USB Charger electrocution

[RMD]

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail, in both the
USB-Charger and in the laptop headphones and laptop charger, to
produce the electrocution, which seems rather improbable to me.

I'm not doubting the fact of the electrocution, just the alleged
method. No one has mentioned a nearby lightning strike, but that seems
more likely than the proposed mechanism.

Or am I missing something obvious?

Ross

 

[Tony]

On 28/06/2014 1:49 PM, RMD wrote:

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail, in both the
USB-Charger and in the laptop headphones and laptop charger, to
produce the electrocution, which seems rather improbable to me.

I'm not doubting the fact of the electrocution, just the alleged
method. No one has mentioned a nearby lightning strike, but that seems
more likely than the proposed mechanism.

Or am I missing something obvious?

Ross

I agree. I was not aware of a lightning strike though.
When I first heard of it I imagined headphones connected to a grounded
class 1 system and a fault in the class 2 USB charger.

Tony

 

[news13]

On Sat, 28 Jun 2014 05:49:22 +0000, RMD wrote:

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail,

What double insulation?

 

[Phil Allison]

"RMD"

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail, in both the
USB-Charger and in the laptop headphones and laptop charger, to
produce the electrocution, which seems rather improbable to me.

** The only device that has been claimed to be faulty is the USB charger
used with the phone. Most laptops are earthed to the AC safety ground when
charging, which seems the only way the victim could have completed a circuit
to ground if she had hold of some metal part of it.

I'm not doubting the fact of the electrocution, just the alleged
method. No one has mentioned a nearby lightning strike, but that seems
more likely than the proposed mechanism.

** Yep - my first thought was that the alleged burn injuries were more
likely from lightning.


> Or am I missing something obvious?

** Wait for the Coroner's report - cos that will contain actual facts.


.... Phil

 

[Bob Milutinovic]

"Tony" <nomail@nospam.com> wrote in message
news:lolpjp$cu$1@dont-email.me...

On 28/06/2014 1:49 PM, RMD wrote:
Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail, in both the
USB-Charger and in the laptop headphones and laptop charger, to
produce the electrocution, which seems rather improbable to me.

I'm not doubting the fact of the electrocution, just the alleged
method. No one has mentioned a nearby lightning strike, but that seems
more likely than the proposed mechanism.

Or am I missing something obvious?

Ross


I agree. I was not aware of a lightning strike though.
When I first heard of it I imagined headphones connected to a grounded
class 1 system and a fault in the class 2 USB charger.

You left the class 3 police and class 4 journalists out of the equation -
there's a lot of stupidity in this world, and it seems to be concentrated
among those who're supposedly credible :-(

I know of precisely zero laptops which can be charged from a USB charger -
they all need in excess of 15V (even "netbooks" need at least 12V) at
several amps, whereas even the most powerful USB chargers can barely muster
2A and never above 5V.

If the "USB charger" was in fact a device which plugged into her laptop's
USB port and provided power to yet another device, how the f*** did she
manage to get electrocuted by 5VDC?

Based on what I've seen on assorted web sites, I'm more inclined to think
that she was having a bath with her laptop by her side, likely on webcam
with someone, when the laptop and charger both fell into the tub.

--
Bob Milutinovic
Cognicom

 

[Sylvia Else]

On 28/06/2014 3:49 PM, RMD wrote:

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail, in both the
USB-Charger and in the laptop headphones and laptop charger, to
produce the electrocution, which seems rather improbable to me.

In a properly designed and constructed charger, that's true.

Some of the USB chargers that can be bought from China are not properly
designed, and electrocution is not especially unlikely.

Sylvia.

 

[news13]

On Sun, 29 Jun 2014 14:14:34 +1000, Phil Allison wrote:

"news13"
RMD wrote:

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail,

What double insulation?


** You being funny or you have no idea what "double insulation" means ?

My understanding was that they didn't meet Aussie standard and thus were
not double insulated.

