EEVblog Electronics Community Forum
General => General Technical Chat => Topic started by: Avacee on March 17, 2017, 05:28:37 pm
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Possible Darwin Award inc :(
http://www.bbc.co.uk/news/uk-39307418 (http://www.bbc.co.uk/news/uk-39307418)
The BBC title is a bit clickbaity since it appears it wasn't the iPhone charger at fault as he'd rested an extension lead on his chest with the charger plugged into it and the charger/extension lead came into contact with the bath water.
Tragic story but imho, it shows a stunning level of ignorance about basic electricity which I'd assume his age would have.
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Interesting would not think a 5vdc source would cause death, wonder if this only applies to cheap Chinese adapters that have no isolation.
Either way messing around with stuff plugged in the wall while in a bath is not very bright. Definitely not 100w.. well he was for a little while I guess.
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Interesting would not think a 5vdc source would cause death, wonder if this only applies to cheap Chinese adapters that have no isolation.
According to the story the man rested a 240 V mains extension cable on his chest and then submerged it in the water. Nothing close to 5 V DC.
(It should be noted that he would have had to use a long extension cable to do this as UK electrical regulations do not permit mains sockets anywhere near a bathtub.)
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That definitely qualifies for a Darwin award.
I did find that odd when I visited the UK, no electrical outlets or switches anywhere in bathrooms, the only thing they did have was an isolated 110V shaver socket. Here in the US I don't think I've ever seen a bathroom that didn't have an outlet in it and most of the time the light switch is inside the bathroom too. Houses from the 1950s often have the bathroom light switch outside the door, something that amused me when I was about 4 years old turning the light off while someone was in there.
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Interesting would not think a 5vdc source would cause death, wonder if this only applies to cheap Chinese adapters that have no isolation.
According to the story the man rested a 240 V mains extension cable on his chest and then submerged it in the water. Nothing close to 5 V DC.
(It should be noted that he would have had to use a long extension cable to do this as UK electrical regulations do not permit mains sockets anywhere near a bathtub.)
Oh yikes, I thought they meant the phone charger cable not the 240v one. Yeah that would pack a nice punch. :o
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I'm going out in style here as I've had a few drinks, but what a fucking moron. It's really hard to kill yourself in the bathroom with electricity here. I mean you have to really try. This guy did the trying in style. He purposely circumvented the safety measures. That's STUPID.
This pisses me off:
"Apple did not respond to requests for a comment."
Good job Apple. It's not your fault your user was an idiot. Does Ikea have to comment when someone stabs a VARDAGAN though someone? Nope.
A coroner ruled his death was accidental and plans to send a report to Apple about taking action to prevent future deaths.
File it in the trash can. Seriously. Also please record the difference between ACCIDENT and STUPID. A loosely coupled chain of causality between several things is an accident. Someone taking direct illogical action that threatens themselves is STUPID.
:palm:
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Dumber than dirt, but also unlucky. How did the path from the mains through him and the tub come to be better than the path through the wires themselves? Unless he was two levels stupid and had modified the mains cable in some way.
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Shallow bath
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Dumber than dirt, but also unlucky. How did the path from the mains through him and the tub come to be better than the path through the wires themselves? Unless he was two levels stupid and had modified the mains cable in some way.
It doesn't have to be easier, it just has to be present.
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Interesting would not think a 5vdc source would cause death, wonder if this only applies to cheap Chinese adapters that have no isolation.
According to the story the man rested a 240 V mains extension cable on his chest and then submerged it in the water. Nothing close to 5 V DC.
(It should be noted that he would have had to use a long extension cable to do this as UK electrical regulations do not permit mains sockets anywhere near a bathtub.)
Funnily enough, my bathroom is about 3.5m x 3.5m and there is a plug socket in the hallway <1m from the door to the bathroom. I can plug in my Macbook charger in the hallway and sit the laptop on a chair comfortably. Also, there are 120/240v supplies in bathrooms for shavers, but they should be isolated, as in most of the world.
Dumber than dirt, but also unlucky. How did the path from the mains through him and the tub come to be better than the path through the wires themselves? Unless he was two levels stupid and had modified the mains cable in some way.
Creates a voltage gradient. Electroboom has a video on this. And current doesn't take only the path of least resistance.
I'd like to know whether his bathplug was grounded though but even then he may not have had RCD protection.
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It's probably impossible to tell precisely what happened, the guy is dead so you can't ask him, and likely nobody was watching him bathe to witness the accident. He could have contacted a conductor with his hand while his lower half was immersed in the bath. Not a very good idea at any rate. This sort of accident was a lot more common back in the days of "hot chassis" AC/DC radios which was long before the GFCI/RCD existed.
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As is always the case, there is only ONE relivent fact in this case and the reporters seem to fail every time to clearly communicating this fact.
I.e. was it the phone or the extension/charger that was on his chest?
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As is always the case, there is only ONE relivent fact in this case and the reporters seem to fail every time to clearly communicating this fact.
I.e. was it the phone or the extension/charger that was on his chest?
Article writers may not know. So it could have been a dodgy, unsafe charger that had a live output referenced to the mains (no isolation/capacitive dropper/or just plain unsafe) or his charger cable was so short he rested an extension too close to the bath (or even rested it on his chest, which would corroborate the burns he sustained).
Water + directly to chest/heart + ignorance = Darwin award (unless he has kids then you have to feel sorry for them).
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I like how they're trying to blame Apple for this. This could have happened without the phone even being present. The phone just happened to be the device he wanted to charge but it could have been anything.
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Dumber than dirt, but also unlucky. How did the path from the mains through him and the tub come to be better than the path through the wires themselves? Unless he was two levels stupid and had modified the mains cable in some way.
If you have metal bath taps and copper piping then the bath taps are grounded. All you have to do is rest your toes on the faucet and you are dead in the water...
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I didn't read the article properly but I wouldn't rule out suicide too quickly. Often times the most impossible accidents happen on purpose.
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Was it his fault? Or maybe the fault of the English education system for not educating him on basic fundamentals of electrical safety?
We are all idiots. For example, when I was 19, I had one dim headlight on my car. I removed it, smashed it with a rock, went and bought another one, installed it, and it was still dim. The fault was a poor earth connection :palm:. But I learnt from my mistake :-DMM.
There is an old saying "fools never learn". Unfortunately with this bloke being electrocuted, he had no second chance. I think a mandatory primary school level education on basic electrical safety could have prevented his death.
I have known a number peer electronics engineers who have never received basic consumer education. They make the most stupid financial decisions. One being spending more than they earn on non-appreciating, non-essential assets over a long period of time, slowly going broke.
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I have known a number peer electronics engineers who have never received basic consumer education. They make the most stupid financial decisions. One being spending more than they earn on non-appreciating, non-essential assets over a long period of time, slowly going broke.
Probably the same problem we have over here. Throughout my education I don't remember one single class that more than touched on basic financial responsibility, credit, compounding interest, etc. When so many parents exhibit such poor financial behavior it's no wonder their kids make so many mistakes. Growing up without a lot of money wasn't always pleasant but I credit the experience with making me far more financially sensible than the average person. I've known so many people who make substantially more than I do yet are always broke.
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Was it his fault? Or maybe the fault of the English education system for not educating him on basic fundamentals of electrical safety?
I can't speak for his schooling. But I'm 33 and when I was at school we learnt a reasonable amount. Were even taught about voltage gradients such as having to keep your feet together insofar as if there was a felled overhead power line.
You cannot educate against ignorance, though! If he had the new iPhone 7, he may have thought that the phone is waterproof so he couldn't get shocked. You never know what goes through some people's minds.
The coroner isn't blaming Apple per se: I think the idea is to get Apple to make clearer electrical dangers so this, ideally, never happens again.
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It had to have been in some s--tty older property as all newer properties and rentals (and any older property where the insurance company has requested an electrical survey) will have had their consumer units replaced to provide RCD protection on all 'wet area' circuits. I'm not saying 30mA RCD protection would have been certain to save him but it certainly would have been a prettier corpse!
Given the likely age of the property it could well have been an enamelled cast iron bath, with a metal waste pipe.
Was it his fault? Or maybe the fault of the English education system for not educating him on basic fundamentals of electrical safety?
Educated in the UK in the '90s - 'nuff said!
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Lol. My US bathroom has a power outlet (They all do, every single on in the house) and they are all GFI sockets. So theoretically, if I were to plug something in and throw it into the tub, it would trip and turn off before it could kill me (Not gonna try that out)
They do sell some appliances here with GFIs on the chord or plug somewhere like hair driers and air conditioners.
But I believe in the notion that we should remove safety features so long as it's obvious to a person with reasonable common sense that there is a danger there, and let the people stupid enough to die from that shit get out of the genepool. Maybe that's a bit harsh.....
But seriously, it's in the same camp of the people who put their cat in the microwave and vote for Donald Trump burn themselves on hot food they just cooked.
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I think the idea is to get Apple to make clearer electrical dangers so this, ideally, never happens again.
It's not Apple's fault at all, nor their documentation. The guy plugged a mains extension cord into an outlet far away from the bathroom, brought it into the tub, and put the end of the extension cord on his chest while taking a bath. It doesn't matter what he plugged into it. Nothing Apple could have said would have prevented this guy from Darwining himself out of existence, that's just next-level stupid.
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Indeed. We end up with crap like this then:
(https://www.bitterwallet.com/media/images/2014/04/zzzw4.jpg)
:palm:
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I wonder if it could have beeen a low-voltage extension wire to the phone that was on his chest?
