On Mar 13, 7:35*pm, ":Jerry:" wrote:
"stevelup" wrote in message

...
snip

http://improve-usenet.org/index.html

You really are a complete plank aren't you?

When you have learned to quote properly, *and* stop using Outlook
Express as your newsreader, please feel free to come back and
criticise others.

In the meantime, go and investigate how to electrocute an elephant
with 1V.

On Mar 13, 7:38*pm, Owain wrote:
stevelup wrote:
What you have neglected to take into consideration is that with such
low voltages, there can only be incredibly low currents passing
through the relatively high resistance of an extremely large elephant.

What about a small elephant?

Is there a difference between African and Indian elephants?

In the absence of elephants with which to carry out a practical
experiment, could I kidnap some members of the local international
students' society, electrocute them, and extrapolate the results to
elephants?

Owain

I think you would more informative results by attempting to
electrocute :Jerry: using a watch battery.

On Mar 13, 8:26*pm, "Man at B&Q" wrote:
On Mar 13, 7:38*pm, Owain wrote:

stevelup wrote:
What you have neglected to take into consideration is that with such
low voltages, there can only be incredibly low currents passing
through the relatively high resistance of an extremely large elephant.

What about a small elephant?

Is there a difference between African and Indian elephants?

What about the fifth elephant?

MBQ

Groan.

On Mar 13, 7:40*pm, Andy Burns wrote:
On 13/03/2008 14:13, Man at B&Q wrote:

Explain how you will get a hazardous current to flow through a human
with a potential of 5v AC

I've seen figures for arm-to-arm resistance as between 500 and 1000 ohms
with good contact, and 16mA as the lowest "can't let go" current for AC,
so with a better source of 5V than in the original scenario, it's only
about a factor of two out.

Ok. But you have missed the more important part of this discussion.

What about 1V through an elephant?

On 2008-03-13 19:31:46 +0000, ":Jerry:" said:


"stevelup" wrote in message
...
On Mar 13, 5:47 pm, ":Jerry:" wrote:
"Bob Mannix" wrote in message

snip
He's not FFS (again). Yes many amps will kill, we know that but
sod
all volts = sod all amps, NOT MANY, unless you are a metal bar.
Jeez! 5v isn't going to affect anyone, wet or not.

WWHHHOOOSSSSHHH........

Hey - at least that bit was quoted properly...

Yes because he is using a proper nntp server unlike you.

Here you go. I posted this from my Giganews account instead.

Does that make you feel better...

you cannot be serious!

http://www.bbc.co.uk/radio/aod/netwo...io4/nigh****ch

how to electrocute the turtle
on which discworld flies?

Terry Pratchett's Night Watch - Commander Sam Vimes falls through a hole in
time...

"Andy Burns" wrote in message
...
On 13/03/2008 14:13, Man at B&Q wrote:

Explain how you will get a hazardous current to flow through a human
with a potential of 5v AC

I've seen figures for arm-to-arm resistance as between 500 and 1000 ohms
with good contact, and 16mA as the lowest "can't let go" current for AC,

Where? "I've seen figures" is an all to coomon and excessively pointless and
irritating point to often made on ng's! "I've seen figures (reference
quote)" on the other hand is just the opposite.


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

"George (dicegeorge)" wrote in message
...

When i was a boy i'd lick the end of a 9volt battery with my tongue and
get a tingle!

I started a fire once running 12volts DC through a too thin wire,
the plastic round the wire melted and burnt poisonously,
it could probably be done with a 6 volt motorbike battery..

But i doubt if you could light a bicycle light bulb with the 5volt AC
which the original poster measured on his mains when turned off...

A friend when I was young put the two wires from the poorly regulated 12V
train track transformer on his tongue. Granted he (nor I, having seen it)
would ever do it again but he suffered no permanent damage!

As another poster said, 50V is (give or take) where it starts getting dodgy.
The same friend (as it happens, must be something about him!) did get stuck
on a 110V DC supply, through his hands and down to his feet which were bare,
on steel boat deck plates. Now we are actually in the realms of "it's the
mills that kills" rather than in the fantasy world of the 5V'ers. Yes he was
on the way out, he couldn't let go and knew he was blacking out and a goner.
One of the crew found him and threw the breaker in time (fortunately).

Know your enemy. A 110V DC supply on a boat is effing dangerous. 5V anywhere
isn't to humans as electricity.

I deal with large power supplies in my work - a 50V, 10000A power supply
(which we have) isn't particularly dangerous (unless you drop something
metal across the output and get flash burns). You could put your hand on the
conductors (unless stood in a metal bucket of water) and it's immaterial
whether it's a 10000A supply or a 1A supply, you would get a bit of a
tingle. Another supply up the way is about 130V /500A. This is a dangerous
beast to work on as the voltage is too high.


