The lady with the lovely hair, Dr Suzannah Lipscomb, talks to some experts about how hazardous it was in the early days of electricity in the home. :eek:
I wouldn’t say “never”, at least in the US. Edison settled on a 110V standard, to ensure 100V at the point of delivery. I have no experience with 110/220/440 standards, but I’ve seen them on old electrical drawings. We nominally use 120/240/480 in the US now, but I think in the past 110/220/440 was common, with possible intermediate values of 115/230/460, and the language is still used by a lot of people who talk about it. I know I was confused because I had heard it both ways, until I had to work on low voltage stuff and read the local power company’s service manual.
Tell me about it. Every damn winter, until I finally put inline switches on all the table lamps.
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The lady with the lovely hair, Dr Suzannah Lipscomb, talks to some experts about how hazardous it was in the early days of electricity in the home. :eek:
[/QUOTE]The first US president to live in the White House after it was wired for electricity in 1891 was Benjamin Harrison. He and his wife refused to touch the light switches for fear of being electrocuted - they made the domestic staff do it. That may have been an overreaction (as well as possibly saying something about his attitude towards the domestic staff if he thought it wasn’t safe to operate the light switches). But, yeah, 19th century electric wiring was not very safe, and it was also often used in horribly unsafe ways, as there was an explosion of new gadgets powered off home electricity.
I was in a fairly new hotel in Las Vegas (The Venetian) in 2002. I plugged in my charger for my fancy new digital camera before going to bed. The next morning, a mile down the strip, I realized the battery had almost no charge. Checking later, the culprit was the wall socket. The room light switch by the door turned the bottom socket of the dual socket on and off, the top socket was always live. At one point, someone unaware of this setup had moved the table lamp to the top socket, leaving the bottom socket empty. So I’d plugged in the charger, we went to bed and turned off the room lights, and the charger went off.
This is a not-uncommon North American setup - where a room, typically a living room, has provision for a free-standing or swag lamp (remember those?) it would be driven by a socket in the room that was controlled by a wall switch near the entrance to the room. But… I don’t remember running across other setups where the one socket is switched but not the other. that take some interesting wiring.
I have lived my entire life in the US and have plugged in many appliances, and have never been shocked plugging a plug into a properly functioning socket. Where do you get the idea that shocking yourself while plugging in appliances is common in the US? (I have been shocked when there was some kind of fault where the screw holding the socket in place was electrified, but that’s not the fault of plug design). The idea of plugging in a TV by somehow holding the metal prongs of the plug is bizarre, I’m not sure what would even prompt someone to do that instead of just holding it by the plastic part.
This is why my appliances all either have an off switch or are something you don’t turn off (like an alarm clock). The idea of leaving appliances with unplugged plugs sitting around is just weird to me, and the majority of plugs that I use are in locations where getting to the plug itself is difficult (behind a couch, bed, table, etc).
I have a George Foreman grill that doesn’t have its own power switch so a switched socket is really useful.
I’m gonna need a cite here because the current recommendation is to evaluate each circuit in the design stage and decide upon the method of installation based upon allowed disconnection times - and this can vary according to many situations such as length of run, current to be supplied, environment and protective device - that’s just a short list.
The spur circuit to which you refer is in fact called a radial circuit and is not a common method of installation - being usually confined to specific purpose outlets such as supply to your garage, outdoor waterproof outlets etc
So, if you can quote me the IEEE On Site Guide or the current wiring regulations that give this advice as a default instead of an option I would be really grateful.
Ring circuits offer more flexibility post installation because they make it possible to run radial spurs from them - a serious limitation of a radial circuit is that if you need to add more services there is a strong possibility that you cannot because you may have runs that are too long which will lead to unacceptable disconnection times, or even (though unlikely and somewhat counter intuitively) the volt drop across the run is not acceptable or perhaps the possibility of overloading the conductors closest to the source (the reason being that installation is often done at the very limits of acceptability in new build)
As for our plugs, if you are non UK then you may not be aware of our protective device arrangements. In a ring main the protective device is most likely to be 40amp to 60 amp - so if you develop a fault in an appliance whose power cord rating is 13 amp - well you can see the problem, so instead we also have a fuse in the plug itself. This means power cords can be rated for as little as 3 amps because we install a 3 amp fuse to protect that appliance…
The protective device in the mains box is there to protect the wiring, not the appliance.
Nowadays we use Residual current devices, these are similar to the US version of GFCI however, GFCI tended to be voltage operated whereas Residual current devices are, you guessed it - current operated, and were far more sensitive and also discriminate better - that is, you get far fewer false trip outs and also the protective device nearest to the fault is more likely to trip out, instead of a fault blacking out the who house through less discriminating devices.
I believe that the sensitivity of GFCI has caught up over the years, but you could only operate Residual Current Devices (RCDs) in an installed earth system.
Another hugely significant difference between UK systems is that we use installed earths - so we have a 3 wire system. I know that many appliances are 2 wire because they are classed as double insulated but the wiring back to the main dist board is still 3 wire.
There are pros and cons to this approach, but it is easier to protect from certain fault conditions by detecting current flow to ground and protective device fault disconnection is faster.