But the charger type was a cheap (Chinese) cap-dropper circuit with weird potentials to ground? And with no RCD device on the power-board to kill the circuit.
This guy explains cap-droppers,
A low voltage between two points in a circuit, DOES NOT mean that there is not a high voltage between one of those points and earth ground(you). The AC voltage across an LED may be a few volts while the AC voltage between either leg of that same LED and you could be dangerously high.
https://bobparadiso.com/2015/02/03/capacitive-dropper/
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Indeed. We end up with crap like this then:
(https://www.bitterwallet.com/media/images/2014/04/zzzw4.jpg)
:palm:
One would hope that the dumbest of dum f***'s would realise that a bag of peanuts contained peanuts.
Mind you I did once meet a young woman with a peanut allergy who had to be treated for anaphylaxis having eaten chicken in a satay sauce, knowing that the sauce contained peanuts because she "wanted to try something different" and "thought that she would be OK". |O
But I digress.
The bottom paragraph is not as daft as it looks. Peanuts are not, botanically speaking, nuts at all. They are legumes (the clue's in the "pea" bit).
Thus it is possible to be allergic to peanuts but not true nuts and vice versa. However peanuts are often handled on production lines which also process nut products and can get contaminated by nut dust - hence the warning that people with nut or sesame allergies (as well as those with peanut allergies) should not consume the product.
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This is another article on the subject. Its still not clear exactly what happened though. Phone chargers usually have a simple capacitor dropper rather than transformers. Yes it is only 5v output, but its still mains input and they are not usually earthed. One article suggests that the charger dipped into the water. If that was indeed the case and the water made contact with the mains inside the charger then due to lacl of earth there would have been no RCD protection. Assuming the residence has a consumer unit with RCD protection (older properties may not) then ironically, the extension socket falling in might have caused the RCD to trip and saved his life. Since these chargers are wall wart types that plug directly into the mains socket, Im not sure how you separate the charger unit from the mains extension so I would imagine one was plugged into the other and both were resting on his chest. A very dangerous thing to do indeed with saddly lethal consequences.
http://www.dailymail.co.uk/news/article-4322932/Man-32-dies-charging-iPhone-bath.html (http://www.dailymail.co.uk/news/article-4322932/Man-32-dies-charging-iPhone-bath.html)
PS regulation in the UK is that no mains sockets are allowed in a bathroom, only shaver socket. Lights must be operated from a cord switch rather than a wall switch. Its a safety measure to prevent wet hands or people sitting in baths from touching mains electrical inlets and switches or operating electrical appliances with possible electrocution risk. Its designed to prevent exactly this kind of situation and bypassing this using an extension lead is definitely not recommended.
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Phone chargers usually have a simple capacitor dropper rather than transformers.
Uuuhh, when was the last time you looked at a phone charger, 1995?
http://www.righto.com/2012/05/apple-iphone-charger-teardown-quality.html (http://www.righto.com/2012/05/apple-iphone-charger-teardown-quality.html)
http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html (http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html)
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As I said up thread, there can't have been a working RCD on that circuit. It would have tripped fast enough to prevent significant burns, and would probably have been fast enough to save his life.
UK trading standards are very tough on importers/sellers of fake chargers due to the lethal hazard of a mains PSU with insufficient or no isolation being used with a portable device and earbud headphones, so the odds are the victim got the end of the extension lead wet. If the live terminal of the socket had water in it but the neutral was still more or less dry, without a RCD, there would be up to 32A available (assuming a fake 13A plug fuse or other electrical dodgyness like a miswired socket) for a 'long pork' electric Wiener roast.
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http://www.dailymail.co.uk/news/article-4322932/Man-32-dies-charging-iPhone-bath.html (http://www.dailymail.co.uk/news/article-4322932/Man-32-dies-charging-iPhone-bath.html)
Quote from the deceased's brother in that article:
'We can all be careless at times, when you're younger you're taught about electricity and the bath but you don't think about it.
'I live in the US and they say it can't happen, and that there is not enough electricity. But in the UK it is enough. You don't think there is enough electricity but there is.
Is that really the prevailing thought in the US? Is that what is taught in school?
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What does apple have to do with it? Deep pockets? If you blame apple you have to blame:
The extention cord company
The water company
The electric company
The bath tub maker
The plumber who grounded the water pipe
The maker of the water pipe
The company that made the ground rob
The company that made the wiring in the house
The electrician who installed it
The maker of the outlet he plugged it into
The maker of the soap that made the water more conductive
And the list goes on.
Or you can be ignorant and mention the manufacture of the device like that has anything to do with being so stupid you kill yourself. Its not like electricity is some new invention that we are not used to and its not very well understood. In preschool you learn not to mix wet hands with outlets or cords.
I wonder what his IQ was. No doubt he had done this many times and got lucky.
Next story: "man gets run over as he doesn't look before crossing the street". The makers of the car were notified and its unclear whether Toyota is responsible.
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PS regulation in the UK is that no mains sockets are allowed in a bathroom, only shaver socket. Lights must be operated from a cord switch rather than a wall switch. Its a safety measure to prevent wet hands or people sitting in baths from touching mains electrical inlets and switches or operating electrical appliances with possible electrocution risk. Its designed to prevent exactly this kind of situation and bypassing this using an extension lead is definitely not recommended.
Also, this is incorrect.
Sockets are allowed so long as they are 3m outside of zone 1 (the area in which water is likely to get directly sprayed from a bath or shower). Light switches are allowed so long as they are outside of zone 2, which extends 600mm from zone 1.
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I think that rule is a bit stupid. In the US, as long as it's a GFI socket, you can put it in the bathroom.
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I have known a number peer electronics engineers who have never received basic consumer education. They make the most stupid financial decisions. One being spending more than they earn on non-appreciating, non-essential assets over a long period of time, slowly going broke.
Probably the same problem we have over here. Throughout my education I don't remember one single class that more than touched on basic financial responsibility, credit, compounding interest, etc. When so many parents exhibit such poor financial behavior it's no wonder their kids make so many mistakes. Growing up without a lot of money wasn't always pleasant but I credit the experience with making me far more financially sensible than the average person. I've known so many people who make substantially more than I do yet are always broke.
They dont teach any off that but over hear when I was a kid you pretty much got a 500$ capital one card on your 18th birthday and some how my brother got a $300 one when he was 17. I learned how credit worked because I wanted a new Preowned $34k BMW when I was 20. I got a loan. I did it through a complicated scheme of taking out multiple loans to get other loans paying them off with loans until I was 20 with a 700 mid fico credit score. My first car had 3.9%APR and was used. At one point (for first 3 months) the car payment was over 600$ a month but I could afford it since I had a job. Then 2008 happened and eight years and over 1000 on time payments went to shit in three months.
My father was a millionaire growing up but he told us we were poor, so we never got to enjoy it. Hes an hardware electrical engineer of course. But he would cheap out and end up paying more. But when every one got 600 bucks from GW Bush he got $65,000 back on his tax return. 600 bucks unless you are rich.
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...
My father was a millionaire growing up but he told us we were poor, so we never got to enjoy it. Hes an hardware electrical engineer of course. But he would cheap out and end up paying more. ...
IMO, there is a difference between false economy and being frugal. False economy equates to stupidity. I have seen some really stupid acts of false economy by a certain owner of a business - it has cost him very dearly, crippling the health of the business. Maybe like the electrocution guy, he does not even realise his lack of common sense will be his downfall. But being frugal can simply mean living below your means. Earn $100 every week and spend $105 every week, and you will eventually go bankrupt. But Earn $100 and spend $95, you will eventually grow rich. Earn $100 and spend $5, then you will die miserable.
Buying a luxury car when you are young, using money you don't have is a bad idea unless you want to attract pretentious chicks. You are better off with a cheaper car, like a Honda Civic which gets you from A to B that is reliable, than a face saving BMW or Mercedes. Even if I had $10 million in the bank, I would never be bothered with a luxury car. Anecdotally, people with humble cars tend to get better road respect from other drivers.
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Phone chargers usually have a simple capacitor dropper rather than transformers.
Uuuhh, when was the last time you looked at a phone charger, 1995?
http://www.righto.com/2012/05/apple-iphone-charger-teardown-quality.html (http://www.righto.com/2012/05/apple-iphone-charger-teardown-quality.html)
http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html (http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html)
In 1995 they would've probably been big linear transformers...
Not to say they don't exist, but bigclivedotcom on YouTube does teardowns of some very dodgy stuff, and he has yet to come across a capacitive dropper in a phone charger. (There's been some "surprise cap droppers" in PSUs that were not USB chargers, however.) The cheap Chinese manufacturers, although they don't always succeed, seem to at least try for an isolated design.
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What does apple have to do with it? Deep pockets? If you blame apple you have to blame:
The extention cord company
....<snip>...
The maker of the soap that made the water more conductive
And the list goes on.
Or you can be ignorant and mention the manufacture of the device like that has anything to do with being so stupid you kill yourself. Its not like electricity is some new invention that we are not used to and its not very well understood. In preschool you learn not to mix wet hands with outlets or cords.
I wonder what his IQ was. No doubt he had done this many times and got lucky.
Next story: "man gets run over as he doesn't look before crossing the street". The makers of the car were notified and its unclear whether Toyota is responsible.
Captain of his local Rugby club, and Rugby players are stereotyped the same way as American Football jocks. He may have been a MENSA member having a very bad day, but the odds are against it.