 

[Phil Allison]

"news13"

Phil Allison wrote:
"news13"

What double insulation?


** You being funny or you have no idea what "double insulation" means ?

My understanding was that they didn't meet Aussie standard and thus were
not double insulated.

** So Australia has the only "double insulated" electrical appliances in the
world ?

FYI:

Australian electrical standards are closely derived from similar IEC
standards.

Almost every country in the world is a member (or affiliate) of the IEC -
including China.

http://en.wikipedia.org/wiki/International_Electrotechnical_Commission

If a manufacturer builds an item to meet double insulation requirements,
they can use the double square symbol - no outside certification is
required for that.

However, items like USB chargers fall into special category (called
prescribed items) where agency certification and labelling to the relevant
Australian standard is legally essential in order to go on sale here.

For items made in China, such certification can be done by locally and is
normally little more than a formality - assuming that the design meets
international standards.



..... Phil

 

[Phil Allison]

"news13"

RMD wrote:

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail,

What double insulation?

** You being funny or you have no idea what "double insulation" means ?



.... Phil

 

[Sylvia Else]

On 29/06/2014 2:39 PM, news13 wrote:

On Sun, 29 Jun 2014 14:14:34 +1000, Phil Allison wrote:

"news13"
RMD wrote:

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail,

What double insulation?


** You being funny or you have no idea what "double insulation" means ?

My understanding was that they didn't meet Aussie standard and thus were
not double insulated.

Double insulated means just what it says. The low voltage side must be
separated from the high voltage side by two insulators, each of which
is, on its own, capable of resisting the mains voltage.

Sylvia.

 

[Phil Allison]

"Sylvia Else"

Phil Allison wrote:


** You being funny or you have no idea what "double insulation" means ?

My understanding was that they didn't meet Aussie standard and thus were
not double insulated.


Double insulated means just what it says.

** Fraid that is not the case in reality.

The low voltage side must be separated from the high voltage side by two
insulators, each of which is, on its own, capable of resisting the mains
voltage.

** However the rules for class II appliances are not so pedantic.

A single layer of a specified material and thickness may be sufficient as
long as it is not subject to deterioration in use, or a gap on a PCB between
live conductors and user accessible metal few mm wide, or the live and
accessible metal parts are bridged only by a class Y capacitor of approved
design and low enough value.

Double Insulation sounded like a brilliant idea once - but has been
gradually whittled down and compromised in so many ways that it is now real
worry considering you have to trust notoriously dodgy Chinese manufacturing
culture to get it right all the time, or you could die.



..... Phil

 

[asdf]

RMD wrote:

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail, in both the
USB-Charger and in the laptop headphones and laptop charger, to
produce the electrocution, which seems rather improbable to me.

I'm not doubting the fact of the electrocution, just the alleged
method. No one has mentioned a nearby lightning strike, but that seems
more likely than the proposed mechanism.

Or am I missing something obvious?

Ross

Sounds very similar to this one year old news.

http://tinyurl.com/qzmmglj

 

[Tony]

On 1/07/2014 4:39 AM, asdf wrote:

RMD wrote:

Hi All,

No doubt you have all read or heard about this recent story;

http://tinyurl.com/llkx7dw

It seems to me a lot of double-insulation has to fail, in both the
USB-Charger and in the laptop headphones and laptop charger, to
produce the electrocution, which seems rather improbable to me.

I'm not doubting the fact of the electrocution, just the alleged
method. No one has mentioned a nearby lightning strike, but that seems
more likely than the proposed mechanism.

Or am I missing something obvious?

Ross

Sounds very similar to this one year old news.

http://tinyurl.com/qzmmglj

It makes me wonder how many electric shocks, burned out chargers and
fires have actually happened and never been reported. It's only the
extreme cases that make the headlines. If you get shocked by a device
you are using every day, wouldn't you report it to consumer protection
(1300 30 40 54) ?

