Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 03-09-2011, 04:17 PM   #1
Member
 
Join Date: Jun 2010
Location: se
Posts: 1,327
Rewards Points: 520
Default

Question for a really smart electrician/physicist


Not really related to a DIY project, but was hoping to get an answer just the same for this......heres a link to a story where a guy apparantly was "saved" from a 14,000 V jolt of electricity from wearing rubber shoes.

:http://www.villagevoice.com/2010-04-...-snuff-film/3/

I always understood that say, rubber shoes wont save you from a jolt of lightning, so then could we attribute this guy as having been saved by his rubber shoes???

Lightning has about 1 billion volts. also, has 20,000 amps -300,000 amps. Maybe thats the difference, guys??

Thanks!

noquacks is offline   Reply With Quote
Old 03-09-2011, 04:52 PM   #2
Newbie
 
Join Date: Mar 2011
Posts: 5
Rewards Points: 10
Default

Question for a really smart electrician/physicist


To me it seems that the metal cage he was in was grounded, so the electricity was channeled away from him and safely to ground. From what I picked up from the story, the generator blew when it short-circuited on the "condor" thing. Even barefoot, he would have felt a small jolt. But that's the whole purpose of grounding: to channel a fault safely away from a person and to ground.

fsae0607 is offline   Reply With Quote
Old 03-09-2011, 04:58 PM   #3
I=E/R
 
a7ecorsair's Avatar
 
Join Date: May 2010
Location: Minnesota
Posts: 2,052
Rewards Points: 1,000
Default

Question for a really smart electrician/physicist


Have you ever wondered why birds can sit on a high voltage line and not get shocked to death? Same situation and the shoes had no part.
a7ecorsair is offline   Reply With Quote
Old 03-09-2011, 05:04 PM   #4
Experienced
 
Jackofall1's Avatar
 
Join Date: Dec 2010
Location: Southern Michigan
Posts: 2,822
Rewards Points: 2,000
Default

Question for a really smart electrician/physicist


Yes, I would bet what did save him, was the rubber tires on the condor, not the soles of his boots, whole different story had things been wet.

Ever see the story on how they service the high tension wires from a helicopter, absolutely wild, but they connect a platform from the helicopter to the wire, the service man works on the platform while the helo is hovering at the same elevation and the other side of the platform connected to the wire.

The only thing they worry about at that point is static discharge.

Mark
__________________
When its all said and done there is usually more said than done
Jackofall1 is offline   Reply With Quote
Old 03-09-2011, 06:08 PM   #5
Member
 
Join Date: Jan 2011
Posts: 104
Rewards Points: 77
Default

Question for a really smart electrician/physicist


Any time there is more than one path to ground, electricity will always seek the path of least resistance.
davido30093 is offline   Reply With Quote
Old 03-09-2011, 06:16 PM   #6
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,968
Rewards Points: 2,032
Default

Question for a really smart electrician/physicist


Possibilities:

1. Currrent would have gone through Jason Welin's hands, electrocuted him, and exited via his feet and down the metal frame of the cherrypicker (condor) except his rubber shoes stopped that current path.

2. Current went directly to the frame of the cherrypicker and Jason Welin was not in the path of least resistance.

3. Because the earth is not that great a conductor, different spots on the ground surface were at varying voltage potentials up to about 14,400 volts maximum difference once contact was made up above and given that various pieces of movie equipment sat here and there on the ground.

4. The 120 volt and/or 240 volt movie lights and equipment were fried by the 14,400 volt line current coming through the movie equipment and jumping through the insulation of the 120 and 240 volt wires attached.

5. John Lamensdorf was killed and Brian Streem was injured from the current from the 14,400 volt line coming through movie equipment they were holding on to and/or movie electrical lines near them together with the differing electric potentials of the exact spots of the ground on which they were standing.

6. At that time there was no danger related to the current from the generator per se. The entire problem was caused by accidental touching of a 14,400 volt electrical line nearby that was not part of the equipment and not part of an attempted tie-in.
__________________
Forget super sized fries. The Washington Redskins could promote healthy eating with First Lady Obama by choosing a (red skinned) turnip for a mascot.

Last edited by AllanJ; 03-09-2011 at 06:49 PM.
AllanJ is offline   Reply With Quote
Old 03-09-2011, 06:55 PM   #7
Member
 
Join Date: Aug 2010
Location: Maryland
Posts: 300
Rewards Points: 262
Default

Question for a really smart electrician/physicist


amperage is what kills you and stops your heart, the amperage that did go through him didn't go over his heart. He's lucky as anything, that said.
MLMIB is offline   Reply With Quote
Old 03-09-2011, 07:00 PM   #8
Licensed electrician
 
Join Date: Sep 2007
Location: Maryland
Posts: 7,811
Rewards Points: 2,420
Default

Question for a really smart electrician/physicist


Quote:
Originally Posted by davido30093 View Post
Any time there is more than one path to ground, electricity will always seek the path of least resistance.
I really wish people would understand that electricity takes ALL paths. It is just in proportion to the resistance.
__________________
Answers based on the National Electrical Code. Local amendments may apply. Check with your local building officials.
Jim Port is offline   Reply With Quote
The Following 3 Users Say Thank You to Jim Port For This Useful Post:
CheapCharlie (03-10-2011), mpoulton (03-12-2011), Saturday Cowboy (03-10-2011)
Old 03-09-2011, 07:04 PM   #9
Member
 
Join Date: Jun 2010
Location: se
Posts: 1,327
Rewards Points: 520
Default

Question for a really smart electrician/physicist


You guys are great! Thanks! So, I didnt get it from the article, but was there mention of the amperage? Would that compare to that of a lightning bolt which is like, 3000,000 amps? I doubt it, huh......