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Reminds me of when I spent a few months in China in the early 80's. At a lot of hotels, there would be a outlet at about bellybutton height in the side wall of the shower/tub, right in the middle. At 240V and no sign of a ground fault outlet, It was always scary to take a shower. I would cover the outlet in tape and divert the shower stream to hit the curtain and stayed to that side. Always be grateful for our NEC even though it seems not to make sense sometimes. Ah, the good ol days.
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Its always worth remembering the rest of the world does NOT have the standards for electrical safety we expect in 1st World countries, and the standards they do have are often only enforced if someone important gets killed. You don't need to go further afield than the average UK or US package holiday to find potentially lethal wiring if you stray from the resort hotels that have been checked by the tour operators.
e.g. https://www.eevblog.com/forum/projects/suicide-shower-hear-teardown/ (https://www.eevblog.com/forum/projects/suicide-shower-hear-teardown/)
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Its always worth remembering the rest of the world does NOT have the standards for electrical safety we expect in 1st World countries, and the standards they do have are often only enforced if someone important gets killed. You don't need to go further afield than the average UK or US package holiday to find potentially lethal wiring if you stray from the resort hotels that have been checked by the tour operators.
e.g. https://www.eevblog.com/forum/projects/suicide-shower-hear-teardown/ (https://www.eevblog.com/forum/projects/suicide-shower-hear-teardown/)
Those shower heads are freaking scary. Crazy to think they are a thing.
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'I live in the US and they say it can't happen, and that there is not enough electricity. But in the UK it is enough. You don't think there is enough electricity but there is.
Is that really the prevailing thought in the US? Is that what is taught in school?
I can assure you, it is not!!!! We were taught to respect electricity.
I think that rule is a bit stupid. In the US, as long as it's a GFI socket, you can put it in the bathroom.
That's the rule now. (I seem to vaguely recall that some jurisdictions now require the entire house to be on GFCIs.) In the past it wasn't, so in some very old installations you see unprotected outlets near water.
As a related tidbit, Switzerland historically didn't require GFCIs, even in wet areas, choosing instead to use recessed sockets in wet zones. Later GFCIs became mandatory (still with recessed sockets), and now, they're mandating recessed sockets everywhere, even outside wet zones.
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they're mandating recessed sockets everywhere, even outside wet zones.
That sounds like a pretty good idea. The US plug scares me, they NEVER stay fully inserted and the metal prongs are exposed for the full length of the plug. This means that within a couple of days of plugging something in, the plug will slightly back out and you'll have exposed metal at mains voltage just sitting there, waiting to cause problems.
I remember when I was young, I was playing around on my parents' bed and a metal pin (like a needle) fell behind the bed. There was a bang and a bright flash, and I ran out of the room yelling for my parents. Turns out there was an electrical outlet on that wall under the bed, and they had a lamp or something plugged into it. Naturally the plug had backed out a bit and exposed the metal prongs, and the pin just HAPPENED to fall horizontally right on those exposed pins, shorting them out. It coated the wall in black soot for about a 1' radius around the plug and could have easily started a fire. I've never been comfortable around the US plug since then. Recessing the plugs into the wall even a little bit would help out tremendously.
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That problem was solved on UK BS1363 plugs by sleeving the pins with no compromise on their current rating and little effect on their robustness. You'll also see sleeved pins on CEE 7/16 Europlugs (2 pin in flat body style), but they're only good for 2.5A max. Unfortunately blade pins aren't suitable for sleeving so the US doesn't get the easy fix that can be rolled out without changing all the sockets.
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Yea, the NEMAtoad plugs are pretty stupid. But there is a reason for them being the way they are. It's because a lot of early municipal electrical development occurred in the US at first (The plug was patented by Hubbell in 1913 while standards like the BS and CEE came into use after WW2) so while NEMA is one of the worst plug designs, it's also one of the oldest.
This is true for other things like NTSC. We came up, designed, and implemented NTSC before PAL was designed, which is why PAL is better as it was an improvement over the not as good NTSC standard.
Our customary measurements are based off of the Imperial system used by the UK (As we were previously colonies of the UK).
We haven't changed most of our standards because we both haven't had many wars fought on home turf, as parts of Europe had to rebuild and redesign after the world wars, while we sorta didn't need to, and because it as MUCH larger ordeal for us to change standards because we are so big in size and population. This IMO (Also based on some facts) is why we never really adopted the better and more worldwide standards like 240/230v power, PAL TV, and the Metric system.
And in terms of danger of 120v and 240v countries, keep in mind our outlets are current limited to 15A, which means, depending on other factors, we may be a bit more deadly. Then again, a standard German installation is 16A. The twice the voltage is not the end of the story. The alternation rates are different for all 120v countries (Except for half of Japan) than in 230/240v countries too.
But no matter how you put it, yes you can kill yourself on both if you ground yourself straight through your heart, and you're not within immediate medical care. If you ground yourself through your hand or arm, you might cause nerve and tissue damage, but it can't really kill you as easily.
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The AU plug has sleeved plate pins, and is rated for 10A, and is based on the US one, so it is possible to make a sleeved safer version of it.
NTSC is a standard that was devised to be both low cost to produce and reasonably robust, the colour added later to it was more meant to not interfere with the majority of monochrome sets and to give colour on newer sets. Thus the compromises in it, to have cheaper flyback ( the blanking period and why there is a front porch and a back porch, meant for cheap sets with minimal overscan not to have unwanted video on the sides of the older CRT displays), the unused lines top and bottom for the vertical retrace to be slower, the equalising pulses added so there was no DC component making it easy to have AC coupling throughout and thus no brightness shifts with drift, and the compromise on bandwidth making IF design easier. the original design was meant for tube sets, where each added tube was a good portion of the total manufacturing cost of the set, and higher frequency tubes were a lot more expensive to produce and required a lot more alignment and setup in production, along with much tighter design.
PAL used all the known issues with NTSC and designed around them, using the newer technology of transistors that were available in lowish cost at the time, so they could use a lot more in the set for a much lower cost, and still have a cheap reliable set.
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they're mandating recessed sockets everywhere, even outside wet zones.
That sounds like a pretty good idea. The US plug scares me, they NEVER stay fully inserted and the metal prongs are exposed for the full length of the plug. This means that within a couple of days of plugging something in, the plug will slightly back out and you'll have exposed metal at mains voltage just sitting there, waiting to cause problems.
I remember when I was young, I was playing around on my parents' bed and a metal pin (like a needle) fell behind the bed. There was a bang and a bright flash, and I ran out of the room yelling for my parents. Turns out there was an electrical outlet on that wall under the bed, and they had a lamp or something plugged into it. Naturally the plug had backed out a bit and exposed the metal prongs, and the pin just HAPPENED to fall horizontally right on those exposed pins, shorting them out. It coated the wall in black soot for about a 1' radius around the plug and could have easily started a fire. I've never been comfortable around the US plug since then. Recessing the plugs into the wall even a little bit would help out tremendously.
It would really make sense for the US to adopt sleeved prongs. As SeanB said, the Aussie plug uses almost identically sized prongs, and they require sleeving, so it's clearly possible.
As for the loose fit: I've found that this is usually due to outlets being old and worn out. Nobody does it, but the recommendation is to replace them every 10 years or so. Hospital-grade outlets grip plugs better, and don't loosen up with time. So in many ways, it's an implementation problem more than an inherent problem with the standard.
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I prefer the older outlets over the new ones, as the older ones at least used brass plate for the contacts, unlike the new ones which seem to be using something the thickness of bond paper, with some very small contact area to do the contact that is supposed to handle 16A. Then they use a switch that is made with such small contacts I would not trust them beyond 3A, but they have been certified. I have had to replace a number of 1 year old socket outlets that have either had the contacts weld themselves closed in the switch, had the switch melt closed or open or which have welded themselves to the plugtop inserted into them.
Load is 3kW, which is under 15A, but they failed with new sockets, so I went hunting for an unused older one instead after the third one.
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Wow I didn't know those shower heads even existed. We all have hot water heaters in the US. I'd be pretty nervous about using one especially in such bad repair. Would probably just be smelly until I could find a shower like the one at home. There is something similar now in the US, but it's nowhere near the bathroom. We're going from tanks to on demand systems that are much more efficient only heating water as it flows through a heating pipe, pretty nifty idea really. They simply replace existing tanks, far away from the bathroom fortunately.
Back to the original topic, I really can't believe anyone is that stupid to lay an extension cord outlet on his chest in the bath. Though no matter how impossibly stupid you think something is, there's always someone that's not past it. That's why you see these ridiculous warnings on products, like a bag of peanuts with a printed warning about peanuts. Like someone might think a bag of peanuts does not contain peanuts.
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The thing about the US plugs is they actually need the large contact area due to the high current and low voltage.
I've had an idea for a plug that is three rings each inside each other, with the middle ring being live, the next larger ring being neutral, and the largest ring being ground. This would allow for a VERY compact plug, it could be made out of sheet metal instead of other standards which require die pressing or other manufacturing standards. It could be designed with a twist lock connector that would turn on the power when locked, and only when locked. This means that you don't need to shutter or sleeve the outlets and plugs respectively, as it would require the plug to be fully inserted and twisted in order for power to be applied.
This would eliminate almost any and all problems with current standards
It would eliminate the bulk of the UK standard.
It would be polarized unlike the CEE standard
It would be better in every single way shape and respect to the NEMA standard.
I should probably make a good drawing of this, and I have posted this idea to the forum before.