The UK system is less likely to lead to fires caused by fault current overload - there are many situations where a fault current can flow and overheat a device such that it will burn, and yet the overcurrent is not sufficient to trip the protective device in the dist board, this is why having the fuse in the plug is far better.
Years ago yes.
It’s why Dad kept a supply in the garage. Also why you couldn’t leave anything electrical he didn’t recognise as his in there, he’d whip the plug off nice and quickly for you.
not really, fuse is obvious overkill.
The entire world ( with some exceptions)
lives without fuses in the plugs.
The fridge that burnt Greenfield Tower down had a 3a fuse.
Didn’t help much, did it ?
The following stats on injuries and deaths suggest the UK is one of the world’s more safety-conscious countries:
But I can understand how experience might lead you to form the opposite impression. Some of the people I used to work for were incredibly cavalier about health and safety, and probably still are when they can get away with it. The thing is, though, the large contractors who run most of the really dangerous jobs are regulated very closely these days, and are very leery indeed of getting hit with violations.
Of course, a certain proportion of the workforce continues to moan on relentlessly about health and safety, despite those rules protecting them and causing disadvantage only to their employers. It seems that some regard it as thoroughly unmanly to be unwilling to risk life and limb to help some executive buy a bigger yacht, even though they themselves are barely paid a living wage.
unnecessary rules and regulations impose significant cost on the employers-
cost of compliance .
This cost will eventually be factored into the price of goods and services, making them more expensive for everybody,
including those “moaning” workers.
But the rules and regulations in question aren’t unnecessary, unless you don’t value the safety of the workers. Over the period where health and safety rules became a go-to complaint about excessive regulation, the rate of workplace deaths fell dramatically:
No doubt there are specific cases where legislation has been excessive or otherwise poorly conceived, but the general trend represents a clear improvement in worker safety, to a degree whereby such excesses ought to be seen as the acceptable price of saving a hell of a lot of lives.
On a personal note, if the rules we have now had been in force back in the 60s and 70s, my grandfather would probably have worked another decade, and lived another two. As it was, his lungs were ruined by exposure to poisonous chemicals which, at the time, were regulated little further than the requirement they not kill you immediately.
acceptable to whom ?
Just look at these figures: (PDF)
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=15&cad=rja&uact=8&ved=2ahUKEwjMvf7LrLfgAhW3VRUIHYlNABA4ChAWMAR6BAgAEAI&url=http%3A%2F%2Fwww.nam.org%2FData-and-Reports%2FCost-of-Federal-Regulations%2FFederal-Regulation-Executive-Summary.pdf&usg=AOvVaw3Uu_F1QkXqHaYpY_XduUeP
Kind of like Koreans and can death.
One of those reports is a US one, and the other is from a bunch of hedge fund managers. I’m not sure those really have the interests and well-being of the workers at heart.
What workers ?
Those who would lose their jobs to outsourcing to countries without mad regulations ?
Or,perhaps,workers who won’t be able to find a job in the first place,
because companies can’t afford them ?
Standard new installations here (aus) don’t include wire nuts. If you have to include wire nuts in a new installation here, you probably should run another line from the switchbox 
We don’t run ring circuits. I can’t see that anybody around here would include bus bars in a box just on the off chance that somebody might want them later.
The broader economic case against h&s regulation is barely relevant from the perspective of an individual worker. The potential for loss of earnings through injury (something I experienced myself, albeit as a result of personal idiocy rather than inadequate regulation) is a much more pressing economic concern.
Most people who work in dangerous jobs recognise this, and so are in favour of high safety standards. For those workers who moan, the issue is most often expressed in cultural rather than economic terms: they feel like they’re being treated like children, as if they don’t know how to judge the risks for themselves. The problem is that, much of the time, they don’t. Serious accidents are a low-probability thing - the kinds of dangers we’re bad at judging because we don’t often experience them. For some people, this makes them excessively cautious; for others, it makes them foolhardy. The point of health and safety regulation is to impose standards based on evidence that goes far beyond individual experience. The workers who bang on endlessly about h&s are the ones who won’t accept this, as if it’s some kind of slight on their manhood to follow the advice of ‘experts’ over their own heuristics.
And, yes, we could talk about competitive advantages on an international scale, but do we really want to take a race-to-the-bottom approach on worker safety? Wouldn’t it better for those countries with higher standards (which are, for the most part, the ones with the biggest markets relative to population size) to club together and demand improvements in conditions from those foreign countries and companies that want access to their markets?
Mrs McGinty,
thanks for being reasonable and patient.
I really appreciate that.
But there are regulations and there are regulations.
Nobody argues against meaningful regulations.
The problem is…
government bureaucrats, myriad of controlling bodies,parasitic unions and other self-interested organisations,
local administration jobsworths you name it…
generate a lot of “rules” and “regulations”, which are not based on facts,logic or common sense
but are created simply to justify their own existence.
Who benefits from that ?
This a well-known concept aka market protection.
In the ideal world it (clubbing together) might look like a good idea,
in reality it just creates obstacles for the less developed countries and, as such,
helps the industries,that employ the army of lobbyists and campaign contributors.
Nobody really cares about workers.
Let’s call a spade a spade.