Why does a phone charger have lethal voltage on its case?

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Sockets are rare in UK bathrooms but some houses have a socket for a washing machine in the bathroom. In my part of the UK there is a trend towards building more three storey houses in order to cram more into a given area of land. This makes it more annoying to have to carry washing up an down stairs so it makes more sense for the washing machine to go in the bathroom on the middle floor rather than in the kitchen on the ground floor.
 
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Guineafowl said:
if you need an electric bathroom heater, upgrade your heating system.
Central heating is not always a Green Solution. If you visit a room twice a day then why keep it heated to a (wet naked body) temperature all day? As a Scotsperson you will be aware of the importance of domestic economy. (As a mere Englishperson - I had to learn this myself, without cultural help and to be 'careful' with my money :wink:)
Lifestyles vary and watching the TV from the bath is quite an attractive idea. I know that many people have a TV on in the background almost 24/7 so why have it different in the bathroom? Personally, I tend to have a radio on for most of the time and I have a 9V lead, feeding my transistor radio in the bathroom. I would use batteries but a DRB receiver eats them up too fast. I cannot reach it from the bath so I reckon I am safe.
 
sophiecentaur said:
Central heating is not always a Green Solution. If you visit a room twice a day then why keep it heated to a (wet naked body) temperature all day? As a Scotsperson you will be aware of the importance of domestic economy. (As a mere Englishperson - I had to learn this myself, without cultural help and to be 'careful' with my money :wink:)
Lifestyles vary and watching the TV from the bath is quite an attractive idea. I know that many people have a TV on in the background almost 24/7 so why have it different in the bathroom? Personally, I tend to have a radio on for most of the time and I have a 9V lead, feeding my transistor radio in the bathroom. I would use batteries but a DRB receiver eats them up too fast. I cannot reach it from the bath so I reckon I am safe.
Getting a little off topic (!), but to heat a 'wet' room only when you're in there, then let it get quite cold the rest of the time is inviting damp problems. In Scotland, we know about damp, but also about cold - it is better, IMHO, to heat the house evenly at a low level that is comfortable, than to have the heating off and on in a binary fashion.

"Lifestyles vary" - indeed. I suppose it comes down to whether you regard bathing (etc) as a leisure activity or just a necessity. I find it a damned nuisance, a chore, and envy the dog - he just gets up, tiddles in the bushes and is ready for the day. For me, the lowest possible dwell time in the bathroom is best, and having entertainment devices in there would only increase that. Each to their own, though!
 
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Guineafowl said:
For me, the lowest possible dwell time in the bathroom is best,
No scented candles and whale songs for you then?
An extractor fan with hygrostat is a cheaper solution than heat.
 
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Today's news contains photos of the frayed extension cord that electrocuted the girl.

Let's examine the safety engineering lessons to be learned from this thread. The safety engineer does:
  1. Start with physics and ohm's law.
  2. Add biology (lethality of shocks)
  3. Add non-standard failure modes (a frayed cord). Hundreds of failure mode scenarios are possible.
  4. Add human behavior. If there is no socket in the bathroom (a) Users will dry their hair and charge their phones in other rooms, enhancing safety. OR (b) Users will run extension cords from other rooms (as this girl did), decreasing safety.
It is easy to see how different jurisdictions might produce safety codes where one makes a bathroom socket mandatory and another jurisdiction forbids them. Both conclusions might be right and proper if they correctly forecast the behavior of local people. But it bewilders outsiders who can't understand why they are so different; especially if the outsiders are interested only in step 1 of the process (the physics.)

Now let's examine the dynamics of international public forums like PF. That is a separate subject that interests me.
  1. The thread started with posters curious about the safety implications of a set of facts reported in the press. That set of facts turned out to be false. The discussion has meandered and drifted far far away from the original question. Sometimes, the mentors cut us off for doing that, sometimes not.
  2. Any person jumping in now, is not likely to read the entire history of this thread. The longer the thread (# of posts) the more difficult it becomes to stay on-topic. I am fond of what @Dale once said that the best answer is often given in post #2 and threads go downhill from there.
  3. This is a casual conversation. We all offer opinions without a rigorous and comprehensive agreement about what subject we are commenting on. If this were a formal international conference, much boring groundwork would be necessary to make sure that all participants are on the same page regarding the topic before anyone offers opinions about anything.
  4. We all bring our local experiences, local customs and local assumptions to the table. But we have only vague or zero knowledge about the localities of other participants in the conversation.
  5. We know absolutely nothing about this thread's lurkers, now or in the future. We don't know how many. We don't know their backgrounds. It is hard to remember that they even exist.
  6. Despite all those handicaps, we enjoy doing it and we usually manage to learn something from it beyond post #2. Long live PF.
 