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Fastest solution to fix US problems (most of them) would be to do it like in almost every EU country recess sockets by 1 cm and everyone is safe and happy :box: (applies to 3 pin sockets only, 2pin ones in US are just to loose like the ones in the red light district :-DD) and also ban 2 pin crap...
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The thing about the US plugs is they actually need the large contact area due to the high current and low voltage.
I've had an idea for a plug that is three rings each inside each other, with the middle ring being live, the next larger ring being neutral, and the largest ring being ground. This would allow for a VERY compact plug, it could be made out of sheet metal instead of other standards which require die pressing or other manufacturing standards. It could be designed with a twist lock connector that would turn on the power when locked, and only when locked. This means that you don't need to shutter or sleeve the outlets and plugs respectively, as it would require the plug to be fully inserted and twisted in order for power to be applied.
This would eliminate almost any and all problems with current standards
It would eliminate the bulk of the UK standard.
It would be polarized unlike the CEE standard
It would be better in every single way shape and respect to the NEMA standard.
I should probably make a good drawing of this, and I have posted this idea to the forum before.
The first thing I thought of when reading your description was powerCON...
http://www.neutrik.com/en/audio/powercon/ (http://www.neutrik.com/en/audio/powercon/)
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Fastest solution to fix US problems (most of them) would be to do it like in almost every EU country recess sockets by 1 cm and everyone is safe and happy :box: (applies to 3 pin sockets only, 2pin ones in US are just to loose like the ones in the red light district :-DD) and also ban 2 pin crap...
Not sure if you know what you're talking about, but our plugs aren't designed for a recess as they are NOT all the same size. Immediately all wall wart AC/DC converters will not fit anymore. Not to mention a change of this magnitude would be expensive. Any change in the US would be like asking over half of the European Union to change the standard.
The thing about the US plugs is they actually need the large contact area due to the high current and low voltage.
I've had an idea for a plug that is three rings each inside each other, with the middle ring being live, the next larger ring being neutral, and the largest ring being ground. This would allow for a VERY compact plug, it could be made out of sheet metal instead of other standards which require die pressing or other manufacturing standards. It could be designed with a twist lock connector that would turn on the power when locked, and only when locked. This means that you don't need to shutter or sleeve the outlets and plugs respectively, as it would require the plug to be fully inserted and twisted in order for power to be applied.
This would eliminate almost any and all problems with current standards
It would eliminate the bulk of the UK standard.
It would be polarized unlike the CEE standard
It would be better in every single way shape and respect to the NEMA standard.
I should probably make a good drawing of this, and I have posted this idea to the forum before.
The first thing I thought of when reading your description was powerCON...
http://www.neutrik.com/en/audio/powercon/ (http://www.neutrik.com/en/audio/powercon/)
That's not TOO far off. Maybe I can just rough napkin draw it, lemme get back to you.
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I've done a tad bit more than a napkin drawing and made a real quick 3D model using Roblox (Not the best 3D modeling tool, but it's the only one I know how to use)
I've exported it to OBJ, here it is.
https://www.dropbox.com/s/8awcejv99jgiuql/obj.zip?dl=1 (https://www.dropbox.com/s/8awcejv99jgiuql/obj.zip?dl=1) (Direct link)
Some pictures if you, like me, can't figure out what the hell to do with a 3D model:
http://prntscr.com/em2f03 (http://prntscr.com/em2f03)
http://prntscr.com/em2f26 (http://prntscr.com/em2f26)
http://prntscr.com/em2f4o (http://prntscr.com/em2f4o)
In order from smallest ring to largest ring, there is Live (In the direct center), Neutral (In the second largest ring), and Ground (The largest ring)
There is a plastic bump on the top that is supposed to insert into a notch in the socket, and when turned it would hit a microswitch and turn on the power. Two or more bumps/notches could be added for better locking and stability.
This way, the outlet wouldn't need a shutter, and the plug wouldn't need a sleeve. The power is off until the specially shaped notch is turned and hits a specially shaped microswitch in the socket. So you can stick whatever you want in the outlet, and won't get zapped.
The model isn't to scale by any means. I haven't done any real world measurements or anything, it's just to illustrate the concept.
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Tragic story, yes. But it could be worse. He could have been found in the bath with a mains wired breadboad on his chest and a Ben Heck video playing on the tele...
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This is another article on the subject. Its still not clear exactly what happened though.
http://www.dailymail.co.uk/news/article-4322932/Man-32-dies-charging-iPhone-bath.html (http://www.dailymail.co.uk/news/article-4322932/Man-32-dies-charging-iPhone-bath.html)
Key paragraphs:
, but the cable wasn't near the bath, it had been run there to charge a mobile phone.
'The extension cable was on the floor and it appeared as though he had his phone charger on his chest and the part between the phone charger and the cable had made contact with the water.'
Crappy writing style makes this less clear than it should, allow me to fix.
The extension cable was run across the floor and it appeared as though he had his phone charger on his chest and the join between the phone charger and the cable had made contact with the water.
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Its always worth remembering the rest of the world does NOT have the standards for electrical safety we expect in 1st World countries, and the standards they do have are often only enforced if someone important gets killed. You don't need to go further afield than the average UK or US package holiday to find potentially lethal wiring if you stray from the resort hotels that have been checked by the tour operators.
...
...
Even inside the USA, not all codes are followed at all places. Remember the Ghost Ship (warehouse) fire in Oakland, CA (Dec 2016). 36 died. The whole place with multiple floors of "residential areas" were powered by extension cords some originated from outside the building.
Some area in the USA, you have wires stringing overhead across streets totally illegally - but you can see they surely are in used to power kind-of homes.
There is a balance between the risk and the cost of avoiding the risk. When the cost of avoiding risk (implementing according to safety code) is too high, more and more will just ignore the code. Ghost Ship would not have existed if the cost of building an apartment is lower.
Most safety codes will add cost. Ghost ship was not a condemned building, but in Detroit MI and many other big cities, people are known to be living in condemned buildings. May be a less-safe but less costly set of regulations would end up saving more lives. Hard to say.
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I've done a tad bit more than a napkin drawing and made a real quick 3D model using Roblox (Not the best 3D modeling tool, but it's the only one I know how to use)
I've exported it to OBJ, here it is.
https://www.dropbox.com/s/8awcejv99jgiuql/obj.zip?dl=1 (https://www.dropbox.com/s/8awcejv99jgiuql/obj.zip?dl=1) (Direct link)
Some pictures if you, like me, can't figure out what the hell to do with a 3D model:
http://prntscr.com/em2f03 (http://prntscr.com/em2f03)
http://prntscr.com/em2f26 (http://prntscr.com/em2f26)
http://prntscr.com/em2f4o (http://prntscr.com/em2f4o)
In order from smallest ring to largest ring, there is Live (In the direct center), Neutral (In the second largest ring), and Ground (The largest ring)
There is a plastic bump on the top that is supposed to insert into a notch in the socket, and when turned it would hit a microswitch and turn on the power. Two or more bumps/notches could be added for better locking and stability.
This way, the outlet wouldn't need a shutter, and the plug wouldn't need a sleeve. The power is off until the specially shaped notch is turned and hits a specially shaped microswitch in the socket. So you can stick whatever you want in the outlet, and won't get zapped.
The model isn't to scale by any means. I haven't done any real world measurements or anything, it's just to illustrate the concept.
This adds a layer of safety, at the cost of redoing the world with a more complex design. And you still could argue that a shutter would make it still safer because the microswitch could conceivably fail closed.
While this thread is about someone who died in something that was probably related to standard power plugs, the existing designs, both US and European are obviously not terribly unsafe. The death rates are low. Even anecdotally related accidents with metal objects falling across improperly exposed pins didn't have lethal or even serious results. No argument that it couldn't have been worse, but the reality is that it wasn't, and isn't very often.
Perhaps the existing designs are good enough.
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This adds a layer of safety, at the cost of redoing the world with a more complex design. And you still could argue that a shutter would make it still safer because the microswitch could conceivably fail closed.
While this thread is about someone who died in something that was probably related to standard power plugs, the existing designs, both US and European are obviously not terribly unsafe. The death rates are low. Even anecdotally related accidents with metal objects falling across improperly exposed pins didn't have lethal or even serious results. No argument that it couldn't have been worse, but the reality is that it wasn't, and isn't very often.
Perhaps the existing designs are good enough.
My thoughts exactly. This seems like a very over-engineered design, a complex solution looking for a problem. While the US style plugs are probably some of the least safe in the developed world, it's not as though people are constantly electrocuting themselves just trying to plug stuff in. Most electrocutions are caused by people doing stupid things, case in point the incident that started the thread. Try to make something idiot proof and someone will find a better idiot. I don't even like the tamper resistant receptacles they require now for domestic use, they're expensive and only available in the crappy builder grade. It's difficult to get some plugs into them and even harder to probe with a multimeter or circuit tester. I can only imagine what a mechanically complex receptacle containing multiple microswitches would cost, not to mention the cost of adapters that would be needed for the decades long transition. I mean there are still millions of houses out there with ungrounded 2-prong receptacles and those have not been used in new construction in ~50 years.
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That definitely qualifies for a Darwin award.
I did find that odd when I visited the UK, no electrical outlets or switches anywhere in bathrooms, the only thing they did have was an isolated 110V shaver socket. Here in the US I don't think I've ever seen a bathroom that didn't have an outlet in it and most of the time the light switch is inside the bathroom too. Houses from the 1950s often have the bathroom light switch outside the door, something that amused me when I was about 4 years old turning the light off while someone was in there.
