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#1
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Up to around 3000v DC off a local generator IIRC (thus the dimming of
the prison lights as seen in many films is a load of old cobblers). There was a DC v AC competition involving the public killing of an elephant in the early days of deciding the "best" way to fry people; prior to that Thomas Edison "perfected" his AC system by killing numerous cats and dogs in experiments :- http://www.ccadp.org/electricchair.htm The local SPCA used to electrocute animals. Then they went to gassing, now it's the needle. -- Cheers Roger T. Home of the Great Eastern Railway at:- http://www.highspeedplus.com/~rogertra/ Latitude: 48° 25' North Longitude: 123° 21' West |
#2
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On 3 Apr, 06:02, "Roger T." wrote:
Up to around 3000v DC off a local generator IIRC (thus the dimming of the prison lights as seen in many films is a load of old cobblers). There was a DC v AC competition involving the public killing of an elephant in the early days of deciding the "best" way to fry people; prior to that Thomas Edison "perfected" his AC system by killing numerous cats and dogs in experiments :- http://www.ccadp.org/electricchair.htm The local SPCA used to electrocute animals. *Then they went to gassing, now it's the needle. -- Cheers Roger T. Home of the Great Eastern Railway at:-http://www.highspeedplus.com/~rogertra/ Latitude: *48° 25' North Longitude: *123° 21' West When we lived next to a 750v 3rd rail line, in the days when you could have an allotment on the bank, our cat used to wander on to the tracks quite regularly until one day, we assume, his tail swished against the rail. When we finally caught up with him, there was a horrible smell of singed fur and a bald patch on his tail. He kept away from the rails after that. I always understood that AC killed by high voltages but threw you off so you might survive, but DC killed with low voltages because you just stuck there! MaxB |
#3
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![]() From: "MaxB" Subject: Crossing London tube tracks Date: 03 April 2008 08:52 On 3 Apr, 06:02, "Roger T." wrote: Up to around 3000v DC off a local generator IIRC (thus the dimming of the prison lights as seen in many films is a load of old cobblers). There was a DC v AC competition involving the public killing of an elephant in the early days of deciding the "best" way to fry people; prior to that Thomas Edison "perfected" his AC system by killing numerous cats and dogs in experiments :- http://www.ccadp.org/electricchair.htm The local SPCA used to electrocute animals. Then they went to gassing, now it's the needle. -- Cheers Roger T. Home of the Great Eastern Railway at:-http://www.highspeedplus.com/~rogertra/ Latitude: 48° 25' North Longitude: 123° 21' West When we lived next to a 750v 3rd rail line, in the days when you could have an allotment on the bank, our cat used to wander on to the tracks quite regularly until one day, we assume, his tail swished against the rail. When we finally caught up with him, there was a horrible smell of singed fur and a bald patch on his tail. He kept away from the rails after that. I always understood that AC killed by high voltages but threw you off so you might survive, but DC killed with low voltages because you just stuck there! MaxB Reminds me of a time, hundreds of years ago, when I was about 10, and my dad was repairing the electric iron. He had it in bits, looking for why it didn't get hot any more. After he had put it back together he plugged it in and while he was putting his tools away, asked me to touch it. Being extremely naive I assumed that he wanted to know if it was getting hot or not. So I touched it. "No. it' still cold", I said. "Oh, but you have sports shoes on, take one off", he said. I really couldn't imagine how this was going to affect my appreciation of how hot or cold the iron was, but I took a shoe off and felt the iron again. "Zappaaloo !!!" I wasn't thrown across the room, I simply couldn't let go! Dad pulled the plug out of the socket, and more in frustration than sorrow, complained that obviously the iron still wasn't fixed. All this is true, whatever that means. |
#4
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On Thu, 3 Apr 2008 07:42:49 +0000, Bill Again wrote
Reminds me of a time, hundreds of years ago, when I was about 10, and my dad was repairing the electric iron. He had it in bits, looking for why it didn't get hot any more. After he had put it back together he plugged it in and while he was putting his tools away, asked me to touch it. Being extremely naive I assumed that he wanted to know if it was getting hot or not. So I touched it. "No. it' still cold", I said. "Oh, but you have sports shoes on, take one off", he said. I really couldn't imagine how this was going to affect my appreciation of how hot or cold the iron was, but I took a shoe off and felt the iron again. "Zappaaloo !!!" I wasn't thrown across the room, I simply couldn't let go! Dad pulled the plug out of the socket, and more in frustration than sorrow, complained that obviously the iron still wasn't fixed. All this is true, whatever that means. I guess it means that you quickly gained a *real* appreciation of what electricity can do - and you've remembered it all these years! |
#5
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On Thu, 3 Apr 2008 08:55:44 +0000, Stimpy wrote:
