# How deadly is 120v



## Subzer0IsGG (Sep 14, 2012)

Discuss.
I already know its the ma that kills, and factors like compromised natural resistance will increase the ma. But lets be honest, how dangerous is it really...


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## big vic (Jan 23, 2012)

Too dangerous for you


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## Going_Commando (Oct 1, 2011)

Before I have a cup of coffee every morning, I slap 120v across my nipples. Beats the hell out of caffeine!



































:jester:


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## wildleg (Apr 12, 2009)

apparently more people die from 120 than anything else (in the US), so . . . I guess it's deadly enough.


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## knowshorts (Jan 9, 2009)

120 is the most deadly because people don't respect it like they do higher voltages. Too much of the attitude "ah, it's only 120".


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## Tsmil (Jul 17, 2011)

wildleg said:


> apparently more people die from 120 than anything else (in the US), so . . . I guess it's deadly enough.


Statistics like that mean nothing. Of coarse more people die from 120 than anything else. I haven't seen many ( or any) homes wired with 480 or 600.


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## RGH (Sep 12, 2011)

under the right conditions...120v @ 20 amps...is 200x more than what is nessesary to kill the avg human....again given the worst case senerio...bare feet, wet surface, bare skin contact.....


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## wildleg (Apr 12, 2009)

Tsmil said:


> Statistics like that mean nothing. Of coarse more people die from 120 than anything else. I haven't seen many ( or any) homes wired with 480 or 600.


I beg to differ. In the context of "Is 120v really dangerous" I think that the statistics say everything. If the fact that more people die from it than any other voltage isn't enough, then please elaborate as to what, exactly, is enough.


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## Tsmil (Jul 17, 2011)

wildleg said:


> I beg to differ. In the context of "Is 120v really dangerous" I think that the statistics say everything. If the fact that more people die from it than any other voltage isn't enough, then please elaborate as to what, exactly, is enough.


No argument that 120 is deadly. Just that the statistic is skewed. More people die from 120 because more people have access to it. 

Now if you were to compare the ratio of how many people contacted 120 and died and compared that to the number of people who contacted 480 and died you would have a statistic that is comparable.

More people die in car accidents than boating accidents. Why? Maybe because so many more people drive than boat. 

Is 120 actually dangerous? You bet your a$$ it is. 

As a youngster, my father taught me a golden rule. Always treat ladders and electricity like a beautiful woman. Always respect them and never turn your back on them.


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## RGH (Sep 12, 2011)

..how much is enough???...7 to 10 milli ampes will stop your heart....thats thousands of 1 amp.... .007 amps ...your instructors should cover this stuff in school....one of the reasons your choice of foot wear is very important in this trade...


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## eejack (Jul 14, 2012)

Subzer0IsGG said:


> how dangerous is it really...


It can kill you. So pretty dangerous.


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## Subzer0IsGG (Sep 14, 2012)

mmmmm. Great responses. Thanks guys.


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## Speedy Petey (Jan 10, 2007)

Subzer0IsGG said:


> I already know *its the ma that kills*,


Please explain what you think this means.


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## Subzer0IsGG (Sep 14, 2012)

Speedy Petey said:


> Please explain what you think this means.


1 - 5 a "tingling" sensation
5 - 10 mAdiscomfort, pain
10 - 20 mAinvoluntary muscle contraction, ventricular fibrillation
20 - 100 mAparalysis, loss of breathing, heart stoppage

Ma = milliamperes

I = E/R 
Current is directionally proportionally to voltage etc.

Not sure why your asking? I'm an electrician not a "home owner"
*


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## Subzer0IsGG (Sep 14, 2012)

Can't edit posts? Proportionate. Not lly...I'm new


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## Speedy Petey (Jan 10, 2007)

Subzer0IsGG said:


> Not sure why your asking? I'm an electrician not a "home owner"
> *


I hear this all the time and I wonder what folks think it means. I have even heard licensed electrician referring to the service size as a factor in the danger level. 
So when I hear "_it's the amps that kill you_" I wonder what people think this means. Almost like the voltage is less important. 

