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Zap! 240v right through me!

Author	Topic
Flash Full Member Australia 637 Posts	Posted - 26 Mar 2003 : 08:50:30 Sometimes I work in audio, sometimes I'm a producer.... right now I'm a lighting technician. And today i managed to electrocute myself - big time. The show has a rig of 500 odd lights, and one of the globes had blown, so I set about changing it. I opened the lamp, and figured the circuit was live, so I unplugged it - or so I thought. I had actually unplugged another circuit. Unawares, I put my hand inside, and next thing you know....BANG! The light (literally) exploded, and I got 240v straight through my body. Up the right arm (the one changing the bulb), through the chest and up the other arm (which completed the circuit to earth via the truss) All of this while I am six metres off the ground. All I can say is "F**ken OUCH!, god damn that hurt!!!" Half an hour later, once the shock had passed (no pun intended) I was back to normal. Whatever that is..... - - - - - - - - - - - - - A little knowledge is a dangerous thing, but it sure beats a blank stare for starting a conversation. 68k ParaMedic
G4from128k Full Member USA 873 Posts	Posted - 26 Mar 2003 : 08:57:47 Sounds like you really reset your PRAM. What year do you think it is??? Glad you didn't fall out of the sky. Peace, G4From128k by Day: Mild-Mannered Engineer and Trapeze(tm) Artist by Night: Colonel of Truth, Justice, and the Macintosh Way Reserve Officer in 68kMLA Cantankerous Coot Contingent
Trash80toG-4 NIGHT STALKER USA 2899 Posts	Posted - 26 Mar 2003 : 09:30:53 quote: I opened the lamp, and figured the circuit was live, so I unplugged it - or so I thought. I had actually unplugged another circuit. Count your blessings, Flash, you're one LUCKY comrade! Every once in a while the fates deal out a generous dose of "guess it wasn't very smart for me to do that" kinda response conditioning in a deadly serious situation, now you know why electricians treat EVERYTHING they touch as if it were LIVE! jt ™. Trash Hauler: call sign: eight-ball C.O. AC-130H SpecOps 68kMLAAF
bigsadhu Junior Member Cayman Island 462 Posts	Posted - 26 Mar 2003 : 11:05:05 Livin' up to your name eh buddy? Cheers! CC Air Marshall, 605 sQUADRAn "What Microsoft has got in there is a grotesque, badly-documented pile of poo it doesn't fully understand itself." - The Register, 23/8/02
maclover5 LC Doctor/Hot Rodder Australia 5830 Posts	Posted - 26 Mar 2003 : 15:16:39 quote: Livin' up to your name eh buddy? HAR!™ -------------------------- Give your dreams a chance.™ - Apple in the mid '90s Warrior maclover5 68k Macintosh Liberation Army Number of 68ks Liberated: 7
Clinton Full Member USA 700 Posts	Posted - 27 Mar 2003 : 11:33:54 HAR™ I worked as a lighting technichan once, and I was on a truss when a circut went hot, and there was a cable short. One of the socopex cables was not connecting well to it's octopus. The entire system went out in a shower of sparks, and I nearly fell off my truss until I realized that I was isolated from where the incident took place. as it was, it was a pretty good special effect. I know the feeling of being shocked the way you describe though, I discharged a fatmac through my chest, and it kicked me back about ten feet, I figger it took ten years of use off of my ticker too. CCC ;P CCC Commander Promotion: 19 Mar 2003 13:06:30 68k Macs Rescued: 2 Pluses, a 512KE, a Classic II, a Q650, a Q660AV, an SE/30, and a MacII Contraband rescued: Power Computing PowerBase 200, a PM 8600/300, and a PM8500/180 Apple //s rescued: Apple //e
maclover5 LC Doctor/Hot Rodder Australia 5830 Posts	Posted - 27 Mar 2003 : 15:43:00 I once had 240V crawl up my arm when i was unplugging a PC monitor from the monitor end. It was an old one. -------------------------- Give your dreams a chance.™ - Apple in the mid '90s Warrior maclover5 68k Macintosh Liberation Army Number of 68ks Liberated: 7
Flash Full Member Australia 637 Posts	Posted - 27 Mar 2003 : 20:33:29 quote: Livin' up to your name eh buddy? LOL! I never thought of that quote: Sounds like you really reset your PRAM. What year do you think it is??? 1937 cheers Flash! - - - - - - - - - - - - - A little knowledge is a dangerous thing, but it sure beats a blank stare for starting a conversation. 68k ParaMedic