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

On Mar 13, 7:35*pm, ":Jerry:" wrote:
"stevelup" wrote in message

...
snip

http://improve-usenet.org/index.html

Does it not strike you as strange, :Jerry:, that you are in a minority
of one in having trouble correctly quoting posts in thread?

MBQ

On 14/03/2008 07:28, Bob Mannix wrote:

"Andy Burns" wrote:

I've seen figures for arm-to-arm resistance as between 500 and 1000 ohms
with good contact, and 16mA as the lowest "can't let go" current for AC,

Where?

e.g.

http://www.phys.washington.edu/users...433safety.html

"stevelup" wrote in message
...
On Mar 13, 7:31 pm, ":Jerry:" wrote:
"stevelup" wrote in message

...
On Mar 13, 5:47 pm, ":Jerry:" wrote:

"Bob Mannix" wrote in message

snip
He's not FFS (again). Yes many amps will kill, we know that but
sod
all volts = sod all amps, NOT MANY, unless you are a metal bar.
Jeez! 5v isn't going to affect anyone, wet or not.

WWHHHOOOSSSSHHH........

Hey - at least that bit was quoted properly...

Yes because he is using a proper nntp server unlike you.

Who's he? I replied to you!

Read the attributions, assuming you know how...

In uk.d-i-y, stevelup wrote:
On Mar 13, 7:40*pm, Andy Burns wrote:
On 13/03/2008 14:13, Man at B&Q wrote:

Explain how you will get a hazardous current to flow through a human
with a potential of 5v AC

I've seen figures for arm-to-arm resistance as between 500 and 1000 ohms
with good contact, and 16mA as the lowest "can't let go" current for AC,
so with a better source of 5V than in the original scenario, it's only
about a factor of two out.

Ok. But you have missed the more important part of this discussion.

What about 1V through an elephant?

You can't put volts *through* anything. You put volts across something
and *amps* go through that something. Which is where we came in, I think.

--
Mike Barnes

"Andy Burns" wrote in message
...
On 14/03/2008 07:28, Bob Mannix wrote:

"Andy Burns" wrote:

I've seen figures for arm-to-arm resistance as between 500 and 1000 ohms
with good contact, and 16mA as the lowest "can't let go" current for AC,

Where?

e.g.

http://www.phys.washington.edu/users...433safety.html

Which says lowest resistance 1000 Ohms, not 500-1000Ohms and says 100mA
possible heart stoppage - ie 110V mains can kill. Did anyone say it
couldn't? Au contraire, we have all agreed that point (including me).

5V, with the lowest possible contact resistance (ie two wet hands grasping
metal rods) you are down at "definite shock" levels (ie you feel it). You
only have access to one connection anyway in the situation under description
and the resistances then skyrocket up into the 10's of kOhm and you will
feel nothing.


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

On 14/03/2008 09:29, Bob Mannix wrote:
"Andy Burns"

Which says lowest resistance 1000 Ohms, not 500-1000Ohms

http://www.ese.upenn.edu/rca/geninfo/safety.html

So if dripping wet through, gripping two large electodes very tightly,
tensing all your muscles 12V AC *might* be enough to "lock you on".

I don't think anyone said that the original 5V was dangerous.

On 14 Mar, 07:39, "Bob Mannix" wrote:
"George (dicegeorge)" wrote in message
...

When i was a boy i'd lick the end of a 9volt battery with my tongue and
get a tingle!

I started a fire once running 12volts DC through a too thin wire,
the plastic round the wire melted and burnt poisonously,
it could probably be done with a 6 volt motorbike battery..

But i doubt if you could light a bicycle light bulb with the 5volt AC
which the original poster measured on his mains when turned off...

A friend when I was young put the two wires from the poorly regulated 12V
train track transformer on his tongue. Granted he (nor I, having seen it)
would ever do it again but he suffered no permanent damage!

As another poster said, 50V is (give or take) where it starts getting dodgy.
The same friend (as it happens, must be something about him!) did get stuck
on a 110V DC supply, through his hands and down to his feet which were bare,
on steel boat deck plates. Now we are actually in the realms of "it's the
mills that kills" rather than in the fantasy world of the 5V'ers. Yes he was
on the way out, he couldn't let go and knew he was blacking out and a goner.
One of the crew found him and threw the breaker in time (fortunately).

Know your enemy. A 110V DC supply on a boat is effing dangerous. 5V anywhere
isn't to humans as electricity.