Getting slightly OT but I lived there in the 90's and could never quite get over the paranoia about not having power outlets in the bathroom and a cord pull switch for the light, but you could quite happily have a 240VAC mains powered instant shower in the shower cubicle :o
I thought they were the deathtraps......
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Tragic story, yes. But it could be worse. He could have been found in the bath with a mains wired breadboad on his chest and a Ben Heck video playing on the tele...
:-DD
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'The extension cable was on the floor and it appeared as though he had his phone charger on his chest and the part between the phone charger and the cable had made contact with the water.'
Crappy writing style makes this less clear than it should, allow me to fix.
The extension cable was run across the floor and it appeared as though he had his phone charger on his chest and the join between the phone charger and the cable had made contact with the water.
The media reports are somewhat fuzzy, but if the charger was on his chest, then a mains socket was on his chest. Maybe something like this:
(http://www.toobys.com/images/stories/virtuemart/product/TF1010.png)
If so, that would be insane. I guess there is a possibility that he had it balanced on the side of the bath, and it fell on him. Still quite an insane thing to do.
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He could not live without his phone for 5 minutes, and took chances playing with the grim reaper.
I'm just gonna leave this here:
(http://i169.photobucket.com/albums/u215/jdgilvin/Pool.jpg)
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The media reports are somewhat fuzzy, but if the charger was on his chest, then a mains socket was on his chest.
Not necessarily. Although the UK tabloid press is not known for their accuracy, in this case they may actually be reporting the facts. It is possible the extension lead socket was near but not in the bath. Many Apple chargers have a plug adapter for localisation, that connects to the main part of the charger via an IEC60320 C8 socket. A standard IEC60320 C7 (figure '8') mains lead will fit if the Apple plug adapter is removed.
@NANDBlog,
The consensus on the Snopes forum seems to be that the infamous pool + flipflops + extension lead photo was faked. http://message.snopes.com/showthread.php?t=24858 (http://message.snopes.com/showthread.php?t=24858)
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Interesting would not think a 5vdc source would cause death, wonder if this only applies to cheap Chinese adapters that have no isolation.
According to the story the man rested a 240 V mains extension cable on his chest and then submerged it in the water. Nothing close to 5 V DC.
(It should be noted that he would have had to use a long extension cable to do this as UK electrical regulations do not permit mains sockets anywhere near a bathtub.)
Oh yikes, I thought they meant the phone charger cable not the 240v one. Yeah that would pack a nice punch. :o
I'm going to assume Electrical Code is similar across North America since I'm from Canada... If you put an electrical socket anywhere within 3 feet of a water source it has to be a GFCI (Ground-Fault Circuit Interrupter) which has some sort of circuitry to detect if something has fallen into the water and kill the power presumably before it kills the person in question, this includes outlets outside the home as well as they get exposed to rain and such and have to go in their own special boxes to protect them. The GFCI outlets are also much more expensive like a regular outlet is (On par with an order of magnitude lol... $2-5 for a normal outlet and like $25-40 for a GFCI outlet). Anyways they'll look like this they have a test and reset switch right on them...
(https://upload.wikimedia.org/wikipedia/commons/9/9b/GFCIReceptacle.jpg)
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The posters on the Snopes message board don't appear to have electrical engineering knowledge to any greater degree than the muppets on the Craigslist message boards. It's not a truly reliable source of information, like, say, the Straight Dope.
As for GFCI sockets, they do not "detect if something has fallen in the water" and that is not their purpose. You can chop off a cordset, dangle it in the water, and plug it in to a GFCI and nothing will trigger it, unless the water has dissolved electrolytes.
As a qualifier to the above, the US type of GFCI can be triggered by dipping bare wires into a bathtub with a (grounded) metal drain. The wires need to be stripped so as to expose a fairly large area to the water; a chopped-off cord shows no response.
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The posters on the Snopes message board don't appear to have electrical engineering knowledge to any greater degree than the muppets on the Craigslist message boards. It's not a truly reliable source of information, like, say, the Straight Dope.
The combination of a set of photos showing the infamous pool + flipflops + extension lead being set up (you have to script a set of URLs for the photos as the directory listing is denied) + the distance from any of the buildings where the red lead could possibly be connected + the fact that the participants appear to be the teardown team after an IT event at the Northwood-LAN Frag Arena, and appear to be the right age range to be uni students, put the probability of fakery at 99.99%
As for GFCI sockets, they do not "detect if something has fallen in the water" and that is not their purpose. You can chop off a cordset, dangle it in the water, and plug it in to a GFCI and nothing will trigger it, unless the water has dissolved electrolytes.
As a qualifier to the above, the US type of GFCI can be triggered by dipping bare wires into a bathtub with a (grounded) metal drain. The wires need to be stripped so as to expose a fairly large area to the water; a chopped-off cord shows no response.
For GFCI a.k.a. RCD devices its all about current imbalance between live and neutral or for 240V US ones between L1, L2 and N considered as a set. European ones typically have trip current ratings of 10mA or 30mA, and the US seems to be fond of 5mA ones. Typically they will trip somewhere between 50% of the required current and the actual rating, so if your water conductivity, path length and exposed conductor area is low enough to keep the current under lets say 2mA, you can pass that current to ground all day without tripping.
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The posters on the Snopes message board don't appear to have electrical engineering knowledge to any greater degree than the muppets on the Craigslist message boards. It's not a truly reliable source of information, like, say, the Straight Dope.
The combination of a set of photos showing the infamous pool + flipflops + extension lead being set up (you have to script a set of URLs for the photos as the directory listing is denied) + the distance from any of the buildings where the red lead could possibly be connected + the fact that the participants appear to be the teardown team after an IT event at the Northwood-LAN Frag Arena, and appear to be the right age range to be uni students, put the probability of fakery at 99.99%
I would say you are a little low on your estimate of fakery. Look at the wires where they go over the edge of the pool. Looks like the two cords are taped together, not plugged into each other. Adds a level of safety to the end of the cord not shown in the picture not being plugged in. Protects against someone not involved in the joke helping out by plugging it in for them. Add that to the fact that there is no evidence of indicator lights on the radio or the power strips.
That said, I have lived in several parts of the country where people live out their lives emulating the "red neck" stereotype. I have seen things not too dissimilar to this in real life, propelled by the weekend case of beer , and everyone I was aware of survived. Fools apparently have guardian angels who protect them on a regular basis.
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This adds a layer of safety, at the cost of redoing the world with a more complex design. And you still could argue that a shutter would make it still safer because the microswitch could conceivably fail closed.
While this thread is about someone who died in something that was probably related to standard power plugs, the existing designs, both US and European are obviously not terribly unsafe. The death rates are low. Even anecdotally related accidents with metal objects falling across improperly exposed pins didn't have lethal or even serious results. No argument that it couldn't have been worse, but the reality is that it wasn't, and isn't very often.
Perhaps the existing designs are good enough.
My thoughts exactly. This seems like a very over-engineered design, a complex solution looking for a problem. While the US style plugs are probably some of the least safe in the developed world, it's not as though people are constantly electrocuting themselves just trying to plug stuff in. Most electrocutions are caused by people doing stupid things, case in point the incident that started the thread. Try to make something idiot proof and someone will find a better idiot. I don't even like the tamper resistant receptacles they require now for domestic use, they're expensive and only available in the crappy builder grade. It's difficult to get some plugs into them and even harder to probe with a multimeter or circuit tester. I can only imagine what a mechanically complex receptacle containing multiple microswitches would cost, not to mention the cost of adapters that would be needed for the decades long transition. I mean there are still millions of houses out there with ungrounded 2-prong receptacles and those have not been used in new construction in ~50 years.
Agree wholeheartedly. Most electrical incidents can be avoided with the exercise of a small amount of care and common sense. The suggested solution, while it may be effective in preventing inadvertent contact with mains voltage at plugs and receptacles, would be extremely expensive and take a very long time to implement and add considerably to the complexity of the receptacles with the associated increased potential for mechanical failure thereof. If people were being electrocuted left and right by the mains connectors used in the US, then something along these lines might be justified. Since that is not presently the case, it would instead be a huge added expense for, for all intents and purposes given the limited number of fatalities with the current system, barely any return.
-Pat
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If people were being electrocuted left and right by the mains connectors used in the US, then something along these lines might be justified. Since that is not presently the case
Very quickly acquired numbers:
Electrically-related workplace deaths in the USA, 2010: 160 (I excluded the lightning deaths, there were three.)
Electrically-related workplace deaths in the UK, 2010: 6.
That's about three times higher per capita. Seems to me there's substantial room for improvement.
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If people were being electrocuted left and right by the mains connectors used in the US, then something along these lines might be justified. Since that is not presently the case
Very quickly acquired numbers:
Electrically-related workplace deaths in the USA, 2010: 160 (I excluded the lightning deaths, there were three.)
Electrically-related workplace deaths in the UK, 2010: 6.
That's about three times higher per capita. Seems to me there's substantial room for improvement.
Well, that depends - were they all electrocuted by touching mains plugs, or were they perhaps electricians working on wiring? If the latter, then the mains plug design has nothing to do with it.
-Pat
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If people were being electrocuted left and right by the mains connectors used in the US, then something along these lines might be justified. Since that is not presently the case
Very quickly acquired numbers:
Electrically-related workplace deaths in the USA, 2010: 160 (I excluded the lightning deaths, there were three.)
Electrically-related workplace deaths in the UK, 2010: 6.
That's about three times higher per capita. Seems to me there's substantial room for improvement.
