Man grabs high voltage wire while on top of train..... does not end well

[Sea Moose]

Once i did a job in a warehouse that was being used a a clan lab. THere wiring there was extremely poor.

Do you guys have a MEN system in the us or is the Earth provided by the power supplier

 

[Mr. Lennon]

I just watched the video before reading the rest of this thread. Wow...was not expecting that.

 

[Mark R]

Originally posted by: Sea Moose
Ok, we can apply ohhms law.

Voltage = 750
Resistance = 500ohms If charcol gary is all hot and sweaty
Resistance = 10,000 if charcol gary is dry


Resistance is a variable, as i mentioned several times it all depends on how sweaty he is body fat etc etc etc


http://van.physics.illinois.edu/qa/listing.php?id=6793

The resistance here is the internal resistance - skin resistance is irrelevant at the voltage level here (there can be no doubt that the voltage here is 25 kV AC), as it provides no useful dielectic barrier at that voltage. It's certainly not 750 VDC, as that is used only on 3rd rail systems in India - not overhead cables.

OK, perhaps I underestimated the total resistance a little. The resistance across the torso is about 50 ohms - with limbs being about 200 ohms each. This gives a typical internal resistance of somewhere between 300-700 ohms.

Regardless, the current flow here is clearly very high - high double figures at least, low triple figures. Just look at the size and brightness of the arc - it's so bright that it confuses the camera in to dimming the rest of the picture - in other words it's far brighter than direct sunlight falling on the surround scenary. The arc is like an arc welder expcept the arc is 8 feet long and 3 feet wide. Last time I used a 3 kW arc welder, I could get an arc maybe 1/4 inch long, by 1/16 inch wide.

The amount of power being dissipated here is clearly hundreds to thousands of times more than a typical arc welder.

Again, when was the last time you cooked some bacon or burgers on an electric range. How long does it take a 4 kW element to bring itself and a pan up to cooking temperature? Minutes. This guy's entire body was reduced to a smoldering lump of charcol in milliseconds. Do you really regard (750 V * 1.5 A) 10 kW as a reasonable estimate of the power flowing in this scenario?

 

[Sea Moose]

Originally posted by: Mark R

Originally posted by: Sea Moose
Ok, we can apply ohhms law.

Voltage = 750
Resistance = 500ohms If charcol gary is all hot and sweaty
Resistance = 10,000 if charcol gary is dry


Resistance is a variable, as i mentioned several times it all depends on how sweaty he is body fat etc etc etc


http://van.physics.illinois.edu/qa/listing.php?id=6793

The resistance here is the internal resistance - skin resistance is irrelevant at the voltage level here (there can be no doubt that the voltage here is 25 kV AC), as it provides no useful dielectic barrier at that voltage. It's certainly not 750 VDC, as that is used only on 3rd rail systems in India - not overhead cables.

OK, perhaps I underestimated the total resistance a little. The resistance across the torso is about 50 ohms - with limbs being about 200 ohms each. This gives a typical internal resistance of somewhere between 300-700 ohms.

Regardless, the current flow here is clearly very high - high double figures at least, low triple figures. Just look at the size and brightness of the arc - it's so bright that it confuses the camera in to dimming the rest of the picture - in other words it's far brighter than direct sunlight falling on the surround scenary. The arc is like an arc welder expcept the arc is 8 feet long and 3 feet wide. Last time I used a 3 kW arc welder, I could get an arc maybe 1/4 inch long, by 1/16 inch wide.

The amount of power being dissipated here is clearly hundreds to thousands of times more than a typical arc welder.

Again, when was the last time you cooked some bacon or burgers on an electric range. How long does it take a 4 kW element to bring itself and a pan up to cooking temperature? Minutes. This guy's entire body was reduced to a smoldering lump of charcol in milliseconds. Do you really regard (750 V * 1.5 A) 10 kW as a reasonable estimate of the power flowing in this scenario?

I am not estimating i am applying the basic laws of electricity. It doesnt matter if its lighting an electric range hood or a human. Same rules apply.

I am sick of working it out for you guys here is the calculator to make it simple for you:
http://ourworld.compuserve.com...ill_Bowden/ohmslaw.htm


You can say "Wow there must have been a thousand amps there" there simply wasnt. Go and work it out using the very simple calculator i have provided.

 

[PlasmaBomb]

Originally posted by: zoiks
So I suppose the current passing through charcoal gary didn't have enough oomph to zap any of the people touching the train?

The current would take the path of least resistance to ground - through the metal of the train, into the wheels and into ground.

It can't get from the wire to the train without going through the dude though.