It is the current flowing through the body that counts, but it's the voltage that gets it there. It's the voltage that is more likely to kill you. The higher the voltage the more lethal the amps are likely to be, and the more likely you are to get burned, which is as much, or more, of a danger as being shocked.


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## Big John (May 23, 2010)

My problem with the "it's the current that kills you" saying is that while technically true, it seems very misleading: The vast majority of circuits the average Joe encounters can source enough current to be deadly, so it is the voltage that determines the ultimate hazard.

-John


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## Loose Neutral (Jun 3, 2009)

I got my a$$ lit up by 120. Thank god i was cutting the wire and not stripping it cause it caused me to get hung up. That's what gets you. I've been shocked on the side of the hand or finger and you can just pull away, but if it gets you wrong and causes you to grip it, watch out. I know after that I respect it more.


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## B4T (Feb 10, 2009)

How come Cletis didn't ask this question.. :blink::blink:


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## Subzer0IsGG (Sep 14, 2012)

Loose Neutral said:


> I got my a$$ lit up by 120. Thank god i was cutting the wire and not stripping it cause it caused me to get hung up. That's what gets you. I've been shocked on the side of the hand or finger and you can just pull away, but if it gets you wrong and causes you to grip it, watch out. I know after that I respect it more.


Caught up on 120...I just find that hard to believe, that doesn't tend to happen in 120
You must of cut the hot and common at the same time which made a short?
If you had boots on and cut one wire you would have no problem


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## JRaef (Mar 23, 2009)

It's a well established fact that when you are killed by 480V, you are far more dead than if you are killed by 120V. So 480V death is therefor worse than 120V death, making 120V less objectionale.

:thumbup:


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## BBQ (Nov 16, 2010)

Lots of good info in this pdf http://www.cdc.gov/niosh/docs/98-131/pdfs/98-131.pdf

This is kind of interesting.


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## 3xdad (Jan 25, 2011)

Second chart IS interesting. Sheesh, laborers need a pay raise.


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## Barjack (Mar 28, 2010)

Subzer0IsGG said:


> Caught up on 120...I just find that hard to believe, that doesn't tend to happen in 120
> You must of cut the hot and common at the same time which made a short?
> If you had boots on and cut one wire you would have no problem


I had boots on and was cutting one wire at a time.

I just forgot I was on an aluminum ladder in the dirt outside. I was hung up so bad I had to jump off the ladder to free myself. 

It was a 120V 15a circuit. 

I know, I know, dumb shiz thing to do. I couldn't tell you now why I was on an aluminum ladder.


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## RIVETER (Sep 26, 2009)

Going_Commando said:


> Before I have a cup of coffee every morning, I slap 120v across my nipples. Beats the hell out of caffeine!
> 
> 
> 
> ...


I thought I was the only one who did that. However, now I have to use a "D" cup.


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## Tsmil (Jul 17, 2011)

Barjack said:


> I had boots on and was cutting one wire at a time.
> 
> I just forgot I was on an aluminum ladder in the dirt outside. I was hung up so bad I had to jump off the ladder to free myself.
> 
> ...


120 definately hurts. I got bit once and now treat it with a great deal more respect than I did before. I was on a 10 ft fiberglass ladder leaning across a 2 x 4 light fixture reaching into a junction box I thought I had the circuit off but not. Grabbed my strippers and clamped on to the wire and it grabbed me. I couldn't let go and just hung there screaming until one of my coworkers kicked the ladder out from under me allowing me to fall free. I got the jolt from my hands to where my arms were resting on the light fixture. I walked away but treat 120 with a great deal more care now.


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## mikeyrob (Mar 16, 2012)

if 120 grabs you you need some thicker calluses on those hands.


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## dmxtothemax (Jun 15, 2010)

Subzer0IsGG said:


> Discuss.
> I already know its the ma that kills, and factors like compromised natural resistance will increase the ma. But lets be honest, how dangerous is it really...


Its more than enough to kill you !
How much more deadly does it have to be ?
You can't be deader than dead.

Or are you getting at something else ?
What ???