I'm not sure that workplace deaths is a good comparator because the health and safety elves will have more influence there which might mitigate unreliable design in the socket itself. H&S might also (possibly) have more influence in the UK than in the US.
This is 2010 data
http://www.electricalsafetyfirst.org.uk/what-we-do/policies-and-research/statistics/ (http://www.electricalsafetyfirst.org.uk/what-we-do/policies-and-research/statistics/)
But shows that there were 22 domestic deaths to 6 workplace deaths. Hard to say whether the home is more dangerous than the workplace per "person hour at risk" (or whatever, I just invented that) but it is a bigger number.
The more interesting figure is the number of non-fatal shocks which is reckoned to be 2.5 millionwith 350k serious injuries - I'd hazard the suggestion that finding comparable numbers for the 'states would be more illuminating.
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If people were being electrocuted left and right by the mains connectors used in the US, then something along these lines might be justified. Since that is not presently the case
Very quickly acquired numbers:
Electrically-related workplace deaths in the USA, 2010: 160 (I excluded the lightning deaths, there were three.)
Electrically-related workplace deaths in the UK, 2010: 6.
That's about three times higher per capita. Seems to me there's substantial room for improvement.
I'm not sure that workplace deaths is a good comparator because the health and safety elves will have more influence there which might mitigate unreliable design in the socket itself. H&S might also (possibly) have more influence in the UK than in the US.
It was just the first set of numbers I found.
The more interesting figure is the number of non-fatal shocks which is reckoned to be 2.5 millionwith 350k serious injuries - I'd hazard the suggestion that finding comparable numbers for the 'states would be more illuminating.
Non-fatal data is harder to come by and difficult to compare, as there's no requirement to record such data - deaths go down on a coroners report, not so much burnt fingers.
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If people were being electrocuted left and right by the mains connectors used in the US, then something along these lines might be justified. Since that is not presently the case
Very quickly acquired numbers:
Electrically-related workplace deaths in the USA, 2010: 160 (I excluded the lightning deaths, there were three.)
Electrically-related workplace deaths in the UK, 2010: 6.
That's about three times higher per capita. Seems to me there's substantial room for improvement.
I think it has to do everything with the plugs used in the USA. The first time I saw it in action, my reaction was this: :o The wiring code, the low voltage, the lack of grounding in too many equipment and plug... they all lead to problems like this. The strange thing, people go crazy when there is a plane accident in a decade, and let this ignorance kill many more people.
But you know, dont listen to the rest of the world, because, everything which is not a V8 4L car is a communist car.
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V8 4l is a little engine, you want at least 5.6l to have real power. If it gets more than 5MPG then it is eco friendly.
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I think it has to do everything with the plugs used in the USA. The first time I saw it in action, my reaction was this: :o The wiring code, the low voltage, the lack of grounding in too many equipment and plug... they all lead to problems like this. The strange thing, people go crazy when there is a plane accident in a decade, and let this ignorance kill many more people.
But you know, dont listen to the rest of the world, because, everything which is not a V8 4L car is a communist car.
That's an artifact of the way the human brain is wired. We have a natural tendency to tune out frequent things and focus greatly on unusual occurrences, at one point in time it likely had some evolutionary advantage. It's the same reason people fear shark attacks and school shootings while thinking nothing of getting into a 4,000 lb machine and getting on the highway after a few drinks or juggling their phone and a cheeseburger while driving.
The lack of grounding is a historical thing that has been going away but changes like this don't happen overnight. I really don't see the plugs as being a big issue, hundreds of millions of people use them every day and I've never known anyone who knew anyone who was electrocuted plugging in or unplugging something. I don't think I've ever even been shocked by handling a plug, I have been shocked a number of times but it was always doing something stupid, poking around inside live equipment, working on the wiring without shutting off the circuit, the typical "do as I say, not as I do" stuff that many of us here are likely guilty of.
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It was just the first set of numbers I found.
I appreciate that
The more interesting figure is the number of non-fatal shocks which is reckoned to be 2.5 millionwith 350k serious injuries - I'd hazard the suggestion that finding comparable numbers for the 'states would be more illuminating.
Non-fatal data is harder to come by and difficult to compare, as there's no requirement to record such data - deaths go down on a coroners report, not so much burnt fingers.
Nod, now that I think about it I wonder where "Electrical Safety First" got their data from - after all most people who suffer a non-fatal shock would just utter a few choice words and move on, not report it. I imagine it would not be beyond possibility that an electrical safety organisation might want to over-report the problem. >:D
The 350k could come from healthcare attendances though so might be more reliable.
I still think that looking at workplace fatalities is not that great a comparator. The number is small so going to be heavily affected by chance fluctuations and as I said one would hope that the workplace was actually "safer" than the home because safety of the workforce is supposed to be an employer's duty. Also, as Cubdriver pointed out there are likely to be more incidents related to installation or maintenance of electrical systems which would not say anything about the relative merits of the plug & socket.
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I think it has to do everything with the plugs used in the USA. The first time I saw it in action, my reaction was this: :o The wiring code, the low voltage, the lack of grounding in too many equipment and plug...
Given the sheer number of those plugs and receptacles in use across the US, combined with the number of total morons here, if being electrocuted by the NEMA 5-15 plug and its kin was an issue we'd be aware of it by now. ESPECIALLY if it were killing folks at a rate six times greater than in the UK. There are a lot of electrocutions in the US, but there is also a great deal of industry and construction, too, and you'll find that is where most of them happen. It's not people unplugging the vacuum cleaner and touching the prongs on the plug as they do so.
-Pat
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It's also still hard to get your fingers to touch the prongs as if you can fit your fingers behind the plug chances are it's not in far enough to get contact. McDonald's and fat fingers save lives! :-DD
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For those thinking about a safer power plug. Why not pull out all the stops. Add about four more contacts for low voltage power and signaling. Then your plug can report the VA requirements of your device, and the system can review the other loads on the circuit and decide if it is safe to power up. Maybe even have a priority rating for each device, so that if an urgent device is plugged in some lower priority device elsewhere would be turned off to make room for it. And then as long as you are at it, and already have some intelligence designed into the plug, add a relay in the downstream side, and some voltage sensing and your device can decide if it will accept the supplied power or refuse to turn on. Maybe a double relay system to eliminate the possibility of single point failures. There are lots of opportunities to put more belts and more suspenders on this thing.
No one should be satisfied with a power plug system that is not as safe as it possibly could be.
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Any level of safety can be retrofitted into out homes, workplaces, and electrical goods. All of the various types and methods to do so are available. The problem is what are you willing to pay for it? The more you protect, the more the cost and inconvenience. Your choice.
there is definitely a way to be able to run a electric grill in the middle of a pool on 240V with the cord and connectors laying IN the water. Hell you can make it safe with 50lbs of sodium chloride dissolved in the water. Again, what are you willing to pay for it?
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I like that three-ring design. The only thing that seems a little inelegant to me is that the two current-carrying contacts are substantially different sizes. A possible improvement could be to allow it to be plugged in in any orientation (well… maybe eight orientations), to make it easier to fit multiple wallwarts next to each other. This could be accomplished with a mechanical ring that accepts the locking nub and actuates the switch. Of course, there would be eight (or whatever number) nubs as well, for strength/redundancy.
For a while I have thought maybe we should analyze every plug design in common use worldwide as to advantages and disadvantages (electrical safety, foot safety, ease of manufacturing, cost, etc.) and design one with that knowledge to maximize the advantages and minimize the disadvantages.
[snip: TwoOfFive's design with the three rings and microswitch]
This adds a layer of safety, at the cost of redoing the world with a more complex design. And you still could argue that a shutter would make it still safer because the microswitch could conceivably fail closed.
The shutter could conceivably fail open.
(applies to 3 pin sockets only, 2pin ones in US are just to loose like the ones in the red light district :-DD)
As a member of /r/badwomensanatomy I am obligated to point out that vaginas do not get loose as a result of having sex many times or with many partners. That's already off-topic, though, so I'll let you all look that up on your own time if you don't believe it.
More on-topic, my school has some carrel desks (desks with dividers) in the hallways and library, which are equipped with outlets to plug in your laptop/phone/whatever. When I plug in my laptop (ungrounded), it's always so loose that the plug literally falls out of the outlet if I so much as brush the cord. Many of these outlets also don't provide power, for reasons unknown to me, so I bought one of those three-neon-lamp outlet testers to carry around and test them with before getting out my laptop and its power adapter and setting them up. I found that the tester, though, sticks very well in the outlets; it has a ground pin. I guess the outlets are cheap and their live and neutral contacts are worn out from everyone plugging in their ungrounded laptop and phone power adapters. I kind of want to get or make a 'reverse cheater plug' to leave on my laptop's cord to provide it with a ground pin that does nothing electrically, but helps it stay in the outlets.
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There are things you can do to make a plug fit tighter (and make better contact) in a loose socket. They are not really advisable since they often lead to sparks and smoke, and rarely to even worse things.
Complain to the school, pointing out the risk to their insurance costs and legal liability if a student is injured. It may motivate them to actually make repairs.
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Yea you could add more nubs to make it lock better. Maybe four, though, and have just one nub activate the microswitch.
I mean another reason why the NEMA standard is still used, it because it's INSANELY cheap.
https://goo.gl/LMGF7E
The cheapest one is 68 cents. I mean 68 cents, that is REALLY REALLY cheap. 100 outlets would be just 68 bucks, which is plenty for an entire house.
The advantage of mine is that you can make it cheap. The plug can just be looped sheet metal, and the outlet, which would require some plastic rings to insulate, could be something similar.