Funny how this thread got killed and another one opened.

Tony

 

[Clocky]

On 29/06/2014 4:38 PM, Phil Allison wrote:

"Sylvia Else"
Phil Allison wrote:


** You being funny or you have no idea what "double insulation" means ?

My understanding was that they didn't meet Aussie standard and thus were
not double insulated.


Double insulated means just what it says.

** Fraid that is not the case in reality.

The low voltage side must be separated from the high voltage side by two
insulators, each of which is, on its own, capable of resisting the mains
voltage.

** However the rules for class II appliances are not so pedantic.

A single layer of a specified material and thickness may be sufficient as
long as it is not subject to deterioration in use, or a gap on a PCB between
live conductors and user accessible metal few mm wide, or the live and
accessible metal parts are bridged only by a class Y capacitor of approved
design and low enough value.

Double Insulation sounded like a brilliant idea once - but has been
gradually whittled down and compromised in so many ways that it is now real
worry considering you have to trust notoriously dodgy Chinese manufacturing
culture to get it right all the time, or you could die.

A youtube video exists that determines that the high voltage side of one
of these cheap Chinese chargers is isolated from the low voltage side by
a thickness of .25mm between two soldered joints.

That is clearly not just a case of dodgey manufacturing, but really bad
engineering in the first place.

I've got one of those $1 chargers mentioned before headed my way, not
for use obviously, but for inspection.

 

[F Murtz]

Clocky wrote:

On 29/06/2014 4:38 PM, Phil Allison wrote:
"Sylvia Else"
Phil Allison wrote:


** You being funny or you have no idea what "double insulation"
means ?

My understanding was that they didn't meet Aussie standard and thus
were
not double insulated.


Double insulated means just what it says.

** Fraid that is not the case in reality.

The low voltage side must be separated from the high voltage side by two
insulators, each of which is, on its own, capable of resisting the mains
voltage.

** However the rules for class II appliances are not so pedantic.

A single layer of a specified material and thickness may be sufficient as
long as it is not subject to deterioration in use, or a gap on a PCB
between
live conductors and user accessible metal few mm wide, or the live and
accessible metal parts are bridged only by a class Y capacitor of
approved
design and low enough value.

Double Insulation sounded like a brilliant idea once - but has been
gradually whittled down and compromised in so many ways that it is now
real
worry considering you have to trust notoriously dodgy Chinese
manufacturing
culture to get it right all the time, or you could die.



A youtube video exists that determines that the high voltage side of one
of these cheap Chinese chargers is isolated from the low voltage side by
a thickness of .25mm between two soldered joints.

That is clearly not just a case of dodgey manufacturing, but really bad
engineering in the first place.

I've got one of those $1 chargers mentioned before headed my way, not
for use obviously, but for inspection.

Got two of those, one physically blew the usb plug clean out of the
socket when I was not looking.
[img:d1397d9237]http://i60.tinypic.com/14mb4m9.jpg[/img:d1397d9237]

 

[Clocky]

On 9/07/2014 6:31 AM, F Murtz wrote:

Clocky wrote:
On 29/06/2014 4:38 PM, Phil Allison wrote:
"Sylvia Else"
Phil Allison wrote:


** You being funny or you have no idea what "double insulation"
means ?

My understanding was that they didn't meet Aussie standard and thus
were
not double insulated.


Double insulated means just what it says.

** Fraid that is not the case in reality.

The low voltage side must be separated from the high voltage side by
two
insulators, each of which is, on its own, capable of resisting the
mains
voltage.

** However the rules for class II appliances are not so pedantic.

A single layer of a specified material and thickness may be
sufficient as
long as it is not subject to deterioration in use, or a gap on a PCB
between
live conductors and user accessible metal few mm wide, or the live and
accessible metal parts are bridged only by a class Y capacitor of
approved
design and low enough value.