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## Elec-Tech (Oct 10, 2009)

Subzer0IsGG said:


> Caught up on 120...I just find that hard to believe, that doesn't tend to happen in 120
> You must of cut the hot and common at the same time which made a short?
> If you had boots on and cut one wire you would have no problem


With the right situation you sure as hell can get hung up. I think that the folks that are dying from it are getting hung up to some extent.


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## Elec-Tech (Oct 10, 2009)

Subzer0IsGG said:


> Caught up on 120...I just find that hard to believe, that doesn't tend to happen in 120
> You must of cut the hot and common at the same time which made a short?
> If you had boots on and cut one wire you would have no problem


what are you using?? Bare handled pliers??


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## greenman (Apr 20, 2012)

PAGE 8
http://www.osha.gov/dte/outreach/construction/focus_four/electrocution/electr_ig.pdf


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## runruh (Sep 19, 2012)

RGH said:


> ..how much is enough???...7 to 10 milli ampes will stop your heart....thats thousands of 1 amp.... .007 amps ...your instructors should cover this stuff in school....one of the reasons your choice of foot wear is very important in this trade...


I have never been shocked in the foot but I have been shocked through a knee on concrete when contacting what I call 110.


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## greenman (Apr 20, 2012)

They should stop doing our work!!!


3xdad said:


> second chart is interesting. Sheesh, laborers need a pay raise.


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## knowshorts (Jan 9, 2009)

My worst hit was from 120. Right hand was cinching up a zip tie at the bottom of a panel. Left hand was resting on the left edge of the panel, thankfully with my fingers pointing outward. As I cinched the zip tie it broke sending the back of my right hand into the bus. I only had one scratch from the bus, so I am assuming I only got hit by 120 and not 208. I normally have about a 3.38" vertical lift. I felt 4 cycles go through my body and was thrown about 4 feet away into a fence. 

I got distracted by the guy talking to me and got comfortable.


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## user4818 (Jan 15, 2009)

It's a shame that with all the safety regulations that lineman follow, that their fatality rate is still that high.  It also ought to shut up all the electricians who always say that since linemen work live all the time, it ought to be safe for us too.


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## Jlarson (Jun 28, 2009)

Peter D said:


> It's a shame that with all the safety regulations that lineman follow, that their fatality rate is still that high.  It also ought to shut up all the electricians who always say that since linemen work live all the time, it ought to be safe for us too.


I'd imagine that the number of lineman killed by voltages under 600 has gone down since 94. More stringent saftey requirements for them when working on low voltage.


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## greenman (Apr 20, 2012)

if you have bad work habbits on 120v, you will have bad work habbit on other voltages,
and what type of example is this for others.
all the contractors that i have worked for have a do not work live pollicy.
how do you know if the last guy did the job right?
“the nutrual on a three phase system”? 
up here is canada it is the law. YOU CAN NOT WORK LIVE.


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## sparky970 (Mar 19, 2008)

Tsmil said:


> Statistics like that mean nothing. Of coarse more people die from 120 than anything else. I haven't seen many ( or any) homes wired with 480 or 600.



That's why it's so dangerous, because it's
evrywhere


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## user4818 (Jan 15, 2009)

Jlarson said:


> I'd imagine that the number of lineman killed by voltages under 600 has gone down since 94. More stringent saftey requirements for them when working on low voltage.


True, I should have noticed that it was from '94.


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## chicken steve (Mar 22, 2011)

BBQ said:


> Lots of good info in this pdf http://www.cdc.gov/niosh/docs/98-131/pdfs/98-131.pdf
> 
> This is kind of interesting.


 
Good shootin' BBQ

what i am amazed at the most is the numero uno linesmans stats, because a large reason for the creation of the IBEW back in the guilded age was due to mortaility / morbidity stats

regardless of this history, they still seem to be leading the pack.......~CS~


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## wcord (Jan 23, 2011)

Subzer0IsGG said:


> Caught up on 120...I just find that hard to believe, that doesn't tend to happen in 120
> You must of cut the hot and common at the same time which made a short?
> If you had boots on and cut one wire you would have no problem


There are grabbers and throwers when it comes to getting shocked. 
Buddy of mine had a piece of AC90 short to his arm. His hand grabbed the jacket, so the current went from his arm to his hand. And he couldn't let go.
Left a hole that took over a year to heal.

