult.)
It is a bit of a "trolley problem", or simply how much is someone's lives worth it? If indeed there are 20+ millions dwellings in the UK and replacing all the circuitry to RCDs / RCBOs is going to cost 1 bln pounds (assuming half the dwellings are fully RCDed and the cost of work+material to upgrade the 10mln dwellings is 100 pound) and then there is a chance, not a certainty, to perhaps save 5 lives per year, then perhaps that money can be diverted anywhere else.
But then again, that is a collective view.
Me as a private citizen, as I might decide I want to pay a ridiculous 4 pound for a loaf of sourdough, I might also decide that for my pocket's worth, spending 100 GBP to just erase from my mind the slightest chance of avoid seeing my partner or children being electrocuted, then be it.
Some people decide it is worth 100 quid a month and their health for the small enjoyment of sucking burnt air through a paper cylinder.
On a different note a new question, as apparently I have some of the brightest electrical minds of the forum over here (!!)
Not to start a dissertation of the wonders of the human mind and be marvelled at how I have been to these friends house several time in the past and never noticed their electrical configuration; last weekend I was at theirs again and noticed for the first time how they have a switch inside for the socket outside.
In this kitchen renovation which was the object of the thread, the ring which has been laid comprises also a socket outside, on the ring. No switch inside.
Does a socket outside need to have a switch inside by reg? If not, is it
really inconvenient not to have one?
I understand the issues with someone might be stealing your electricity (unlikely I dare think), if a fault due to e.g. wind and rain occurs to the IP66 outside socket then with a switch you can isolate that and keep the electricty on in the kitchen (I would hope that IP66 boxes should withstand wind and rain in 99.9% of the cases and we are not in a flood prone area, even though these days who knows).
Essentially I would like to know if I should be bothered/worried at all by not having that switch, and if positive that I should worry I am probably in the last days when I can perhaps introduce a switch without disrupting the newly plastered walls.
Thanks!