Double Insulation sounded like a brilliant idea once - but has been
gradually whittled down and compromised in so many ways that it is now
real
worry considering you have to trust notoriously dodgy Chinese
manufacturing
culture to get it right all the time, or you could die.



A youtube video exists that determines that the high voltage side of one
of these cheap Chinese chargers is isolated from the low voltage side by
a thickness of .25mm between two soldered joints.

That is clearly not just a case of dodgey manufacturing, but really bad
engineering in the first place.

I've got one of those $1 chargers mentioned before headed my way, not
for use obviously, but for inspection.




Got two of those, one physically blew the usb plug clean out of the
socket when I was not looking.
[img:027daaba18]http://i60.tinypic.com/14mb4m9.jpg[/img:027daaba18]

That's nasty and you're lucky you weren't hanging onto it, or the phone.
Don't use the other one, rip it apart and see how close the mains input
is to the output.

Unfortunately it's not only chargers that end up burning. I bought one
of those little wireless keyboards that come with a USB dongle.

I used it for months without issue, then one day I was using it and the
keyboard suddenly stopped working. I thought the keyboard needed
charging, but then I noticed a burning plastic smell.

It was the dongle, it was so hot that it had turned it's housing into a
Dali.

Lucky there was no permanent damage to the PC.

 

[Phil Allison]

"Clocky"

Phil Allison wrote:
"Sylvia Else"
Phil Allison wrote:


** However the rules for class II appliances are not so pedantic.

A single layer of a specified material and thickness may be sufficient as
long as it is not subject to deterioration in use, or a gap on a PCB
between
live conductors and user accessible metal few mm wide, or the live and
accessible metal parts are bridged only by a class Y capacitor of
approved
design and low enough value.

Double Insulation sounded like a brilliant idea once - but has been
gradually whittled down and compromised in so many ways that it is now
real
worry considering you have to trust notoriously dodgy Chinese
manufacturing
culture to get it right all the time, or you could die.



A youtube video exists that determines that the high voltage side of one
of these cheap Chinese chargers is isolated from the low voltage side by a
thickness of .25mm between two soldered joints.

** If that is the video by Dave Jones, then it is irrelevant to my point.

That is clearly not just a case of dodgey manufacturing, but really bad
engineering in the first place.

** It is clearly a case of criminal fraud by the Chinese makers and the HK
based dealers on ebay etc.

Got nothing to do with the millions of supplies that come with new equipment
and are sold by regular importers.

I've got one of those $1 chargers mentioned before headed my way, not for
use obviously, but for inspection.

** Cheap thrills - eh ?


..... Phil

 

[Clocky]

On 9/07/2014 9:24 AM, Phil Allison wrote:

"Clocky"
Phil Allison wrote:
"Sylvia Else"
Phil Allison wrote:


** However the rules for class II appliances are not so pedantic.

A single layer of a specified material and thickness may be sufficient as
long as it is not subject to deterioration in use, or a gap on a PCB
between
live conductors and user accessible metal few mm wide, or the live and
accessible metal parts are bridged only by a class Y capacitor of
approved
design and low enough value.

Double Insulation sounded like a brilliant idea once - but has been
gradually whittled down and compromised in so many ways that it is now
real
worry considering you have to trust notoriously dodgy Chinese
manufacturing
culture to get it right all the time, or you could die.



A youtube video exists that determines that the high voltage side of one
of these cheap Chinese chargers is isolated from the low voltage side by a
thickness of .25mm between two soldered joints.

** If that is the video by Dave Jones, then it is irrelevant to my point.

It's not the video by Dave Jones which I have also seen. He too noticed
the poor isolation between mains and output IIRC so it's relevant to my
point.

That is clearly not just a case of dodgey manufacturing, but really bad
engineering in the first place.

** It is clearly a case of criminal fraud by the Chinese makers and the HK
based dealers on ebay etc.

I don't think they deliberately set out to kill people, but clearly poor
design and manufacture is having that effect.