The Lightning Stalker Full Member USA 747 Posts	Posted - 31 Mar 2003 : 20:11:13 It's good to hear you're okay. Those ones through the chest like that are usually the ones that kill. Although I've shocked myself a few times, luckily it's never been -through- the chest. I work with voltages in excess of 1000 sometimes, so I guess that I must have some angels watching over me or something. Probably what happened was that the filament reached out and touched you when it blew. Please, please, when you're working with stuff like this, don't get into a hurry, and don't let anybody rush you or try to push you around to get the job done faster or anything. I remember one time back in my Xenon period I was playing with a camera flash and touched the can and one of the contacts with my thumb and index finger. I got a shock that I surmize was in excess of 380V DC. The only way I can describe it was like little sprites like the ones from Super Mario World running up and down my hand for a fraction of a second. Another time I was experimenting with a glass plate capacitor and hadn't discharged it completely before I'd went to touch part of it. Several seconds before, it had been charged up to about 30 thousand volts and was discharging through a 3/4" spark gap! I don't know what the residual voltage was, maybe around 500 or so, but I did one of those Huagh!! jumps. It was just a little tingle, really, but still, it set my nerves on end. quote: I was back to normal. Whatever that is..... Interesting you should say that, because electric shocks have been used for a long time in electric shock therapy to treat depression. A big one like the one you had will actually make you feel pretty good after a few days. I've just gotten off of an antidepressant, so don't feel alone, we're in this together! The Lightning Stalker Performa 631CD, 7.5.5 LC III, FPU, 20/80/enet, 7.5.5, Mail Server 6400/180 40/1.6G/512k L2/enet/video-in/TV 7600/120 '604/233, 80/1.2G & 1G/512k L2, 9.2.2 (Main Mac) Lady Smith Apples: Apple IIc 5.25" 2 Apple IIe Edited by - The Lightning Stalker on 31 Mar 2003 20:12:35 Edited by - The Lightning Stalker on 31 Mar 2003 20:13:47
raWr Junior Member Tuvalu 491 Posts	Posted - 31 Mar 2003 : 23:22:56 Once, I held a key in my hand, which had a plastic coating (yeah...not the entire key...), and I thought that if I held on to only the plastic part, maybe I wouldn't get zapped. So I touched an electric fence with it. I was wrong. _r
Flash Full Member Australia 637 Posts	Posted - 01 Apr 2003 : 05:36:39 Well, 've been zapped a number of times - the main culprit is the old faithful Par Can (par 64) which has a ceramic in the back that you grab a hold of to 'focus' the lamp. They are notorious for giving shocks! This time is was completely my fault for not checking whether it was live - even though I'd unplugged it. Lack of sleep was definitely a factor, but it was not a case of being hurried about my job - it was (unfortunately) completely my fault for not double checking - a mistake I won't be making for a while (at least a week!) quote: electric shocks have been used for a long time in electric shock therapy to treat depression Ironically the show is called "Get Happy!" ...and look how happy I am! No depression here The good thing about the high voltages (+ 1000v) that you mentioned, is that they are low on amps. All talk and no action (so to speak) - - - - - - - - - - - - - A little knowledge is a dangerous thing, but it sure beats a blank stare for starting a conversation. 68k ParaMedic
MrLynn Junior Member USA 394 Posts	Posted - 01 Apr 2003 : 20:27:04 Not all high voltages are low on amps, I reckon. There's the story about the guy on the bridge over the railroad tracks who established a connection via a saline solution between himself and the electric power cable below. Probably about 600 volts, and plenty of amps, too. /Mr Lynn The dinosaurs became extinct because they didn’t have a space program. --Larry Niven
Trash80toG-4 NIGHT STALKER USA 2899 Posts	Posted - 01 Apr 2003 : 21:12:04 quote: Not all high voltages are low on amps, I reckon. There's the story about the guy on the bridge over the railroad tracks who established a connection via a saline solution between himself and the electric power cable below. Probably about 600 volts, and plenty of amps, too. YOWCH!!!!!!!!! jt ™. Trash Hauler: call sign: eight-ball C.O. AC-130H SpecOps 68kMLAAF
cory5412 68KMLA Comrade-in-Arms USA 4679 Posts	Posted - 01 Apr 2003 : 21:55:40 My uncle was a high voltage lineman a few years back... Let's just say that we're glad he was left handed anyway! (seeing as how the other one seems to be missing) his right arm and leg were amputaged [:'(] needless to say he was creepy to begin with... can you imagine how creepy... after!!! glad you're all right comrade! t'wouldn't be the same without you here... (the sad thing is we would never have known had something worse happened to you) Glad it didn't! Official 68k videographer Official MLA TourGuide
