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

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Oct 27, 2007
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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.

:roll:
 

Sea Moose

Diamond Member
May 12, 2009
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When all is said and done, the guy got wasted

The moral of the story kids is dont use that over head line as a hand hold when riding shot gun on the roof of a train
 

zoiks

Lifer
Jan 13, 2000
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Do you think they're still going to cremate him? The dude's already a rib roast.
 

Jeff122886

Junior Member
Jun 9, 2009
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Originally posted by: Sea Moose
Originally posted by: MrDudeMan
Originally posted by: Quintox
Originally posted by: Sea Moose
Lets put this into perspective.

240v supply with a kettle with a resistance of say 26ohms

ohms law = V/R=I

Therfore 240volts/26ohms = 9amps


The man in the video.

The human body has a resistance of about 50,000 ohms(this varies from person to person)
The voltage on the site says the main line voltage is either 1.5kv DC or 25kV AC.

We can calculate both figures using ohms law.

1 500volts/50 000ohms = .3amps <--- Thats right, less than one amp.

25 000volts/50 000 = .5amps <--- Also less that one amp.



The interesting thing is his power output

When charcol gary is drawing .3amp his power output is 45watts <--- Comparable to a light globe
When charcol gary is drawing .5amp his power output is 12500watts <--- comparable to an air conditioning unit for a small house.

Take this into account

.001amps to 0.01 = threshold of sensation
.01amp to .1amp = painful shock, cannot let go, muscular paralysis, severe shock, breathing difficultys
0.1amps to 0.2 amps = death
0.2amps to 1.0amp = severe burning.




May i remind all to be careful around electricity please. may i also point out that his arms go rigid.

Rubycon, is that you?

(BTW I blanked out on her name and spent 10 minutes searching)

This is wrong since he was undoubtedly sweating. Most of the resistance of a human body is the first layer of skin, but with sweat there is a much lower resistance pathway into the blood. At that point, the resistivity is relatively low, e.g. < 10 ohm cm and it is safe to assume it is traveling through his blood as it is either DC or low frequency AC. The total series resistance of the human body at that point would be far, far less than 50,000 ohms. The currents in this video are definitely higher than a few amps.

Also, the body isn't an ohmic material. After the first bit of current started shocking him, his resistance changed and even more current was drawn. It's similar to how a lightbulb draws thousands of amps and quickly is reduced to something manageable after the resistance of the filament changes due to heat. I wouldn't be surprised if hundreds or thousands of amps were going through him before the fault protection stopped it. Burned or blistered skin has basically negligible resistance and it only takes a few microseconds for that to happen. The current was hitting him for at least a few hundred milliseconds, well beyond what would be necessary to blister his enter body. He was basically a short to ground after that point.

Actually ohms law applies to everthing, you can calculate lightning using ohms law. We know the voltage, we can only theorise his resistance, and then the basic ohms law can be applied.

Current = Voltage/Resistance

Also i forgot to mention that the human body can act as a capacitor, cool huh.

I am not sure why there were two flashes, my bro in law in an electrical engineer i will run it past him.

I am an electrical engineer, i was working for the power company and my only assumption why it sparked twice is due to a recloser in the circuit. they use them in overhead lines when squirrels short out circuits and such. it pretty much tries to automatically reclose the circuit a few seconds after the short to prevent the power going out until someone gets there. it will try a few times, if it shorts a few times when it tries it will turn off until someone mechanically flips it back on.

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

Jeff122886

Junior Member
Jun 9, 2009
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also quoted from the IRFCA(indian railways fan club)


Single system (AC): The overhead catenary is fed electricity at 25kV AC (single-phase) from feeding posts which are positioned at frequent intervals alongside the track. The feeding posts themselves are supplied single-phase power from substations placed 35-60km apart along the route. The substations are spaced closer (down to 10-20km) in areas where there is high load / high traffic. (These substations in turn are fed electricity at 132kV AC or so from the regional grids operated by state electricity authorities.) A Remote Control Centre, usually close to the divisional traffic control office, has facilities for controlling the power supply to different sections of the catenaries fed by several substations in the area.

that line was running at 25kV AC.
so if he was really sweaty, which he most likely was, his body resistance was very very low and the current was very high.
 