Got nothing to do with the millions of supplies that come with new equipment
and are sold by regular importers.

Nobody said it did.

I've got one of those $1 chargers mentioned before headed my way, not for
use obviously, but for inspection.

** Cheap thrills - eh ?

Not as cheap as one of your rants ;-)

 

[Phil Allison]

"Clocky"

Phil Allison wrote:
"Clocky"
Phil Allison wrote:
"Sylvia Else"
Phil Allison wrote:


** However the rules for class II appliances are not so pedantic.

A single layer of a specified material and thickness may be sufficient
as
long as it is not subject to deterioration in use, or a gap on a PCB
between live conductors and user accessible metal few mm wide, or the
live and
accessible metal parts are bridged only by a class Y capacitor of
approved design and low enough value.

Double Insulation sounded like a brilliant idea once - but has been
gradually whittled down and compromised in so many ways that it is now
real worry considering you have to trust notoriously dodgy Chinese
manufacturing culture to get it right all the time, or you could die.



A youtube video exists that determines that the high voltage side of one
of these cheap Chinese chargers is isolated from the low voltage side by
a
thickness of .25mm between two soldered joints.

** If that is the video by Dave Jones, then it is irrelevant to my point.

It's not the video by Dave Jones which I have also seen. He too noticed
the poor isolation between mains and output IIRC so it's relevant to my
point.

** Shame your point has nothing to do with the para you posted under.

That is clearly not just a case of dodgey manufacturing, but really bad
engineering in the first place.

** It is clearly a case of criminal fraud by the Chinese makers and the
HK
based dealers on ebay etc.


I don't think they deliberately set out to kill people,

** Nobody said they did - fraud is not connected to murder.

So another total irrelevance.

Got nothing to do with the millions of supplies that come with new
equipment
and are sold by regular importers.


Nobody said it did.

** By posting your drivel where you did, you made that implication.

With any luck, your $1 Chink time bomb will kill you.


..... Phil

 

[Clocky]

On 9/07/2014 2:53 PM, Phil Allison wrote:

"Clocky"
Phil Allison wrote:
"Clocky"
Phil Allison wrote:
"Sylvia Else"
Phil Allison wrote:


** However the rules for class II appliances are not so pedantic.

A single layer of a specified material and thickness may be sufficient
as
long as it is not subject to deterioration in use, or a gap on a PCB
between live conductors and user accessible metal few mm wide, or the
live and
accessible metal parts are bridged only by a class Y capacitor of
approved design and low enough value.

Double Insulation sounded like a brilliant idea once - but has been
gradually whittled down and compromised in so many ways that it is now
real worry considering you have to trust notoriously dodgy Chinese
manufacturing culture to get it right all the time, or you could die.



A youtube video exists that determines that the high voltage side of one
of these cheap Chinese chargers is isolated from the low voltage side by
a
thickness of .25mm between two soldered joints.

** If that is the video by Dave Jones, then it is irrelevant to my point.

It's not the video by Dave Jones which I have also seen. He too noticed
the poor isolation between mains and output IIRC so it's relevant to my
point.

** Shame your point has nothing to do with the para you posted under.


That is clearly not just a case of dodgey manufacturing, but really bad
engineering in the first place.

** It is clearly a case of criminal fraud by the Chinese makers and the
HK
based dealers on ebay etc.


I don't think they deliberately set out to kill people,

** Nobody said they did -

I said they didn't, nobody said they did.

fraud is not connected to murder.
>

I didn't say it was, and it wouldn't be murder in any case.

So another total irrelevance.

Much like most of your posts.

Got nothing to do with the millions of supplies that come with new
equipment
and are sold by regular importers.


Nobody said it did.

** By posting your drivel where you did, you made that implication.

I certainly did not, you just made your usual assumptions based in your
incomprehension.

With any luck, your $1 Chink time bomb will kill you.

Unlike you Phil, I know what I'm doing.