 

[Mark R]

Originally posted by: Sea Moose
I am not estimating i am applying the basic laws of electricity. It doesnt matter if its lighting an electric range hood or a human. Same rules apply.

You can say "Wow there must have been a thousand amps there" there simply wasnt. Go and work it out using the very simple calculator i have provided.

I've already worked it out. I know ohm's law perfectly well. The problem is that your answers are off by several orders of magnitude, because although you have used the correct law (Ohm's law) you have used badly wrong estimates of both voltage and resistance, giving a nonsense answer.

My original estimate was 100 Ohms - 25 kV / 100 O = 250 A.

Even with my more recent estimate of 300 - 700 Ohms - that's still a current of 35 - 83A; high double figures as I stated. I still think my estimate of 250 A is not ureasonable, although it may be a little to the high side; the human body is a non-ohmic conductor (current is not proportional to voltage) as the apparent resistance falls dramatically as voltage increases. Don't forget that once an arc has ignited, a lot of current will be carried in the air immediately outside the body - calculation of arc currents isn't practical as there are too many factors to consider. However, some figures I seem to remember are that, a 100 A arc has a resistance of about 1 Ohm per cm. So, if the conductor is 2 metres above the train, that would mean a resistance of about 200 Ohms at 100 A which is roughly consistent.

 

[Sea Moose]

Hmmm where do you get your figure of 100ohms?
The sites i looked up gave me a higher resistive figure, and i got my figure off university sites.

If your figure of human resistance of 100ohms is correct then holy fuck.... 250amps!

Please show your sourece that gives 100ohms i think thats way low.


I just did an experiment with my good multimeter i set the meter to ohms and held each probe in a hand. I got a reading of 200kohms i wonder if that is an accurate reading?

 

[Born2bwire]

Originally posted by: Sea Moose
Hmmm where do you get your figure of 100ohms?
The sites i looked up gave me a higher resistive figure, and i got my figure off university sites.

If your figure of human resistance of 100ohms is correct then holy fuck.... 250amps!

Please show your sourece that gives 100ohms i think thats way low.


I just did an experiment with my good multimeter i set the meter to ohms and held each probe in a hand. I got a reading of 200kohms i wonder if that is an accurate reading?

You didn't read his posts at all did you?

 

[Sea Moose]

yes i did

 

[Born2bwire]

Originally posted by: Sea Moose
yes i did

Is English your first or second language then?

 

[PottedMeat]

Originally posted by: Born2bwire

Originally posted by: Sea Moose
yes i did

Is English your first or second language then?

i think he has a problem with the 'non-ohmic' part.

 

[Sea Moose]

everything has a resistive factor. Air has a resistive fact, water everything

 

[Born2bwire]

Originally posted by: Sea Moose
everything has a resistive factor. Air has a resistive fact, water everything

At this point I'm just going to recommend you not work on a project more complicated than a quartz radio. But then again, seeing as how you can build one using a razor blade this may not turn out well either.

 

[Sea Moose]

Originally posted by: Born2bwire

Originally posted by: Sea Moose
everything has a resistive factor. Air has a resistive fact, water everything

At this point I'm just going to recommend you not work on a project more complicated than a quartz radio. But then again, seeing as how you can build one using a razor blade this may not turn out well either.

funny you think i dont know what im talking about, i am an electrician.

Super conductors are non ohmic the human body is simply a variable resistor, as the flesh is blasted open it changes the resistive values.

 

[Born2bwire]

Originally posted by: Sea Moose

Originally posted by: Born2bwire

Originally posted by: Sea Moose
everything has a resistive factor. Air has a resistive fact, water everything

At this point I'm just going to recommend you not work on a project more complicated than a quartz radio. But then again, seeing as how you can build one using a razor blade this may not turn out well either.

funny you think i dont know what im talking about, i am an electrician.

Super conductors are non ohmic the human body is simply a variable resistor, as the flesh is blasted open it changes the resistive values.

Non-ohmic does not mean zero resistance. I weep for the children of tomorrow.

 

[Sea Moose]

Originally posted by: Born2bwire

Originally posted by: Sea Moose

Originally posted by: Born2bwire

Originally posted by: Sea Moose
everything has a resistive factor. Air has a resistive fact, water everything

At this point I'm just going to recommend you not work on a project more complicated than a quartz radio. But then again, seeing as how you can build one using a razor blade this may not turn out well either.

funny you think i dont know what im talking about, i am an electrician.

Super conductors are non ohmic the human body is simply a variable resistor, as the flesh is blasted open it changes the resistive values.

Non-ohmic does not mean zero resistance. I weep for the children of tomorrow.

where did i say that non ohmic means zero resistance?