The Lightning Stalker Full Member USA 747 Posts	Posted - 07 Apr 2003 : 19:53:42 quote: The good thing about the high voltages (+ 1000v) that you mentioned, is that they are low on amps. All talk and no action (so to speak) Well, actually, the pulse discharge of the glass plate capacitor I was using is probably well over a thousand amps, but it only lasts a fraction of a second. I don't know if it can kill and I don't intend to find out. I also made a capacitor charger that could charge HV electrolytics like what's in camera flashes to about 1200V. It wouldn't be too hard to receive a fatal shock from those. I've also played with some microwave transformers which are around 1200V also, only 60 Hz AC and some of them can produce 1 amp at that voltage, which can be quite deadly even though it seems small. I've read materials pertaining to this that say anything above 30 milliamps, that's .003 amps can be fatal no matter what the voltage. It's usually the amperage that kills, although you need enough voltage to carry that current deep enough into the skin. Let's say around 80V or so? You can't get fatal a shock from the 12V battery in your car as some people think, although I'm sure most of you in here know better than that. Also it depends on where the shock goes through you. Usually it has to pass near the heart in order to stop it. That's usually what causes death from a shock, is when the heart stops. In some cases when the power is extreme, such as in lightning strikes, the electricity actually can shut down the neurons too. There's all kinds of interesting articles about how people got struck by lightning and go blind and then get struck again and get their sight back! Yes, it can and has struck the same person twice! Don't anybody get curious and try thwowing craft wire or something over those high tension wires that are on the 100' trellises. Those are about 500,000V, a few hundred amps and eager to find a path to the ground. You would probably explode or maybe even vaporize! Just suspending one of those several feet above the ground will cause it to arc. That's why they're so high. Well, I hope somebody finds this interesting because it took too long to type and it's getting late.
danamania Official 68k Muse Australia 1193 Posts	Posted - 07 Apr 2003 : 19:55:08 I joined up ten 9v batteries (the little square ones) then shorted that across my tongue, once. I saw a white flash! dana
maclover5 LC Doctor/Hot Rodder Australia 5830 Posts	Posted - 07 Apr 2003 : 20:27:23 quote: You can't get fatal a shock from the 12V battery in your car as some people think, although I'm sure most of you in here know better than that. I know. I've been shocked by 12V a couple of times. It makes you jump and thats about it. Those myths are made by the same people who think there are high voltages at the back of a TV where you plug stuff in (AV in/out ports, antenna) on a modern TV!!!!! (my mother.....) -------------------------- Give your dreams a chance.™ - Apple in the mid '90s Warrior maclover5 68k Macintosh Liberation Army Number of 68ks Liberated: 7
cory5412 68KMLA Comrade-in-Arms USA 4679 Posts	Posted - 07 Apr 2003 : 21:42:12 you maniac take a picture if you ever do it again Official 68k videographer Official MLA TourGuide
Flash Full Member Australia 637 Posts	Posted - 07 Apr 2003 : 23:46:24 quote: I joined up ten 9v batteries (the little square ones) then shorted that across my tongue, once. I saw a white flash! dana You saw me in white?! Heh heh, those little suckers can give you a nice buzz on their own - let alone ten of them! comments randomly on other replies I've also heard somewhere that less than an amp can kill you. I wonder how that is measured though? I mean, electricity on it's own has no amps until it goes through a resistive load (V=IxR and all that) - so I guess it depends on how well your body conducts? The electricity obviously has a potential amperage which is defined by the voltage, and the power source. I.E. a standard Australian wall socket has the potential to give you a ten amp whack at 240v, but chances are the shock that you're going to get will be somewhat less that ten amps... Well, that's just my hypothesis - I could be wrong.... out of curiousity, does anybody know what they use on electric chairs? - - - - - - - - - - - - - A little knowledge is a dangerous thing, but it sure beats a blank stare for starting a conversation. 68k ParaMedic
maclover5 LC Doctor/Hot Rodder Australia 5830 Posts	Posted - 08 Apr 2003 : 01:24:50 iTHink its about 10000VAC or something. Not sure though. -------------------------- Give your dreams a chance.™ - Apple in the mid '90s Warrior maclover5 68k Macintosh Liberation Army Number of 68ks Liberated: 7 Number of Contraband (PPC) Liberated from the Dumpster: 1