As stated before, 120 kills if it goes thru you the right way.
Personally I've been bit by 347 twice and 600 3x now. Horseshoes that in all cases the path wasn't thru the heart.


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## 99cents (Aug 20, 2012)

Subzer0IsGG said:


> Discuss.
> I already know its the ma that kills, and factors like compromised natural resistance will increase the ma. But lets be honest, how dangerous is it really...


Were you asleep during your first year school? Dead is dead. If you ask "How deadly?", you already know the answer.

I sentence you to an industrial cable pull over the winter far away from anything energized.


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## don_resqcapt19 (Jul 18, 2010)

JRaef said:


> It's a well established fact that when you are killed by 480V, you are far more dead than if you are killed by 120V. So 480V death is therefor worse than 120V death, making 120V less objectionale.
> 
> :thumbup:


Actually a 480 volt shock is more likely to completely stop your heart and a 120 one is more likely to put you into ventricular fibrillation. CPR is more effective on a stopped heart than on one in fibrillation. However the 480 will likely cause a lot more burn damage.


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## Bulldog1 (Oct 21, 2011)

The only time I have ever got shocked really bad and almost pissed in my pants was 120V. I picked up a piece of MC cable to strip the aluminum off and check to see if it was hot. As soon as I picked it up it grabbed ahold of me and would not let me let go of it.  It felt like hours before I stepped on the cable and pulled it out of my hand. The customer was standing in front of me.....:laughing:


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## Jlarson (Jun 28, 2009)

Peter D said:


> True, I should have noticed that it was from '94.


Although I still see a few small/rural POCO guys hot dogging low voltage stuff.


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## dmxtothemax (Jun 15, 2010)

Elec-Tech said:


> With the right situation you sure as hell can get hung up. I think that the folks that are dying from it are getting hung up to some extent.


It's true that the current must follow a path,
But remember even with boots on and even one hand in your pocket,
The small amount of current flowing due to capacitive coupling,
This would still be enough to paralise your heart muscles.
Remember it only takes 50Ma or so to stop your heart.


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## ohmontherange (May 7, 2008)

Subzer0IsGG said:


> Discuss.
> I already know its the ma that kills, and factors like compromised natural resistance will increase the ma. But lets be honest, how dangerous is it really...


I think you really answered your own question. Under certain conditions it can be... well, deadly.


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## Going_Commando (Oct 1, 2011)

So, let's do some quick math. I just spent 2 hours on the 405 getting back from visiting my brother, and am sweaty. So, I am busting out my trusty Fluke 179, and will take some resistance measurements on my body, and then do the math later.

Place on Body Resistance 
Hand to hand: 450,000 ohms
Right thumb to right big toe: 400,000 ohms
Right thumb to tongue: 500,000 ohms
Nipple to nipple: 2,000 ohms
Right elbow to right thumb: 700,000 ohms
Forehead to right thumb: 625,000 ohms

So, even with the lowest resistance reading, from nipple to nipple @ 2000 ohms, the current going through my body is .06A @ 120v (60mA). Thus, I would have to become part of the circuit with other loads on it, to get to where the current is high enough to actually stop my heart, near as I can figure, and I would have to do that with my nipples. I used the current listings from this pdf to figure that out:
http://www.osha.gov/dte/outreach/construction/focus_four/electrocution/electr_ig.pdf


Still working on it, the reply went through before I was ready.


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## freeagnt54 (Aug 6, 2008)

I know a guy that got caught on 120v. He was on a demo job working above the grid, taking out some mc after making sure it was dead with his meter. It grabbed him for a few seconds and he somehow managed to kick the ladder out from under him bring the grid down with him. It turned out that the neither the neutral or ground were hooked up in the panel and the black was landed on a breaker. He was on a fiberglass ladder but he was leaning against the grid.


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## Subzer0IsGG (Sep 14, 2012)

dmxtothemax said:


> It's true that the current must follow a path,
> But remember even with boots on and even one hand in your pocket,
> The small amount of current flowing due to capacitive coupling,
> This would still be enough to paralise your heart muscles.
> Remember it only takes 50Ma or so to stop your heart.