On Thu, 3 Apr 2008 07:42:49 +0000, Bill Again wrote Reminds me of a time, hundreds of years ago, when I was about 10, and my dad was repairing the electric iron. He had it in bits, looking for why it didn't get hot any more. After he had put it back together he plugged it in and while he was putting his tools away, asked me to touch it. Being extremely naive I assumed that he wanted to know if it was getting hot or not. So I touched it. "No. it' still cold", I said. "Oh, but you have sports shoes on, take one off", he said. I really couldn't imagine how this was going to affect my appreciation of how hot or cold the iron was, but I took a shoe off and felt the iron again. "Zappaaloo !!!" I wasn't thrown across the room, I simply couldn't let go! Dad pulled the plug out of the socket, and more in frustration than sorrow, complained that obviously the iron still wasn't fixed. All this is true, whatever that means. I guess it means that you quickly gained a *real* appreciation of what electricity can do - and you've remembered it all these years! My grandfather (RIP, but not of electrocution) in the United States used to test a light socket by wetting his finger and sticking it into the socket. As he was wearing rubber-soled shoes, and took care not to ground himself elsewhere, he only got a tingle. I wouldn't recommend it as a fool-proof method. -- Chris Hansen | chrishansenhome at btinternet dot com Kevin: "I'm a atheist and I don't want a pervy priest saying any last rites over me!" Bob: "Cross-posting top-posters go straight to hell anyway ..." from alt.obituaries |
#6
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On Wed, 2 Apr 2008 23:52:23 -0700 (PDT), MaxB
wrote: On 3 Apr, 06:02, "Roger T." wrote: Up to around 3000v DC off a local generator IIRC (thus the dimming of the prison lights as seen in many films is a load of old cobblers). There was a DC v AC competition involving the public killing of an elephant in the early days of deciding the "best" way to fry people; prior to that Thomas Edison "perfected" his AC system by killing numerous cats and dogs in experiments :- http://www.ccadp.org/electricchair.htm The local SPCA used to electrocute animals. *Then they went to gassing, now it's the needle. When we lived next to a 750v 3rd rail line, in the days when you could have an allotment on the bank, our cat used to wander on to the tracks quite regularly until one day, we assume, his tail swished against the rail. When we finally caught up with him, there was a horrible smell of singed fur and a bald patch on his tail. He kept away from the rails after that. I always understood that AC killed by high voltages but threw you off so you might survive, but DC killed with low voltages because you just stuck there! There's a lot of pub science involved. Whether you get thrown away or hang on more likely depends on which muscles are affected and/or whether being thrown away is actually the result of a reflex reaction to a shock that might not actually be life-threatening. Either are equally harmful from the POV of burns (which can be internal and follow bones) caused by the passage of enough current through the body distinct from any effect upon the heart's rhythm. |
#7
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On Thu, 03 Apr 2008 20:31:30 +0100, Charles Ellson wrote:
Whether you get thrown away or hang on more likely depends on which muscles are affected Aye all muscles work in pairs and one is normally stronger than the other. Think of the bicep to bend your arm at the elbow and triceps to straighten it. If the current is stimulating the stronger muscle you end up being "locked on". and/or whether being thrown away is actually the result of a reflex reaction to a shock that might not actually be life-threatening. Being thrown across the room is again a function of massively stimulating the muscles, you involuntarily throw yourself across the room. -- Cheers Dave. |
#8
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In message et, Dave
Liquorice writes On Thu, 03 Apr 2008 20:31:30 +0100, Charles Ellson wrote: Whether you get thrown away or hang on more likely depends on which muscles are affected Aye all muscles work in pairs and one is normally stronger than the other. Think of the bicep to bend your arm at the elbow and triceps to straighten it. If the current is stimulating the stronger muscle you end up being "locked on". and/or whether being thrown away is actually the result of a reflex reaction to a shock that might not actually be life-threatening. Being thrown across the room is again a function of massively stimulating the muscles, you involuntarily throw yourself across the room. Been there and done that. It was a small room about 12' X 12 and I was sitting at a bench on onside when I caught mains from the back of a toggle switch. Apparently I pushed my self away from the bench so hard that I hit the wall on the far side of the room. I don't recall a lot about it, apart from being scared stiff for a second or so as I realised what was happening. I woke up sitting on the floor, colleagues reckoned it was quite spectacular!! -- Bill |
#9
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me wrote:
Hence the advise.... Test if a wire is live by touching it to the BACK of the hand. The muscle action is then to throw your hand away Better still, test with a meter! |
#10
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On Sat, 05 Apr 2008 23:59:50 +0100, Bruce Fletcher (Stronsay, Orkney)
wrote: Test if a wire is live by touching it to the BACK of the hand. The muscle action is then to throw your hand away Better still, test with a meter! A meter can be misleading if it has a high impedance, as many modern meters do. It'll measure voltages induced into the wire that are not actually there if you apply even a small "load". -- Cheers Dave. |
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