The Lightning Stalker Full Member USA 747 Posts	Posted - 11 Apr 2003 : 09:23:27 quote: I joined up ten 9v batteries (the little square ones) then shorted that across my tongue, once. I saw a white flash! dana I don't know if there's any truth to it, but I've heard rumors that people have had cardiac arrests from just one 9v across the tongue. I can't imagine 10! Especially if they're hooked up in series quote: I've also heard somewhere that less than an amp can kill you. I wonder how that is measured though? I mean, electricity on it's own has no amps until it goes through a resistive load (V=IxR and all that) - so I guess it depends on how well your body conducts? The electricity obviously has a potential amperage which is defined by the voltage, and the power source..E. Very right! Without getting too much into eletronic theory, the more voltage, the easier it is for your body to pass more current. Your body has a pretty high resistance. That's why it takes a higher voltage and/or a large contact are (ie. a puddle of water) in order to pass enough current to be lethal. quote: a standard Australian wall socket has the potential to give you a ten amp whack at 240v, but chances are the shock that you're going to get will be somewhat less that ten amps... Well, that's just my hypothesis - I could be wrong.... You're right. You'll need to go back to Ohm's law you quoted earlier (V=IxR) And just plug in your wall voltage and the resistance of your body and that will tell you about how many amps are going through you. If you increase the voltage, you'll notice that the current will go up, too, which is why it's easer to bite the dust from a higher voltage whack. Like I said before, the resistance of your body will also depend on the area in contact with the wires and to some extent the pressure of that contact. That's why puddles of water are notorious. Most of the resistance is right at the skin because it's the driest spot. Add some saline solution and your resistance will drop like a rock! DC is worse, too because of the "skin effect" associated with AC. Please don't make me get into this! quote: out of curiousity, does anybody know what they use on electric chairs? I think every electric chair is a little different. All I know is that the lights in the prison dim when they throw the switch and the resistive heating starts to cook the occupant. I'm saying around 500v AC maybe? Then those wide straps and probably some salt water to increase conductivity.
Trash80toG-4 NIGHT STALKER USA 2899 Posts	Posted - 11 Apr 2003 : 11:07:29 people = very good conductors people = VERY BAD capacitors YMMV . . . a lot! jt ™. Trash Hauler: call sign: eight-ball C.O. AC-130H SpecOps 68kMLAAF
cory5412 68KMLA Comrade-in-Arms USA 4679 Posts	Posted - 11 Apr 2003 : 20:40:43 HARHAR Let's build the "People PowerSupply" we need people with different ammount of capacitor ability Official 68k videographer Official MLA TourGuide
Flash Full Member Australia 637 Posts	Posted - 12 Apr 2003 : 08:13:31 quote: Let's build the "People PowerSupply" how does that story go...? if you harness the energy expended by ten couples having sex...... A people-power-supply reminds me of The Matrix. You know, where humans are farmed and harvested to provide power for who/whatever it is that created 'the matrix' I'm a bit hazy, was it an alien life form that came to earth in that movie? I remember that they used the sun as an energy source, and when we humans purposely started a nuclear winter to block out the sun they started using us for power instead.... anyhow the bit I find interesting about the whole thing is the concept that you can't grow a human in a tank without occupying the brain..... hmmmm, food for thought - literally! LOL! - - - - - - - - - - - - - A little knowledge is a dangerous thing, but it sure beats a blank stare for starting a conversation. 68k ParaMedic
cory5412 68KMLA Comrade-in-Arms USA 4679 Posts	Posted - 12 Apr 2003 : 22:40:16 I was talking about with the restors and the conductors etc etc.... :glayven: Official 68k videographer Official MLA TourGuide
Flash Full Member Australia 637 Posts	Posted - 13 Apr 2003 : 04:30:51 quote: I was talking about with the resistors and the conductors etc etc.... Yeah, I know you were. I just have an overactive imagination - - - - - - - - - - - - - A little knowledge is a dangerous thing, but it sure beats a blank stare for starting a conversation. 68k ParaMedic
cory5412 68KMLA Comrade-in-Arms USA 4679 Posts	Posted - 13 Apr 2003 : 17:24:13 Oh don't let me stop you... if we can have those people who are thoroughly enjoying themselves :shudders: powering my computers all the time I'm all for it... as long as I'm a few miles away from it all... Official 68k videographer Official MLA TourGuide
The Lightning Stalker Full Member USA 747 Posts	Posted - 13 Apr 2003 : 17:37:54 quote: I was talking about with the restors and the conductors etc etc.... That's okay. It's when they start talking back to you that you need to worry.

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