Electrocution

[John Fortier]

"John Fields" <jfields@austininstruments.com> wrote in message
news:ipvbnvknnsodsgqitn57na89rgnl84l44m@4ax.com...

On 27 Sep 2003 14:04:23 -0700, Captain794@yahoo.com (The Captain) wrote:


Well, trying to ignore the pointless invective and un-needed insults,
one significant difference between a DC voltage and an AC voltage
which measure the same on a voltmeter, is that The DC voltage will be
measured as the actual voltage while the AC voltage will be the RMS
voltage, which is actually .707 of the peak voltage. Therefore, the
peak voltage and current of an AC source will be 1.414 times the
equivalent DC voltage.

---
Yes, I addressed that issue in an earlier post which, apparently, you
missed.
---

And, sorry to disabuse you of your obviously dearly held opinion, the
condition of the victim obviously does have a great deal to do with
the outcome of any shock. Someone with heart desease will be far more
likely to die from an electric shock than someone who is fit and well.
Not all the time and sometines, for reasons I have described
elsewhere in this thread, a fit person will die and an unfit person
live, but that's just chance, and therefore only measured
statistically.

---
Other than just being pig-headed or perhaps not paying attention to what
you've been reading, I really don't understand why you have such a
problem dealing with the fact that regardless of the condition of the
person being "shocked", the current passing through their body as a
result of being connected across the OHMS range of a multimeter will be
the same as the RMS current passing through their body if it were to be
connected to an AC voltage source with the same RMS output voltage as
long as the output impedances of the AC and DC sources were identical.
That was my contention in the beginning, it is now, and unless you can
prove me wrong it will be my contention in the future
---


Also, check my other post, there seems to be, for un-obvious reasons,
a greater chance of surviving a 240/230 volt shock than a 110 volt
shock.

---
Irrelevant to the subject at hand.
---

I realise that you are probably going to scream insults at me for
disagreeing with your opinions, but please try to restrain yourself
and answer, if you wish to, in reaonable terms. To do otherwise is
extremely unprofessional.

---
If you disagree with me and can somehow focus your attention on the
matter being discussed, I welcome your criticism. Otherwise, as far as
I'm concerned you can kiss my unprofessional ass.

--
John Fields

The momentary current of an AC signal will be 1.4.4 times the current of an
equivalent DC current. If that peak co-incides with a point in the heart's
cycle where it is particularly prone to being thrown into fibrillation or
stopped, then there is a greater chance of damage or death occurring.

The average power of the two signals, DC and AC, will be identical.
However, the momentary power will not, and that is what may increase the
danger of AC over DC.

I thought the purpose of this thread was to discuss the properties of
electric shock, which is the subject at hand. If you wish to discuss
another subject, start another thread. I have no intention of kissing any
part of your anatomy. We don't have that kind of relationship.

 

[John Fortier]

"John Fields" <jfields@austininstruments.com> wrote in message
news:ipvbnvknnsodsgqitn57na89rgnl84l44m@4ax.com...

On 27 Sep 2003 14:04:23 -0700, Captain794@yahoo.com (The Captain) wrote:


Well, trying to ignore the pointless invective and un-needed insults,
one significant difference between a DC voltage and an AC voltage
which measure the same on a voltmeter, is that The DC voltage will be
measured as the actual voltage while the AC voltage will be the RMS
voltage, which is actually .707 of the peak voltage. Therefore, the
peak voltage and current of an AC source will be 1.414 times the
equivalent DC voltage.

---
Yes, I addressed that issue in an earlier post which, apparently, you
missed.
---

And, sorry to disabuse you of your obviously dearly held opinion, the
condition of the victim obviously does have a great deal to do with
the outcome of any shock. Someone with heart desease will be far more
likely to die from an electric shock than someone who is fit and well.
Not all the time and sometines, for reasons I have described
elsewhere in this thread, a fit person will die and an unfit person
live, but that's just chance, and therefore only measured
statistically.

---
Other than just being pig-headed or perhaps not paying attention to what
you've been reading, I really don't understand why you have such a
problem dealing with the fact that regardless of the condition of the
person being "shocked", the current passing through their body as a
result of being connected across the OHMS range of a multimeter will be
the same as the RMS current passing through their body if it were to be
connected to an AC voltage source with the same RMS output voltage as
long as the output impedances of the AC and DC sources were identical.
That was my contention in the beginning, it is now, and unless you can
prove me wrong it will be my contention in the future
---


Also, check my other post, there seems to be, for un-obvious reasons,
a greater chance of surviving a 240/230 volt shock than a 110 volt
shock.