Q

Lifer
Jul 21, 2005
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Quote from a comment on that site
Obviously he didn't understand the physics of electricity. It arced on him. He was actually only threatening to touch it. His hand, if you look closely was only about six inches or more from the wire

I don't think the video shows that clearly so I don't know if I believe it, but can / could that of happened?
 

spidey07

No Lifer
Aug 4, 2000
65,469
5
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Originally posted by: Quintox
Quote from a comment on that site
Obviously he didn't understand the physics of electricity. It arced on him. He was actually only threatening to touch it. His hand, if you look closely was only about six inches or more from the wire

I don't think the video shows that clearly so I don't know if I believe it, but can / could that of happened?

Absolutely. Voltage that high can arc a REALLY long distance.

http://www.youtube.com/watch?v=6Ll8D8G_Nek
 

KevinH

Diamond Member
Nov 19, 2000
3,110
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Originally posted by: spidey07
Originally posted by: Quintox
Quote from a comment on that site
Obviously he didn't understand the physics of electricity. It arced on him. He was actually only threatening to touch it. His hand, if you look closely was only about six inches or more from the wire

I don't think the video shows that clearly so I don't know if I believe it, but can / could that of happened?

Absolutely. Voltage that high can arc a REALLY long distance.

http://www.youtube.com/watch?v=6Ll8D8G_Nek

Holy shit.
 

IGBT

Lifer
Jul 16, 2001
17,974
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Originally posted by: alkemyst
Originally posted by: Sea Moose
Originally posted by: IGBT
General Information
Fleet Size - 22
Type - Articulated w/3 trucks
Doorways per car - 4 per side
Capacity (Seated) - 70 (approx.)
Capacity (w/Standees) - 155 (approx.)
Capacity (Crush Load) - 250 (approx.)
Features - HVAC, Automated Announcements

Technical Information
Length - 88-94 feet
Width - 8' 8 3/4"
Height - 12' 5"
Interior Headroom - 6' 7"
Interior Floor Height - 14" above top of rail
Weight - 105,000 lbs. empty
Gauge - 4' 8 1/2" (Standard)
<<<Operating Voltage - 750 VDC
Traction Motors - 4 AC motors per car
Traction Controls - AC Drive
Braking - Re-generative-Dynamic/Friction/TrackBrake
Average Acceleration - 3 mphps
Average Deceleration - 3 mphps (Normal) - 5 mphps (Emergency)
Max Speed - 55 mph
Carbody Construction - Corten Steel

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

therfore

I=V/R

volts/Resistance=current
750/500= 1.5amp
750/10,000=.075amp

The human body cannot draw 250amps.

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

Operating voltage has nothing to do with what is being carried on the line supplying it. There are probably multiple trains on the one feed.

3rd rail and overhead power substations go thru great lengths to maintain line voltage. Modern heavy rail transit and LRV's have strict line voltage requirements and will take them selves off line if an overvoltage condition is detected.

 

Mark R

Diamond Member
Oct 9, 1999
8,513
16
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Originally posted by: KevinH
Originally posted by: spidey07
Absolutely. Voltage that high can arc a REALLY long distance.

http://www.youtube.com/watch?v=6Ll8D8G_Nek

Holy shit.

That's not meant to happen though. Quite a cool video though, you can see one of the SF6 breaker (grey horizontal rods towards the right of the picture) malfunction. It's actually the right breaker that malfunctions (doesn't disconnect). Unfortunately, this is a 500 kV line, but the SF6 breakers are only 250 kV - so it needs two operating simultaneously to disconnect the circuit safely. With only one (the one on the left), the electricity just goes straight round it.

Because the SF6 breakers haven't disconnected the power, the safety mechanical disconnect switch arcs causing the massive Jacob's ladder type effect (this switch isn't designed to switch power - just to disconnect an already dead circuit).

The story of how this vid came about is quite interesting. The switch was triggered one day, but a monitoring circuit reported a fault; power continued to flow through for several seconds, even though the switch had reached the 'off' position. An engineering team was sent out to investigate, and they rigged a video camera up while they operated the switch remotely, to look for malfunctions. I don't think they were expecting this.