Takes 10-20ma for ventricular fibrillation actually. 
Average human skin is 100, 000 ohms? 120/100, 000 = 1.2ma. Enough to make you numb at point of contact. When your sweaty or wet human resistance can go as low as 1000 omh. Which = 30ma enough to surely kill from 120.

I have nice dry working hand tough hands man hand. I touched either side of a plug when working live to straighten a plug from a reno and my fingers just went numb. No biggie. This why I find it hard people saying there getting hung up..


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## Subzer0IsGG (Sep 14, 2012)

Going_Commando said:


> So, let's do some quick math. I just spent 2 hours on the 405 getting back from visiting my brother, and am sweaty. So, I am busting out my trusty Fluke 179, and will take some resistance measurements on my body, and then do the math later.
> 
> Place on Body Resistance
> Hand to hand: 450,000 ohms
> ...


LOL zap your nipples please lmk know how that goes


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## kennydmeek (Sep 12, 2009)

Notice he didn't figure his lower appendage into the study...:whistling2:


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## Going_Commando (Oct 1, 2011)

kennydmeek said:


> Notice he didn't figure his lower appendage into the study...:whistling2:


I can do that if you want. :laughing:


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## Mulder (Sep 11, 2010)

wcord said:


> There are grabbers and throwers when it comes to getting shocked.
> Buddy of mine had a piece of AC90 short to his arm. His hand grabbed the jacket, so the current went from his arm to his hand. And he couldn't let go.
> Left a hole that took over a year to heal.
> 
> ...




F**k that s**t. You must have a death wish. Once was all it took for me. I want to see my kids grow up.


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## erics37 (May 7, 2009)

3xdad said:


> Second chart IS interesting. Sheesh, laborers need a pay raise.


They're expendable.


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## etb (Sep 8, 2010)

Subzer0IsGG said:


> Takes 10-20ma for ventricular fibrillation actually.
> Average human skin is 100, 000 ohms? 120/100, 000 = 1.2ma. Enough to make you numb at point of contact. When your sweaty or wet human resistance can go as low as 1000 omh. Which = 30ma enough to surely kill from 120.
> 
> I have nice dry working hand tough hands man hand. I touched either side of a plug when working live to straighten a plug from a reno and my fingers just went numb. No biggie. This why I find it hard people saying there getting hung up..



So because you grabbed a rcpt and had some tingly fingers, you can't believe people get caught on 120, even though there's plenty of people here that say they've been hung up? I guess if you want to keep grabbing hot rcpts, go ahead.

On a remodel that another electrician had started but abandoned, I wiggy'd a rcpt hanging out of the box that had paint overspray on the screws; should have known better and probed the front. So I grabbed it to unwire it but the screw was real tight so I grabbed harder and it latched me on. Felt like my forearm was on steroids. It locked up my whole arm and shoulder and I had to lunge backward to get off. I was on my knees so even that was hard to do. Thankfully everything was alright but I couldn't operate my hand for several minutes afterward and it was so sore I couldn't work for days.


Also, your resistance calculations that say only 1.2mA can flow are worthless. Skin is a nonlinear resistor; it doesn't follow ohm's law. After current starts to flow the resistance decreases, which allows more current, and that's still with skin left. If it gets to the level that the skin burns away, you're then talking in the hundreds of ohms.


I was in an attic and opened a neutral on a dead circuit but somebody stole that neutral upstream. Rafters were so dry that it was just a slight buzz and I was lucky. On the other hand, I've read countless accident investigations were eyewitnesses saw the electrocution on the spot at only 120V, and others were the bystander was only gone for a few minutes and they come back and the guy's dead, probably latched on.


The facts are that some circumstances, you can get hit with 120 and walk away. Other times, that's it. How a person wants to handle that risk is up do them.


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## brian john (Mar 11, 2007)

Subzer0IsGG said:


> Discuss.
> I already know its the ma that kills, and factors like compromised natural resistance will increase the ma. But lets be honest, how dangerous is it really...