The reason I have designed it with neutral to be larger is then you have larger contacts for power going out than you do for power going in. It's really not needed, but hey, larger drain than tap means your sink doesn't overflow.
My design would also be very very small, which is an especially good thing compared to the British Standard which is MASSIVE. The rings would not need to be large, as the circular shape gives them a lot of surface area.
The outlets though, I think the best idea for contacts would be:
a pin in the middle for the live power
A plastic ring that would go around the live ring.
A metal ring that would go around previously mentioned plastic ring to make contact with the neutral ring
A plastic ring that would go around the neutral ring in the plug
And finally a metal ring that would go inside the ground ring to make contact with the ground ring.
Don't have time rn, but later I will make another 3D model.
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The cause of loose plugs is usually cheap receptacles. The contacts inside the cheap builder grade ones are just single wipe, flimsy metal, they wear and get loose over time. Get a good quality spec grade receptacle and it will have a very noticeably better feel. If you really want to go all out, hospital grade are the best you can get but they are much more expensive and the there are diminishing returns on the added expense.
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The reason I have designed it with neutral to be larger is then you have larger contacts for power going out than you do for power going in. It's really not needed, but hey, larger drain than tap means your sink doesn't overflow.
Are you sure it works that way? Think of what a GFCI/RCD detects.
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Lol, yeah, It's not really a justification, but it's more of a side effect of the design. You definitely don't want a live connection large then your return connection. Take for example, the NEMA 1-15 polarized standard. It has a larger return pin than live pin.
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Uhh, you might want to think about the concept of a circuit for a bit. All the current flowing out from one must (unless there is a fault condition) flow back in through the other. And though they're labeled as hot and neutral, since what's supplied is alternating current, it flows 'out' from each terminal alternately 60 times every second.
The wider return neutral pin is a relatively recent (40-50 yrs) thing and done strictly for polarization, nothing to do with current carrying capacity. Note that on a plug that also has a ground pin that both mains prongs are the same size - the ground pin provides polarization by only permitting the plug to be inserted in one orientation.
-Pat
<edit to change 'return' to the more correct 'neutral'>
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Um, yeah, the water analogy is often used for electricity because it's a reasonable approximation using a medium that one can actually see and touch, but it's far from a perfect analogy. Electricity doesn't pool when there is an insufficient return path. It can't overflow. It makes no difference if the live terminal is 10 times the size of the neutral or the other way around, the current is always exactly the same on both. When dealing with AC the terms live and neutral are really rather meaningless anyway since the polarity changes every half cycle. The only thing it does tell you is that neutral (hopefully) shares the same potential as the ground you are standing on.
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Lol, yeah, It's not really a justification, but it's more of a side effect of the design. You definitely don't want a live connection large then your return connection. Take for example, the NEMA 1-15 polarized standard. It has a larger return pin than live pin.
Why don't you? What will it do, make something catch fire?
It really doesn't matter what size the pin is so long as it's big enough. They don't have to match in any way.
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Not to mention most grounded NEMA 15 plugs do not have a wider neutral prong, the prongs are the same size since the ground prong prevents plugging it in backwards.
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I see all this and then I remember it was only 30 years ago my nan was regularly tucking herself into bed, plugging her electric blanket into an extension lead hanging from the light fitting and lighting a final cigarette before drifting to sleep with it hanging out of her mouth on her nylon nightdress. Before bed she's sit there and watch her black and white valve TV which she'd replaced the fuse with some copper flex core curled up in a ball. If it was a cold night she'd leave the gas oven on in the kitchen with all the windows shut for a couple of hours before bed to heat the place up.
The woman was a life's education in a few minutes.
Fundamentally, whatever you build, the idiots will come.
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Reminds me of when I'd walk to the nearby lawnmower repair shop to buy parts when I was a teenager, I'd frequently see one of the old guys who worked there pouring gas (petrol) out of something he was working on into a jug with a lighted cigarette dangling from his mouth. Always surprises me when I see someone like that actually make it to as old as he was.
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Tragic story, yes. But it could be worse. He could have been found in the bath with a mains wired breadboad on his chest and a Ben Heck video playing on the tele...
:-DD
Does anyone else feel bad for that guy? He must have a terrible time getting laid. Looks like he got over his speech impediment pretty well. He almost looks like hes straight out of an episode of the simpsons. At least hes smart.
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There is, however, a valid reason for neutral to be smaller than live in NEMA 1-15: It's slightly easier to jam a metal tool into the neutral slot than the live slot, or, more importantly, it's slightly harder to jam a metal tool into the live slot than the neutral slot. Therefore, if one has to be larger for polarization or other mechanical reasons (such as the three-ring design), it should be the neutral.
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I can't help but find it a bit ironic that in a thread discussing ignorance of electrical safety there's talk about the continued use of mains sockets that are so loose the plug falls out ??? :palm:
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There's an easy fix for most of the issues with NEMA 1-15 - simply complete phasing it out. You already cant install new NEMA 1-15 outlets, so ban the NEMA 1-15 two pin plug on new equipment or as a retail item, and introduce a requirement for all new NEMA 5-15 outlets, extension cords etc. to have shutters for the line and neutral, opened by the ground pin (an improvement to the existing tamper resistant requirements in many states) and a label prohibiting 2 pin plugs, and tighten up the requirements for retention force.
Of course that doesn't help with the unshrouded pins issue, but with only 0.06" blade thickness to work with, its difficult to shroud the pins without increasing the risk of them breaking off in the socket.
With the average life of modern electrical goods being as low as it is, and the gradual reduction is sockets that would accept them, that could remove half the NEMA 1-15 plugs from consumers within five years, rising to 9/10 within ten years
Some concessions may be needed for repair parts sold only to a licensed electrician, with a sizeable fine if they are resold other than as parts used during a repair, and rewards for reporting contraventions funded by the fines.
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A similar process could see 240V outlets deployed for use with modern equipment with switching supplies - nearly all of which is designed for 240V operation and measurably more efficient there. 2-3% doesn't sound like much, but it's entire power plants..
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A simple code requirement that all new 120V outlets must be within 1 yard of a 240V outlet and the number of 120V outlets in a room must not exceed the number of 240V outlets could do that, but IMHO that's a step too far. Maybe just slap a tax on 120V plugs and outlets?
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I can't help but find it a bit ironic that in a thread discussing ignorance of electrical safety there's talk about the continued use of mains sockets that are so loose the plug falls out ??? :palm:
We must have been reading different threads, because in this one, the advice continues to be "replace loose receptacles with new ones".
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... tighten up the requirements for retention force.
A truly sensible suggestion, but absent data showing real hazard from loose sockets (like fires and electrocution), not just inconvenience, it's never gonna happen. :(
Of course that doesn't help with the unshrouded pins issue, but with only 0.06" blade thickness to work with, its difficult to shroud the pins without increasing the risk of them breaking off in the socket.
We don't have to speculate on this: Australia uses sheathed blades that are almost identical in dimension to NEMA blades. If there isn't already data on this, at minimum we have actual mass-produced product we could put through testing to find out if this is actually a problem or not. (My guess is that since they've been widespread in Australia for a decade IIRC, if they were problematic, we'd know about it already.)
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Not sure if true or trolling, but:
(https://i.imgur.com/IKfNJE7.jpg)
:P :P :P
Alexander.
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Yeah, that was already posted earlier in this thread...
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@firewalker,
NANDblog posted that in reply #60 (https://www.eevblog.com/forum/chat/man-dies-charging-phone-in-the-bath/msg1165372/#msg1165372). Its been debunked as a hoax set up by an IT convention setup/teardown crew.
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(https://www.eevblog.com/forum/chat/man-dies-charging-phone-in-the-bath/?action=dlattach;attach=302791;image)
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<ROTFLMAO> :-DD
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There's an easy fix for most of the issues with NEMA 1-15 - simply complete phasing it out. You already cant install new NEMA 1-15 outlets, so ban the NEMA 1-15 two pin plug on new equipment or as a retail item, and introduce a requirement for all new NEMA 5-15 outlets, extension cords etc. to have shutters for the line and neutral, opened by the ground pin (an improvement to the existing tamper resistant requirements in many states) and a label prohibiting 2 pin plugs, and tighten up the requirements for retention force.
Of course that doesn't help with the unshrouded pins issue, but with only 0.06" blade thickness to work with, its difficult to shroud the pins without increasing the risk of them breaking off in the socket.
With the average life of modern electrical goods being as low as it is, and the gradual reduction is sockets that would accept them, that could remove half the NEMA 1-15 plugs from consumers within five years, rising to 9/10 within ten years
Some concessions may be needed for repair parts sold only to a licensed electrician, with a sizeable fine if they are resold other than as parts used during a repair, and rewards for reporting contraventions funded by the fines.
You sound like a person who has never lived a year in the US.
Our plugs aren't falling out like crazy, and they hold in fine enough. If you're not a dumbass, you can live your life without a single electrical issue. There are also plugs that are WAY too tight. I have a UPS that is by design, incredibly tight on the plugs. You have to REALLY pull to get it out.
NEMA 1-15 and 5-15 on plugs are interchangeable. We don't need a ban on 1-15 plugs, that would probably just piss people off. We also REQUIRE shutters on our sockets on new installations that are opened by the top two sockets, although I have never seen this.
The US standard is gonna stay. We've had it for almost 100 years now, and it doesn't cause enough harm to people in order to replace the standard.