---
Irrelevant to the subject at hand.
---

I realise that you are probably going to scream insults at me for
disagreeing with your opinions, but please try to restrain yourself
and answer, if you wish to, in reaonable terms. To do otherwise is
extremely unprofessional.

---
If you disagree with me and can somehow focus your attention on the
matter being discussed, I welcome your criticism. Otherwise, as far as
I'm concerned you can kiss my unprofessional ass.

--
John Fields

Apropos my other answer to you , John, you might want to check out my entry
in the netiquette thread.

 

[John Fields]

On Sun, 28 Sep 2003 15:17:10 GMT, "John Fortier"
<jfortier@rochester.rr.com> wrote:

Apropos my other answer to you , John, you might want to check out my entry
in the netiquette thread.

---
I can't imagine why...

--
John Fields

 

[Fred Abse]

On Sun, 28 Sep 2003 15:32:27 +0100, John Fortier wrote:

The momentary current of an AC signal will be 1.4.4 times the current of
an equivalent DC current.

How do you work that out?

The instantaneous ("momentary") current of an AC signal will be anywhwere
between zero and +/- sqrt(2) of an equivalent direct current, depending
where in the cycle you measure it.

I think you meant "peak current"



--
Then there's duct tape ...
(Garrison Keillor)
nofr@sbhevre.pbzchyvax.pb.hx

 

[John Fields]

On Sun, 28 Sep 2003 14:32:27 GMT, "John Fortier"
<jfortier@rochester.rr.com> wrote:

The momentary current of an AC signal will be 1.4.4 times the current of an
equivalent DC current.
---

Don't you mean 1.414?
---

If that peak co-incides with a point in the heart's
cycle where it is particularly prone to being thrown into fibrillation or
stopped, then there is a greater chance of damage or death occurring.

---
Yes, of course. I believe I mentioned something about this in an
earlier post. Don't you read before you jump in?
---

The average power of the two signals, DC and AC, will be identical.
However, the momentary power will not, and that is what may increase the
danger of AC over DC.

---
I believe power is only indirectly related to causing fibrillation in
that increasing power into the body will cause a larger voltage gradient
to appear across the heart. Certainly, cooking the heart hasn't been
yet considered here.

I thought the purpose of this thread was to discuss the properties of
electric shock, which is the subject at hand. If you wish to discuss
another subject, start another thread.

---
As you become more familiar with Usenet you will find that threads often
change direction, split, abruptly break, and so on, much like a loose
piece of string might. That's why they're called "threads".

The direction I chose to follow in this thread was to disagree with a
poster who claimed that:


"The electrical resistance of the human body is dependent of the
frequency of
the current. At DC, what you measured with the multimeter, skin has very
high resistance. But this resistance decreases quite a bit at 50/60Hz,
therefore increasing the amount of current that can flow through the
victim's body

Albert"

Whether or not I choose to discuss or debate what he wrote on this
thread is my business and I certainly don't need your permission to
proceed in any way I see fit. Moreover, If you're so adamant about
what's on topic and what isn't, I suggest that any comments you choose
to make not directly relating to electrocution be taken to, as you have
suggested, "another thread".

I have no intention of kissing any
part of your anatomy. We don't have that kind of relationship.

---
Nor will we. You seem to have some trouble with recognizing sarcasm, so
I'll merely state that if you need to establish a personal relationship
with someone before engaging in intimate behavior, then go fuck
_yourself_.

--
John Fields

 

[John Fortier]

"John Fields" <jfields@austininstruments.com> wrote in message
news:q19envc8q3jqi4cbbv3njqo1d463inenl2@4ax.com...

On Sun, 28 Sep 2003 15:17:10 GMT, "John Fortier"
jfortier@rochester.rr.com> wrote:


Apropos my other answer to you , John, you might want to check out my
entry
in the netiquette thread.

---
I can't imagine why...

--
John Fields

Well, I can't either, come to think of it. You obviously know everything
already. Must be a nice feeling.

 

[John Fields]

On Sun, 28 Sep 2003 22:44:03 GMT, "John Fortier"
<jfortier@rochester.rr.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:q19envc8q3jqi4cbbv3njqo1d463inenl2@4ax.com...
On Sun, 28 Sep 2003 15:17:10 GMT, "John Fortier"
jfortier@rochester.rr.com> wrote:


Apropos my other answer to you , John, you might want to check out my
entry
in the netiquette thread.

---
I can't imagine why...

--
John Fields


Well, I can't either, come to think of it. You obviously know everything
already. Must be a nice feeling.

---
Actually, I don't know _everything_, although I realize that to you it
must seem like I do.