I deal with large power supplies in my work - a 50V, 10000A power supply
(which we have) isn't particularly dangerous (unless you drop something
metal across the output and get flash burns). You could put your hand on the
conductors (unless stood in a metal bucket of water) and it's immaterial
whether it's a 10000A supply or a 1A supply, you would get a bit of a
tingle. Another supply up the way is about 130V /500A. This is a dangerous
beast to work on as the voltage is too high.

And that is one of the reasons why (archaic term coming) telephone
exchanges use equipment powered by 48V DC. It is less dangerous than
using higher voltages. Note that I did not say it was safe - as
pointed out by other people, shorting out a 48V DC supply that can
deliver high currents is a bad thing - so dropping conductive metal
tools onto bare bus-bars or terminals of opposite polarity is
seriously bad news.

However, telephony does have surprises up its sleeve - ringing
currents in the UK are nominally 75V AC at 25Hz, which is enough to
give you a nasty jangle. Thankfully, in normal working they are not
continuous, so giving you time to let go between rings if necessary.

For serious shocks, the old telephone magnetos could give a severe
belt. If you are familiar with really old phones that don't have a
keypad or dial, what they had was a small handle to crank that rang a
bell at the exchange. This was achieved by using a small magneto to
generate the power. Some American ones could generate up to 110V AC at
5 amps (at least according to this website: URL:http://
www.oldphoneman.com/FSMagnetos.htm !

Sid

On Mar 14, 9:03*am, ":Jerry:" wrote:
"stevelup" wrote in message

...
On Mar 13, 7:31 pm, ":Jerry:" wrote:



"stevelup" wrote in message

...
On Mar 13, 5:47 pm, ":Jerry:" wrote:

"Bob Mannix" wrote in message

snip
He's not FFS (again). Yes many amps will kill, we know that but
sod
all volts = sod all amps, NOT MANY, unless you are a metal bar.
Jeez! 5v isn't going to affect anyone, wet or not.

WWHHHOOOSSSSHHH........

Hey - at least that bit was quoted properly...

Yes because he is using a proper nntp server unlike you.

Who's he? I replied to you!

Read the attributions, assuming you know how...

I'm losing the will to live.

For the love of god, *YOU* buggered up the quoting again, not me.

HE-
Hey - at least that bit was quoted properly...

Yes because he is using a proper nntp server unlike you.

My comment at the top, yours on the bottom. Why the hell are you doing
this?

AND AGAIN:-
Who's he? I replied to you!

Read the attributions, assuming you know how...

My comment at the top, yours on the bottom. Are you deliberately doing
this? Even Outlook Express doesn't make such an arse of quoting.

On Mar 14, 8:10*am, "Man at B&Q" wrote:
On Mar 13, 7:35*pm, ":Jerry:" wrote:

"stevelup" wrote in message

...
snip

http://improve-usenet.org/index.html

Does it not strike you as strange, :Jerry:, that you are in a minority
of one in having trouble correctly quoting posts in thread?

MBQ

Every single post he has made has been misquoted. I cannot for love
nor money work out why he is doing it. In the first post, he quoted
using a quote/unquote block like you would use on a web forum. In
all subsequent posts, his reply appears at the same quotation level as
the message he is replying to.

I know he is using Outlook Express, but it does not behave like that.
The worse crime OE does is encourage top posting, it certainly is
capable of quoting correctly.

On Mar 14, 10:21*am, Andy Burns wrote:
On 14/03/2008 09:29, Bob Mannix wrote:

"Andy Burns"
Which says lowest resistance 1000 Ohms, not 500-1000Ohms

http://www.ese.upenn.edu/rca/geninfo/safety.html

So if dripping wet through, gripping two large electodes very tightly,
tensing all your muscles 12V AC *might* be enough to "lock you on".

I don't think anyone said that the original 5V was dangerous.

No but :Jerry: said 1V could kill an elephant...

On Mar 14, 9:10*am, Mike Barnes wrote:
In uk.d-i-y, stevelup wrote:
On Mar 13, 7:40*pm, Andy Burns wrote:
On 13/03/2008 14:13, Man at B&Q wrote:

Explain how you will get a hazardous current to flow through a human
with a potential of 5v AC

I've seen figures for arm-to-arm resistance as between 500 and 1000 ohms
with good contact, and 16mA as the lowest "can't let go" current for AC,
so with a better source of 5V than in the original scenario, it's only
about a factor of two out.

Ok. But you have missed the more important part of this discussion.

What about 1V through an elephant?

You can't put volts *through* anything. You put volts across something
and *amps* go through that something. Which is where we came in, I think.

--
Mike Barnes

I think that is a little pedantic... and I'm sure you were quite aware
that it was a joke, not a scientific statement!