I mean, this guy keeps bringing up how his buddy was "saved" once in a parking lot when a bolt of lightning hit a car just next to him, knocking him down, yet unhurt. And when the paramedic told him his sneakers saved him thats when I told him the medic better stick to his profession as sneakers will never stop a bolt of 1 billion volts . Now, because of this article, my buddy feels it vindicates his belief that rubber soles are a life saver in lightning.......

Last edited by noquacks; 03-09-2011 at 07:14 PM.
noquacks is offline   Reply With Quote
Old 03-09-2011, 07:13 PM   #10
Member
 
Join Date: Jun 2010
Location: se
Posts: 1,327
Rewards Points: 520
Default

Question for a really smart electrician/physicist


Quote:
Originally Posted by a7ecorsair View Post
Have you ever wondered why birds can sit on a high voltage line and not get shocked to death? Same situation and the shoes had no part.
Thanks. I understand about the Faraday Cage Effect, but how does the birds ona wire work?
noquacks is offline   Reply With Quote
Old 03-09-2011, 08:46 PM   #11
I=E/R
 
a7ecorsair's Avatar
 
Join Date: May 2010
Location: Minnesota
Posts: 2,052
Rewards Points: 1,000
Default

Question for a really smart electrician/physicist


Quote:
Originally Posted by noquacks View Post
how does the birds ona wire work?
Voltage is a difference of potential (EMF) between two points and since the bird is sitting on the point of reference there is no difference of potential. If I had the bird hold one probe from a meter with a 10 megohm input impedance in his beak and I grounded the other and then got the bird to land on a 100,000 volt transmission line, it would give him a darn good shock. He would feel 10 milliamps of current. So, as long as you don't measure the bird's voltage he will be just fine.
a7ecorsair is offline   Reply With Quote
Old 03-09-2011, 09:06 PM   #12
Member
 
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 6,968
Rewards Points: 2,032
Default

Question for a really smart electrician/physicist


Quote:
Originally Posted by Jim Port View Post
I really wish people would understand that electricity takes ALL paths. It is just in proportion to the resistance.
Instead of "path of least resistance" I should say that at the time there was no path through Jason Welin with a resistance low enough that enough milliamperes would flow so as to electrocute him. One example of such a path: From the 14,400 volt electric line to the movie prop to its guy wire to Jason's hand holding the other end of the guy wire through Jason to his rubber shoe soles to the floor of the cherry picker cab down the cherry picker then along the outside of the wet tire of the cherry picker vwhicle and into the mud.

Meanwhile some current from the 14,400 volt line may have gone through the movie prop, through the insulation of some 120 volt wires strung through the movie prop for lights, through the generator system, and through the insulation of other wires in a movie lamp post that John Lamensdorf happened to be leaning on. The current went through his body, electrocuting him, and down through his wet leather shoes into the ground where he was standing.
__________________
Forget super sized fries. The Washington Redskins could promote healthy eating with First Lady Obama by choosing a (red skinned) turnip for a mascot.

Last edited by AllanJ; 03-09-2011 at 09:21 PM.
AllanJ is offline   Reply With Quote
Old 03-10-2011, 11:27 AM   #13
Member
 
Join Date: Jan 2011
Posts: 104
Rewards Points: 77
Default

Question for a really smart electrician/physicist


Quote:
I really wish people would understand that electricity takes ALL paths. It is just in proportion to the resistance.
That is exactly right, but when one path has very low resistance relative to the other paths, MOST of the current will go through the path of least resistance.
davido30093 is offline   Reply With Quote
Old 03-10-2011, 04:59 PM   #14
Member
 
Join Date: Jun 2010
Location: se
Posts: 1,327
Rewards Points: 520
Default

Question for a really smart electrician/physicist


Thanks, again, guys. You have explained it well, and promptly. I appreciate it very much.
You have proven yous are really smart electricians as well as physicists!!

Last edited by noquacks; 03-10-2011 at 05:02 PM.
noquacks is offline   Reply With Quote
Old 03-11-2011, 10:51 PM   #15
WDR
Member
 
Join Date: Aug 2010
Posts: 94
Rewards Points: 75
Default

Question for a really smart electrician/physicist


The amperage and voltage Both matter, a car battery can deliver over 200 amps. That amperage is more than enough to kill you. But I have never heard of anyone electrocuted by a car battery. The voltage is low enough that the resistance of skin stops the electricity.

WDR is offline   Reply With Quote
The Following User Says Thank You to WDR For This Useful Post:
noquacks (03-12-2011)
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
3 Phase meter socket question a320200 Electrical 4 12-11-2009 01:45 AM
An unasked question is the only dumb question jackie treehorn Kitchen & Bath Remodeling 1 09-20-2009 09:24 PM
A question about water preassure. reasonforseason Plumbing 5 04-14-2009 05:36 PM
Soffit venting vs. DCI Smart Vent JDPII Roofing/Siding 1 02-28-2009 09:42 PM
Basement Renovation Question KUIPORNG Remodeling 234 08-26-2008 09:19 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.