--
John Fields

 

[The Captain]

John Fields <jfields@austininstruments.com> wrote in message news:<o49envk4lhsam02dds3s7j2tjflesgpgt0@4ax.com>...

On Sun, 28 Sep 2003 14:32:27 GMT, "John Fortier"
jfortier@rochester.rr.com> wrote:


The momentary current of an AC signal will be 1.4.4 times the current of an
equivalent DC current.
---
Don't you mean 1.414?
---

If that peak co-incides with a point in the heart's
cycle where it is particularly prone to being thrown into fibrillation or
stopped, then there is a greater chance of damage or death occurring.

---
Yes, of course. I believe I mentioned something about this in an
earlier post. Don't you read before you jump in?
---

The average power of the two signals, DC and AC, will be identical.
However, the momentary power will not, and that is what may increase the
danger of AC over DC.

---
I believe power is only indirectly related to causing fibrillation in
that increasing power into the body will cause a larger voltage gradient
to appear across the heart. Certainly, cooking the heart hasn't been
yet considered here.

I thought the purpose of this thread was to discuss the properties of
electric shock, which is the subject at hand. If you wish to discuss
another subject, start another thread.

---
As you become more familiar with Usenet you will find that threads often
change direction, split, abruptly break, and so on, much like a loose
piece of string might. That's why they're called "threads".

The direction I chose to follow in this thread was to disagree with a
poster who claimed that:


"The electrical resistance of the human body is dependent of the
frequency of
the current. At DC, what you measured with the multimeter, skin has very
high resistance. But this resistance decreases quite a bit at 50/60Hz,
therefore increasing the amount of current that can flow through the
victim's body

Albert"

Whether or not I choose to discuss or debate what he wrote on this
thread is my business and I certainly don't need your permission to
proceed in any way I see fit. Moreover, If you're so adamant about
what's on topic and what isn't, I suggest that any comments you choose
to make not directly relating to electrocution be taken to, as you have
suggested, "another thread".


I have no intention of kissing any
part of your anatomy. We don't have that kind of relationship.

---
Nor will we. You seem to have some trouble with recognizing sarcasm, so
I'll merely state that if you need to establish a personal relationship
with someone before engaging in intimate behavior, then go fuck
_yourself_.

I certainly have no difficulty in recognising pointlessly fowl
language and childish invective. What precisely do you think you gain
by insulting anyone who disagrees with you? I shall not lower myself
to reply to you at your level, merely urge you to strive to attain
maturity.

Still, "we are all of us human, and some of us much worse." Henry
Fielding.

And the points remain:

Pre-existing physical condition does affect the outcome of an electric
shock,

AC is more dangeraous than DC, due in part to the higher peak voltage,

Co-incidence of this peak with a vulnerable point on the heart's cycle
is more likely to cause damage.

I'd prefer that this discussion, which has descended on John fields'
part to swearing and insult, should cease now. I shall not respond to
any more of fields' posts until he can correspond as a mature
individual, rather than a petulant child.

JF

 

[Don Klipstein]

In art. <5nBdb.169924$834.79975@twister.austin.rr.com>, Vivek Gani wrote:

An architecture student told me once that being shocked by 120 volts AC
is actually worse than 240 volts AC, saying that with 120 volts you
won't easily notice that you're being shocked and thus just remain
holding the wire, whereas with 240 volts, you'll instantly back off.

Sure doesn't sound right to me! Short of conducting little enough
current to be in little danger due to good dry skin, I have always noticed
when I contact 120V.

Also, this summer I accidentally was shocked by 240 volts by touching an
open connection in a breaker box (this was 240 volts in the US). I
just had a weird feeling in my finger for a second then jumped back when
I realized that I was being shocked.
Eh, just thought I'd throw in my two cents...

It is common for contacting 120V to cause shocks that mild (and people
also die from 120V), and 240V can sometimes shock that mildly with dry
skin (but I don't recommend trying). Then again, in the USA most live
conductors for 240V are only 120V from ground.

- Don Klipstein (don@misty.com)

 

[John Fields]

On 28 Sep 2003 19:37:32 -0700, Captain794@yahoo.com (The Captain) wrote:

I certainly have no difficulty in recognising pointlessly fowl
language and childish invective.

---
Yes, I must admit you _do_ have a remarkable grasp of the obvious, but
that's certainly nothing to crow about.
---

What precisely do you think you gain
by insulting anyone who disagrees with you?

---
I don't insult _anyone_ who disagrees with me, but I enjoy jousting with
and unhorsing pompous poppycocks like you.
---

I shall not lower myself
to reply to you at your level, merely urge you to strive to attain
maturity.