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A nice round-up of the thread, @anorlunda . We have indeed drifted off-topic a little! Just one more thing...

anorlunda said:
Add human behavior. If there is no socket in the bathroom (a) Users will dry their hair and charge their phones in other rooms, enhancing safety. OR (b) Users will run extension cords from other rooms (as this girl did), decreasing safety.

Most people would champion their country's way of doing things, I admit. What you grow up with becomes 'what is right'. The lack of sockets in UK bathrooms can be defeated by an extension cord, yes, but I think that same lack reinforces the idea that mains power in a watery room can be dangerous. So we are discouraged from using an extension cord by that mental conditioning.

Mention using an electric heater on a cord into a bathroom and most here would give a little intake of breath (you know, the 'experts' propping up the bar). You may have rigged it fairly safely but there's always that little mental flag. If it's OK to use mains in the bathroom then why do you never see a socket in there?

On the other hand, I suppose it might be nice to have a radio in there. The morning bathroom routine is so boring...
 
Guineafowl said:
The morning bathroom routine is so boring...
The BBC Radio 4 'Today' prog lifts the gloom. But they seldom mention matters a long way from London (except to knock the SNP or Mr Trump).
 
Guineafowl said:
but I think that same lack reinforces the idea that mains power in a watery room can be dangerous.

True, but stretch your imagination further. Not everyone lives in a house. Not everyone has walled-off areas that you could call rooms.

I have those differences fresh in mind because I just finished 12 years living on a small boat, and I have moved from there to an RV (you might call it a caravan) that has some house-like features but not all.

People who read this post on PF can be very diverse culturally.
 
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anorlunda said:
Today's news contains photos of the frayed extension cord that electrocuted the girl.

Let's examine the safety engineering lessons to be learned from this thread...
Great wrap-up.
Now let's examine the dynamics of international public forums like PF. That is a separate subject that interests me.
  1. The thread started with posters curious about the safety implications of a set of facts reported in the press. That set of facts turned out to be false. The discussion has meandered and drifted far far away from the original question. Sometimes, the mentors cut us off for doing that, sometimes not.
  2. Any person jumping in now, is not likely to read the entire history of this thread. The longer the thread (# of posts) the more difficult it becomes to stay on-topic. I am fond of what @Dale once said that the best answer is often given in post #2 and threads go downhill from there.
  3. This is a casual conversation. We all offer opinions without a rigorous and comprehensive agreement about what subject we are commenting on. If this were a formal international conference, much boring groundwork would be necessary to make sure that all participants are on the same page regarding the topic before anyone offers opinions about anything.
  4. We all bring our local experiences, local customs and local assumptions to the table. But we have only vague or zero knowledge about the localities of other participants in the conversation.
  5. We know absolutely nothing about this thread's lurkers, now or in the future. We don't know how many. We don't know their backgrounds. It is hard to remember that they even exist.
  6. Despite all those handicaps, we enjoy doing it and we usually manage to learn something from it beyond post #2. Long live PF.
Great extension. And as a moderator, I will acknowledge a) not having checked-in on the thread for a few days and b) that I probably wouldn't have tried to steer the thread back on topic or lock it if I had. As you correctly pointed out in post #2, we didn't have enough information, and that's a recipe for a meandering thread. But at the same time, much of the speculation/discussion was valuable and it kept the thread in view until the media hype died-down and the much simpler truth came out.

Long live PF!
 
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Being a resident of Texas, I can verify the following. First, not all bathroom outlets have GFCI, in spite of regulations to the contrary. Secondly, she may have submerged both her hand, and the phone, since electrical safety has never been a major priority in this area. Beyond that, she could have had a 'generic' phone charger, of almost any manufacture, but her parents would have denied that, for reasons of liability. Finally, exactly what occurred, and why, will never be known, as there is a suit for wrongful death in the works, and the story will conform to whatever the lawyer suggests. It's probably tragic, but the truth will remain hidden.
 