"Andy Burns" wrote in message
...
On 14/03/2008 09:29, Bob Mannix wrote:
"Andy Burns"

Which says lowest resistance 1000 Ohms, not 500-1000Ohms

http://www.ese.upenn.edu/rca/geninfo/safety.html

So if dripping wet through, gripping two large electodes very tightly,
tensing all your muscles 12V AC *might* be enough to "lock you on".

I don't think anyone said that the original 5V was dangerous.

:Jerry: said:


So why are you arguing against yourself then FFS! The point is, it might
not be an elephant, it might be a child having just climbed out of the
bath - sod all amps but many amps will kill - stop suggesting otherwise.

The implication being that such a child was at significant risk from 5V.
Which (s)he isn't. Which is why we all came in.


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

In uk.d-i-y, stevelup wrote:
On Mar 14, 9:10*am, Mike Barnes wrote:
In uk.d-i-y, stevelup wrote:
On Mar 13, 7:40*pm, Andy Burns wrote:
On 13/03/2008 14:13, Man at B&Q wrote:

Explain how you will get a hazardous current to flow through a human
with a potential of 5v AC

I've seen figures for arm-to-arm resistance as between 500 and 1000 ohms
with good contact, and 16mA as the lowest "can't let go" current for AC,
so with a better source of 5V than in the original scenario, it's only
about a factor of two out.

Ok. But you have missed the more important part of this discussion.

What about 1V through an elephant?

You can't put volts *through* anything. You put volts across something
and *amps* go through that something. Which is where we came in, I think.

--
Mike Barnes

I think that is a little pedantic... and I'm sure you were quite aware
that it was a joke, not a scientific statement!

Fair enough, if you understand that it's simply ridiculous to talk of
putting volts through anything, and intended that idea (not just the
elephant) to come across as funny. But it didn't come across that way to
me.

--
Mike Barnes

On Mar 14, 10:21*am, Andy Burns wrote:
On 14/03/2008 09:29, Bob Mannix wrote:

"Andy Burns"
Which says lowest resistance 1000 Ohms, not 500-1000Ohms

http://www.ese.upenn.edu/rca/geninfo/safety.html

So if dripping wet through, gripping two large electodes very tightly,
tensing all your muscles 12V AC *might* be enough to "lock you on".

I don't think anyone said that the original 5V was dangerous.

Maybe not directly, but the argument is about accepting the fact that
it isn't dangerous, and the reasons why it isn't dangerous.

MBQ

On Thu, 13 Mar 2008 17:07:10 GMT, had this to say:

On 13 Mar,
"Man at B&Q" wrote:

Where did I say that amps will not kill? They do, but you need a
sufficiently large voltage to cause the current to flow through a
given load.

I was nearly killed by 50 volts once, but that was because it knocked me of
me perch, but I managed to grab something on the way down.

Much lower wouldn't give a big enough tingle even for that.

I spent nearly 20 years of my working life messing about with 50V dc
(in (G)PO telephone exchanges) and can honestly say that I was unable
to sense its presence 'by hand'.

The real 'shocker' is when it's superimposed with back emfs from
relays etc, and ringing current of some 75V ac; as well as coming into
occasional contact with +/- 80V dc (into inductive loads) on telex
circuits!

As a voltage it's all pretty harmless really - however dropping a
spanner across 10000A+ power busbars produces a somewhat different
effect . Like molten spanners... :-)))

The backup batteries (*large* open-cell lead-acid jobbies) would
barely flinch at such an overload.

--
Frank Erskine

Frank Erskine wrote:
On Thu, 13 Mar 2008 17:07:10 GMT, had this to say:

On 13 Mar,
"Man at B&Q" wrote:

Where did I say that amps will not kill? They do, but you need a
sufficiently large voltage to cause the current to flow through a
given load.
I was nearly killed by 50 volts once, but that was because it knocked me of
me perch, but I managed to grab something on the way down.

Much lower wouldn't give a big enough tingle even for that.

I spent nearly 20 years of my working life messing about with 50V dc
(in (G)PO telephone exchanges) and can honestly say that I was unable
to sense its presence 'by hand'.

The real 'shocker' is when it's superimposed with back emfs from
relays etc, and ringing current of some 75V ac; as well as coming into
occasional contact with +/- 80V dc (into inductive loads) on telex
circuits!

As a voltage it's all pretty harmless really - however dropping a
spanner across 10000A+ power busbars produces a somewhat different
effect . Like molten spanners... :-)))

The backup batteries (*large* open-cell lead-acid jobbies) would
barely flinch at such an overload.

Has anyone mentioned power over ethernet (POE) being at 48 V DC? If it
were not relatively safe a lower voltage would likely have been specified.

--
Rod

Hypothyroidism is a seriously debilitating condition with an insidious
onset.
Although common it frequently goes undiagnosed.
www.thyromind.info www.thyroiduk.org www.altsupportthyroid.org