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One thing I hate is how lot of electrical items such as timers still have only 2 prongs. How hard is it to add the ground, really? It just makes it harder to plug stuff like a power bar when it's only 2 prong. One thing that would be nice to see for those situations though is a 2 prong to 3 prong converter, it could simply consist of a GFCI. It would provide some level of protection even though there is no real ground. I made my own so I can plug a power bar in a Christmas light timer for my tree and other lights, but it's much more bulky than something that could be manufactured in a small plug like device.
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There are cheater plugs that have a ground tag hanging out. You're supposed to connect the tag to something like a radiator or vent, or some other large piece of grounded metal (Taps, ovens, etc.) but often people forget this (I have walked into my great grandmother's basement before and have seen florescent tube lights connected to like really wimpy 1970's NEMA 1-15 extension cables with the ground just off to the side)
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(US) appliances expected to be used in a wet environment, like hairdryers, pressure washers, or shop vacs, have GFCIs built into the cord to provide extra safety, with or without being grounded to the outlet.
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Both the timer and the RF remote outlet I use to control outdoor decorations have grounded connections all the way through (plug and socket) as well as having protective covers to keep the wet out (though I use them on my porch, and if they seriously get wet back against the house, we are having the storm of the century).
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The advantage of mine is that you can make it cheap. The plug can just be looped sheet metal, and the outlet, which would require some plastic rings to insulate, could be something similar.
Funny thing is, there is a standard, the entire world is using for power. It is finger proof, smart, small and reliable. Millions of equipment is using it, in every single country.
I'm talking about the IEC 60320 plugs of course. A power strip with IEC E or C plugs woutl be fraction of the size of what we have. Look at this:
(http://uk.farnell.com/productimages/standard/en_GB/269190-40.jpg)
It is simple, elegant, compatible with everything.
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The advantage of mine is that you can make it cheap. The plug can just be looped sheet metal, and the outlet, which would require some plastic rings to insulate, could be something similar.
Funny thing is, there is a standard, the entire world is using for power. It is finger proof, smart, small and reliable. Millions of equipment is using it, in every single country.
I'm talking about the IEC 60320 plugs of course. A power strip with IEC E or C plugs woutl be fraction of the size of what we have. Look at this:
http://uk.farnell.com/productimages/standard/en_GB/269190-40.jpg (http://uk.farnell.com/productimages/standard/en_GB/269190-40.jpg)
It is simple, elegant, compatible with everything.
And it's even available with shutters!
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That would be too easy! I mean people can already buy adapters from all of the worlds standards to IEC. Where is the pain in that?
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That would be too easy! I mean people can already buy adapters from all of the worlds standards to IEC. Where is the pain in that?
I tend to think the incompatible plug standards at least makes people think a bit about frequency/voltage before plugging stuff in. I have fond memories of my Aunt coming over from California in the 80's and plugging her hair dryer in using a straight adapter. It didn't appear to be very happy about running at over double the voltage (we were 250V back then).
At least the act of having to use an adapter has prompted many a "is this going to be ok?" questions.
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That would be too easy! I mean people can already buy adapters from all of the worlds standards to IEC. Where is the pain in that?
I tend to think the incompatible plug standards at least makes people think a bit about frequency/voltage before plugging stuff in. I have fond memories of my Aunt coming over from California in the 80's and plugging her hair dryer in using a straight adapter. It didn't appear to be very happy about running at over double the voltage (we were 250V back then).
At least the act of having to use an adapter has prompted many a "is this going to be ok?" questions.
With the attitude of many I have seen on this thread there also an easy solution for that problem. Just mandate that all equipment be designed to accept everything from 45-75 Hz and 90 to 270 volts. Means a few extra parts and some more volume, but what the heck. Maybe a little hit in efficiency, but who cares about that outside of tree huggers. Oh, and none of that stuff that requires setting a switch or jumper like much current test gear. Full automatic detection and changeover as required.
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That would be too easy! I mean people can already buy adapters from all of the worlds standards to IEC. Where is the pain in that?
I tend to think the incompatible plug standards at least makes people think a bit about frequency/voltage before plugging stuff in. I have fond memories of my Aunt coming over from California in the 80's and plugging her hair dryer in using a straight adapter. It didn't appear to be very happy about running at over double the voltage (we were 250V back then).
At least the act of having to use an adapter has prompted many a "is this going to be ok?" questions.
With the attitude of many I have seen on this thread there also an easy solution for that problem. Just mandate that all equipment be designed to accept everything from 45-75 Hz and 90 to 270 volts. Means a few extra parts and some more volume, but what the heck.
What, you mean like pretty much every <1.5kW SMPS not made solely for the US market already does?
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What, you mean like pretty much every <1.5kW SMPS not made solely for the US market already does?
Which is cool if your device is electronic. Things like motorized appliances (blenders, hair dryers, drills, grinders), heating appliances (hair dryers, heat guns, soldering irons)... well another story perhaps.
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Funny thing is, there is a standard, the entire world is using for power. It is finger proof, smart, small and reliable. Millions of equipment is using it, in every single country.
I'm talking about the IEC 60320 plugs of course. A power strip with IEC E or C plugs woutl be fraction of the size of what we have. Look at this:
http://uk.farnell.com/productimages/standard/en_GB/269190-40.jpg (http://uk.farnell.com/productimages/standard/en_GB/269190-40.jpg)
It is simple, elegant, compatible with everything.
I didn't realize there are power strips like that. Must get some for my "lab" NOW!
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What, you mean like pretty much every <1.5kW SMPS not made solely for the US market already does?
Which is cool if your device is electronic. Things like motorized appliances (blenders, hair dryers, drills, grinders), heating appliances (hair dryers, heat guns, soldering irons)... well another story perhaps.
Anything which actually has a voltage dependence is, of course, another story. But a lot of stuff doesn't (soldering irons? Really? They don't have to be fixed voltage or even selectable, you can drive them purely switch mode and it's not even expensive.. mine doesn't even have a heating element).
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What, you mean like pretty much every <1.5kW SMPS not made solely for the US market already does?
Which is cool if your device is electronic. Things like motorized appliances (blenders, hair dryers, drills, grinders), heating appliances (hair dryers, heat guns, soldering irons)... well another story perhaps.
Which one of these are you carrying from a 110V country to a 230V one? I cannot imagine someone putting a blender in the check in baggage.
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What, you mean like pretty much every <1.5kW SMPS not made solely for the US market already does?
Which is cool if your device is electronic. Things like motorized appliances (blenders, hair dryers, drills, grinders), heating appliances (hair dryers, heat guns, soldering irons)... well another story perhaps.
Which one of these are you carrying from a 110V country to a 230V one? I cannot imagine someone putting a blender in the check in baggage.
Problem is not taking necessities when traveling, but buying stuff from other countries especially from US and hopping that it will work in EU, AU,NZ and so on and vice versa.
Also while we are on this topic, this situation is fu**ed up, I'm traveling to US from time to time, thus I had to buy new shaver because mine had trafo in the "brick" and hotel room did not have 220 socket in the bathroom or it was broken all the time.....
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What, you mean like pretty much every <1.5kW SMPS not made solely for the US market already does?
Which is cool if your device is electronic. Things like motorized appliances (blenders, hair dryers, drills, grinders), heating appliances (hair dryers, heat guns, soldering irons)... well another story perhaps.
Which one of these are you carrying from a 110V country to a 230V one? I cannot imagine someone putting a blender in the check in baggage.
Hair dryer, which was a specific example given previously of a device that someone wanted to use on 250v.
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It's not fair that extension leads aren't allowed in the bathroom, how else am I supposed to make bath toast or shower coffee?
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And they're at it again |O
At least this person survived, so be it with some odd burns.
http://www.theage.com.au/technology/technology-news/man-nearly-electrocuted-after-falling-asleep-with-his-iphone-charging-in-bed-20170402-gvc2dv.html (http://www.theage.com.au/technology/technology-news/man-nearly-electrocuted-after-falling-asleep-with-his-iphone-charging-in-bed-20170402-gvc2dv.html)
The next morning, Day woke up and rolled over. As he did so, a dog-tag necklace that he was wearing happened to catch on the exposed prongs of the charger head, which had come loose from the extension cord.
The metal chain suddenly became a conductor for the electricity - and it travelled straight to Day's neck.
His niece alerted him to a sign of what had happened: There was smoke coming out of the extension cord.
Day's shirt was singed, with a small hole burned out. There were strips of skin and flesh missing where the metal chain had scorched his neck. And the pattern of the necklace was burned into parts of his hands where he had gripped the chain to try to tear it off.
Oh boy, he turned the chain around his neck into an electric heater.
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What, you mean like pretty much every <1.5kW SMPS not made solely for the US market already does?
Which is cool if your device is electronic. Things like motorized appliances (blenders, hair dryers, drills, grinders), heating appliances (hair dryers, heat guns, soldering irons)... well another story perhaps.
Which one of these are you carrying from a 110V country to a 230V one? I cannot imagine someone putting a blender in the check in baggage.
Don't laugh.
Once when working behind the retail counter, I had someone tell me they had moved from the USA to Australia and brought several appliances with them. Some of them worked fine - but then they told me of one in particular. A vacuum cleaner. Using the "appropriate" adapter, it apparently worked REALLY TERRIFICALLY ... for nearly two weeks before it collapsed into a smoking heap. A couple of minutes of explanation and telling them what to look for and they went on their merry way. It was a productive discussion, because they were able to comprehend the basics.
A month or so later they came into the shop again and I was pleased to hear they had not encountered any more problems - but they did ditch a couple of other appliances and bought new ones locally.