I said the human body has variable resistance
http://en.wiktionary.org/wiki/variable <-- theres the definiton of what variable is.

 

[arcenite]

Originally posted by: Born2bwire

Originally posted by: Sea Moose

Originally posted by: Born2bwire

Originally posted by: Sea Moose
everything has a resistive factor. Air has a resistive fact, water everything

At this point I'm just going to recommend you not work on a project more complicated than a quartz radio. But then again, seeing as how you can build one using a razor blade this may not turn out well either.

funny you think i dont know what im talking about, i am an electrician.

Super conductors are non ohmic the human body is simply a variable resistor, as the flesh is blasted open it changes the resistive values.

Non-ohmic does not mean zero resistance. I weep for the children of tomorrow.

Keep weeping, because they're going to be managing your health care some day.

 

[Born2bwire]

Originally posted by: arcenite

Originally posted by: Born2bwire

Originally posted by: Sea Moose

Originally posted by: Born2bwire

Originally posted by: Sea Moose
everything has a resistive factor. Air has a resistive fact, water everything

At this point I'm just going to recommend you not work on a project more complicated than a quartz radio. But then again, seeing as how you can build one using a razor blade this may not turn out well either.

funny you think i dont know what im talking about, i am an electrician.

Super conductors are non ohmic the human body is simply a variable resistor, as the flesh is blasted open it changes the resistive values.

Non-ohmic does not mean zero resistance. I weep for the children of tomorrow.

Keep weeping, because they're going to be managing your health care some day.

It's like staring into the abyss and fully comprehending the sheer infinity of emptiness. It makes feel sad, unfulfilled, and slightly bloated.

 

[Sea Moose]

Originally posted by: Born2bwire

Originally posted by: arcenite

Originally posted by: Born2bwire

Originally posted by: Sea Moose

Originally posted by: Born2bwire

Originally posted by: Sea Moose
everything has a resistive factor. Air has a resistive fact, water everything

At this point I'm just going to recommend you not work on a project more complicated than a quartz radio. But then again, seeing as how you can build one using a razor blade this may not turn out well either.

funny you think i dont know what im talking about, i am an electrician.

Super conductors are non ohmic the human body is simply a variable resistor, as the flesh is blasted open it changes the resistive values.

Non-ohmic does not mean zero resistance. I weep for the children of tomorrow.

Keep weeping, because they're going to be managing your health care some day.

It's like staring into the abyss and fully comprehending the sheer infinity of emptiness. It makes feel sad, unfulfilled, and slightly bloated.

Have you thought about jumping into the abysis?

 

[GodlessAstronomer]

Originally posted by: Sea Moose
everything has a resistive factor. Air has a resistive fact, water everything

Do you understand what non-ohmic means? Try this for an experiment (please be careful) - measure the resistance across the contacts on a light bulb while it's cool. Now turn it on, and measure it again. Resistance changes DRAMATICALLY (an order of magnitude or more) when the filament heats up. Similarly for the body. This is what is meant by non-ohmic. Yeah, it's a silly, misleading term.

 

[Born2bwire]

Originally posted by: Sea Moose

Originally posted by: Born2bwire

Originally posted by: arcenite

Keep weeping, because they're going to be managing your health care some day.

It's like staring into the abyss and fully comprehending the sheer infinity of emptiness. It makes feel sad, unfulfilled, and slightly bloated.

Have you thought about jumping into the abysis?

What? No, dude it's a METAPHOR. It's not real. :disgust:

 

[RichUK]

They probably made a curry out of him.

 

[brxndxn]

Originally posted by: RichUK
They probably made a curry out of him.

Probably..

After everything I've seen in documentaries, movies, and read about India, it seems their culture just really does not value human life the way that we do. They pack themselves into horrible conditions and move around in increasing amounts of garbage and filth.. It's sick..

Some places just have too many people.. and not enough to go around.

 

[feralkid]

Originally posted by: brxndxn

Originally posted by: RichUK
They probably made a curry out of him.

Probably..

After everything I've seen in documentaries, movies, and read about India, it seems their culture just really does not value human life the way that we do. They pack themselves into horrible conditions and move around in increasing amounts of garbage and filth.. It's sick..

Some places just have too many people.. and not enough to go around.

Don't hurt yourself falling off your high horse.

:roll:

 

[Whitecloak]

Originally posted by: brxndxn

Originally posted by: RichUK
They probably made a curry out of him.

Probably..

After everything I've seen in documentaries, movies, and read about India, it seems their culture just really does not value human life the way that we do. They pack themselves into horrible conditions and move around in increasing amounts of garbage and filth.. It's sick..

Some places just have too many people.. and not enough to go around.

hahahahaha