---
What you call "maturity" is nothing more than a limitation you would
impose on someone (everyone) to force them to play by your limp-wristed
rules, and I'll have none of it. Limit yourself if you like and then
whine and stamp your feet because you don't want to play in the gutter,
but in the end you'll still be the loser.
---

Still, "we are all of us human, and some of us much worse." Henry
Fielding.

---
"Roses and thorns grow on the same bush." John Fields
---

And the points remain:

Pre-existing physical condition does affect the outcome of an electric
shock,

AC is more dangeraous than DC, due in part to the higher peak voltage,

Co-incidence of this peak with a vulnerable point on the heart's cycle
is more likely to cause damage.

---
You're beating a dead horse as well as being off-topic, since the
discussion in this part of the thread is whether the average current
from an AC source providing an RMS voltage equal to and emanating from
an impedance identical to the DC source will be equal to the DC current.

I will, for your edification, once again post the text of the post
which started this branch of the thread, and which you obviously choose
to ignore:


"The electrical resistance of the human body is dependent of the
frequency of the current. At DC, what you measured with the multimeter,
skin has very high resistance. But this resistance decreases quite a bit
at 50/60Hz, therefore increasing the amount of current that can flow
through the victim's body"


If you read it over many, many times you may come to the realization
that no mention is made of fibrillation, shock, safety, or anything but
the electrical resistance of the human body varying as a function of the
frequency of an electrical signal impressed on the body. If you wish to
discuss that topic then please, feel welcome to do so, but if you wish
to discuss something else then (as you have suggested) take it
elsewhere.
--

I'd prefer that this discussion, which has descended on John fields'
part to swearing and insult, should cease now.

---
More properly, "cursing and insult". However, I suspect that even
bereft of color you would still prefer that this discussion end while
you think you can extricate yourself from the morass into which you've
carelessly fallen.

In any case, it's up to you since silence necessarily follows silence.
---

I shall not respond to
any more of fields' posts until he can correspond as a mature
individual, rather than a petulant child.

---
Blow me :-O

--
John Fields

 

[Albert L.]

I agree.

From a table taken from the "Handbook of Electrical Hazards and Accidents"
published by CRC (1995)

Perception levels in Hand. For DC: 5.2 mA. For 60Hz: 0.4 mA
Painful shock (control not lost) DC: 62 mA. For 60Hz: 9 mA
etc.

Albert

"Don Kelly" <dhky@peeshaw.ca> wrote in message
news:Og7db.26849$I36.12941@pd7tw3no...

"Albert L." <albln@verizon.net> wrote in message
news:bl1n79$1ebe$1@f04n12.cac.psu.edu...
The electrical resistance of the human body is dependent of the
frequency
of
the current. At DC, what you measured with the multimeter, skin has very
high resistance. But this resistance decreases quite a bit at 50/60Hz,
therefore increasing the amount of current that can flow through the
victim's body
----------
Between 60Hz and Dc there is little difference if any and such
differences,
if they exist, are negligible with respect to differences due to other
factors such as skin moisture, salinity, contact area, etc. However there
is a greater sensitivity at 50-60 Hz than at DC or higher frequencies.
--
Don Kelly
dhky@peeshaw.ca
remove the urine to answer

Albert

 

[Pieter Hoeben]

On 25 Sep 2003 20:10:48 -0700, pmolsen@one.net.au (Peter) wrote:

Here in Oz we run 240v which is much nastier than 110v. From what I
read 100mA is very fatal and even 20-30mA can be.

The 20-30 mA is the most dangerous region, as you heart will try to
follow the 50 Hz. High currents will burn some nerve cells so the
current can't influence your heart anymore (it goes on 'automode'..)
Currents below 10 mA would be reasonably safe I suppose, but I would
not try to hold a 10 mA 220V brrrrrrrrrr

Pieter

 

[Don Kelly]

"Albert L." <albln@verizon.net> wrote in message
news:bl9sd1$1goq$1@f04n12.cac.psu.edu...

I agree.

From a table taken from the "Handbook of Electrical Hazards and Accidents"
published by CRC (1995)

Perception levels in Hand. For DC: 5.2 mA. For 60Hz: 0.4 mA
Painful shock (control not lost) DC: 62 mA. For 60Hz: 9 mA
etc.

Albert

--------------
Thank you. I have AC figures which differ somewhat from yours - for
exapmple perception at 1.1mA ,secondary (paiinful shock)2mA and Let-go 9mA
However, these are all 0.5% probability levels for an adult male so the 50%
probability level would be considerably higher -in the range you give. I'm
sorry that I can't give the source I used but I think it was the EPRI high
voltage book.
--
Don Kelly
dhky@peeshaw.ca
remove the urine to answer