Victor Ray Rutledge said:
Being a resident of Texas, I can verify the following. First, not all bathroom outlets have GFCI, in spite of regulations to the contrary.
Note that some may have GFCI and not realize it. My house has an odd "house GFCI" circuit, which appears to be based on one GFCI receptacle in the garage wired in series with the rest of the "wet" receptacles (3 bathrooms, 2 outside).
 
russ_watters said:
Note that some may have GFCI and not realize it. My house has an odd "house GFCI" circuit, which appears to be based on one GFCI receptacle in the garage wired in series with the rest of the "wet" receptacles (3 bathrooms, 2 outside).
Yep. I have one in the bathroom that's also wired to an outside receptacle.
 
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Just to confirm some points regarding UK & european bathroom fittings. In the UK there are no wall mounted switches allowed, the only switch approved for bathrooms is a ceiling mounted switch operated by a cord hanging down from it to operate the light. There are some wet area approved ceiling heaters using radiant or infra red heating, again only operable using a pull cord. The only normal wall switch used in a bathroom is for an immersion heater but that switch is located inside the cupboard covering the hot water tank so not exposed to water. Also sockets in UK are really protected as the + & - connectors are covered until the Earth Connector is inserted then the other terminals are then open to receive the plus and minus pins.

In Europe, 220v wall sockets and light switches are used in bathrooms but sockets have to be at least 50cm away from any water source.

In Germany it is mandatory for all new houses (and older ones which get rewired ) to fit a so-called F1 trip switch ( Residual Current Circuit Breaker ) for all circuits in wet rooms.
 
russ_watters said:
Note that some may have GFCI and not realize it. My house has an odd "house GFCI" circuit, which appears to be based on one GFCI receptacle in the garage wired in series with the rest of the "wet" receptacles (3 bathrooms, 2 outside).
This is very common. I don't like it but many contractors get by with it.
 
Guineafowl said:
...
Mention using an electric heater on a cord into a bathroom and most here would give a little intake of breath (you know, the 'experts' propping up the bar). You may have rigged it fairly safely but there's always that little mental flag. If it's OK to use mains in the bathroom then why do you never see a socket in there?
...
I've had an oil filled portable heater in my bathroom for 28 years*. Never had a problem.
Of course, it's plugged into my GFCI outlet, which is directly above it.
I also have a handheld hair dryer hanging above the heater, which I think I've used about 5 times in those 28 years. [It may have been from a "long-hair" phase during my youth]

*My house is heated with baseboard heaters, and there wasn't one in the bathroom, so it was always the coldest room in the house, which didn't really make sense, since it was the only room where I had to get wet whilst totally naked, which was NOT very comfortable, to say the least. Beings that it was centrally located in my house, with rooms all around, the electric oil heater could be used to heat the room during the night to a comfortable 75°F, while the rest of the house stayed at a semi-comfortable 65°F. After my shower in the morning, I would turn off the heater, leave the door open, and let the moisture dissipate throughout the house. At night, before I went to bed, I would turn on the heater, and shut the door. Repeat, for 25 years, Monday through Friday.

Obligatory picture, as, it all makes sense, if you look at it:

2017.07.18.Oms.home.ventilation.layout.png
 
@ russ_watters,

just noticed something really funny in your last post which I have highlighted in bold print!

"russ_watters said: ↑
Note that some may have GFCI and not realize it. My house has an odd "house GFCI" circuit, which appears to be based on one GFCI receptacle in the garage wired in series with the rest of the "wet" receptacles (3 bathrooms, 2 outside)".

Why do you have 2 of your bathrooms outside?
 
@ OmCheeto,
guess you do not shower on weekends as you stated in your post

"Repeat, for 25 years, Monday through Friday".
 
OmCheeto said:
Never had a problem

I'm sure that's true. But there's really no accounting for idiocy, and although you, a member of PF and therefore presumably someone relatively 'switched on' about electrical safety, have not had a problem, it doesn't necessarily mean there's no problem to be had.

It's almost the same fallacy as on another forum I'm a member of, for car mechanics discussions - "I've worked under the car with only the jack for support for 30 years, never had a problem".
 
The Wizard said:
@ OmCheeto,
guess you do not shower on weekends as you stated in your post

"Repeat, for 25 years, Monday through Friday".
Correct!
But, I retired 3 years ago, and bathe now about once every two weeks. It's somewhat stinky. I would not recommend it for people with active social lives. My friends have recently learned to contact me 24 hours in advance, of "close quarters" mutual activities. ie. Sitting on a beach, where I might be upwind of them.
 
anorlunda said:
Today's news contains photos of the frayed extension cord that electrocuted the girl.
Link? My Google-foo is failing me at the moment...
 
Guineafowl said:
I'm sure that's true. But there's really no accounting for idiocy, and although you, a member of PF and therefore presumably someone relatively 'switched on' about electrical safety, have not had a problem, it doesn't necessarily mean there's no problem to be had.

It's almost the same fallacy as on another forum I'm a member of, for car mechanics discussions - "I've worked under the car with only the jack for support for 30 years, never had a problem".
Well, as Jim Hardy mentioned earlier about his refrigerator developing a ground fault, I'm pretty sure that old electric oil heater will be recycled the first time it trips the circuit.

ps. I've never worked under a car with only "ONE" :bugeye: jack for support. As I mentioned, I'm a former nuclear power plant technician, and know of "Black Swan" events.
hmmm... Perhaps I should add that to my signature; "Expect the unexpected."

[(off topic)1000]
pps. Did I ever tell anyone about the time I averted a reactor meltdown?
I think I was 22 years old.
Weird to think about that now.
[/(off topic)1000]
 
The Wizard said:
@ russ_watters,

just noticed something really funny in your last post which I have highlighted in bold print!

"russ_watters said: ↑
Note that some may have GFCI and not realize it. My house has an odd "house GFCI" circuit, which appears to be based on one GFCI receptacle in the garage wired in series with the rest of the "wet" receptacles (3 bathrooms, 2 outside)".

Why do you have 2 of your bathrooms outside?
Not sure if serious, but it can be read two different ways.

That said, last year I took a buck-naked shower outside a hut on the African plains. It was glorious.
 
The Wizard said:
Just to confirm some points regarding UK & european bathroom fittings. In the UK there are no wall mounted switches allowed, the only switch approved for bathrooms is a ceiling mounted switch operated by a cord hanging down from it to operate the light.

That's no longer correct. You can put a wall switch in a bathroom as long as it's in the right "zone" (outside zone 2 I think) and you follow the manufacturers instructions (which may preclude use in a humid area). In practice that latter requirement will prevent you using most regular wall switches but it's not a regulation thing anymore. See also..

http://www.theiet.org/forums/forum/messageview.cfm?catid=205&threadid=53790

There are some proximity switches that are designed to be hidden behind ceramic tiles or mirrors etc
 
russ_watters said:
Not sure if serious, but it can be read two different ways.
I'm surprised that you can supply 3 baths and 2 outside sockets from one circuit.
I was worried about my single bathroom being overloaded.

That said, last year I took a buck-naked shower outside a hut on the African plains. It was glorious.
Ok, that's like off topic, to the infinity power...
 
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Most of the resistance that saves you from electrocution from occasional contact with 110 or 240 V comes from dry skin. If the skin is wet the voltage required to get a lethal current is a lot lower. People have killed themselves by inserting 9V batteries into body openings. It might be that 5V is enough with a wet hand when the rest of the body is probably grounded via wet skin, water and the grounded / Earthed pipework to the bath.
 
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CWatters said:
it makes more sense for the washing machine to go in the bathroom on the middle floor rather than in the kitchen on the ground floor.
i always wondered why aren't the washer and dryer in or adjacent the bedroom, where the laundry is generated ? That's where i change clothes & bedding, and towels are in the bathroom which is always near bedrooms. I plan to relocate my laundry close to bedroom and bath. Sigh, so many projects so little time !

dlgoff said:
Yep. I have one in the bathroom that's also wired to an outside receptacle.
That mighta made sense long ago when they were expensive. Nowadays they're under ten bucks and it's false economy.
Capacitance of long wires daisy-chaining them like that can give false trips especially when it's wet (dielectric constant of water is ~80) .
I have one GFCI in a panel that a certain electronic fluorescent ballast will trip just often enough to be a nuisance . It feeds the bathroom and the garage.
I prefer to use individual GFCI receptacles everywhere they're needed so will be replacing that breaker with a plain one. That way , for example, something in the bathroom won't kill power to the garage and defrost a freezer out there. Good explanation of how they work here...
http://www.shelfkey.com/DataSheets/937747.pdf

upload_2017-7-18_12-26-15.png


Early GFCI's were perturbed by lightning. It would trip them or fry the electronics inside . I notice new ones are way better in that regard.
Probably that MOV in upper left is a "School of Hard Knocks" late addition. I don't remember seeing it in the 1975 - ish datasheet.old jim
 
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JohnM said:
...
People have killed themselves by inserting 9V batteries into body openings.
...
Is it just me, or are kids nowadays, kind of, weird?
 
OmCheeto said:
pps. Did I ever tell anyone about the time I averted a reactor meltdown?
Would you have to shoot us if you did?