Well it can be permanent (as in pushing up daisy's)


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## user8640521 (Jan 17, 2009)

Subzer0IsGG said:


> Caught up on 120...I just find that hard to believe,
> that doesn't tend to happen in 120


really?

my BS filter is now completely clogged.

the closest i've ever come to dying was on a 120 volt
circuit supplying 6 can lights.

i went arm to arm, supplying the remaining 15 amps
necessary to trip the breaker.

i didn't short the circuit to ground, it went in my left hand
between two fingers, and exited the heel of my right hand,
across the chest. i was wearing a long sleeve sweater, so
the current path was pretty well constrained.

knocked me out, sitting on top of a ladder, in a 2X2 t-bar
ceiling. the grid kept me from falling off the ladder.

i don't remember it at all. the receptionist in the office
said she could hear me screaming.

black and purple palms. no charring of the skin.

i'm going to hope fervently that you never get to experience
first hand just how full of chit your beliefs are.


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## BBQ (Nov 16, 2010)

Going_Commando said:


> So, even with the lowest resistance reading, from nipple to nipple @ 2000 ohms, the current going through my body is .06A @ 120v (60mA). *Thus, I would have to become part of the circuit with other loads on it, to get to where the current is high enough to actually stop my heart, *


You need to think on that part some more, putting your body in series with any load will only reduce the current going through you.

And 60 mA _'nip to nip'_ has a high likelihood of disturbing your heart beat if not stop it.


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## chewy (May 9, 2010)

I worked with a sparky who didn't think he "conducted", I saw him get shocked several times and the most I ever heard was a Fonzie like "eeeh". One time he was working behind me and I saw what I first thought were camera flashes, I turned around and electricity was arcing out of a JB onto his bald head and he didn't even notice until I yelled out to him and he just looked around saying "What?, What?" as he moved the arc kept following him.

Biggest arc I have seen was when I lent out my Hitachi with no safety clutch to a guy that was a labrador for us to drill some drops, the auger bound up and ate up the cord somehow jamming his finger on the trigger and against a stud with the drill on full power pinning him to the framing, I ran over and pulled the leads apart and they arced a good meter apart.


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## denny3992 (Jul 12, 2010)

knowshorts said:


> My worst hit was from 120. Right hand was cinching up a zip tie at the bottom of a panel. Left hand was resting on the left edge of the panel, thankfully with my fingers pointing outward. As I cinched the zip tie it broke sending the back of my right hand into the bus. I only had one scratch from the bus, so I am assuming I only got hit by 120 and not 208. I normally have about a 3.38" vertical lift. I felt 4 cycles go through my body and was thrown about 4 feet away into a fence.
> 
> I got distracted by the guy talking to me and got comfortable.


Theres ur mistake, my 1st elec instructor taught us to work with one hand on ur ass. So u cant get it across the chest!


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## chewy (May 9, 2010)

denny3992 said:


> Theres ur mistake, my 1st elec instructor taught us to work with one hand on ur ass. So u cant get it across the chest!


Did he demonstrate with you in private?


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## wildleg (Apr 12, 2009)

denny3992 said:


> Theres ur mistake, my 1st elec instructor taught us to work with one hand on ur ass. So u cant get it across the chest!


if you wind up coming to an ET meetngreet, remind me not to shake your hand


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## denny3992 (Jul 12, 2010)

chewy said:


> Did he demonstrate with you in private?


That was a quick path to the gutter chewy!


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## denny3992 (Jul 12, 2010)

wildleg said:


> if you wind up coming to an ET meetngreet, remind me not to shake your hand


Every good electrician wears gloves, right?


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## local134gt (Dec 24, 2008)

knowshorts said:


> I felt 4 cycles go through my body


:blink:


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## chewy (May 9, 2010)

denny3992 said:


> That was a quick path to the gutter chewy!


Im already there, its easy to drag stuff down : p


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## Chris1980 (Sep 18, 2012)

More people die from 120v because it's what voltage is in the house.homeowners do there own work and don't know what there doing resulting in more deaths.


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## BBQ (Nov 16, 2010)

Chris1980 said:


> More people die from 120v because it's what voltage is in the house.homeowners do there own work and don't know what there doing resulting in more deaths.


To take it further, it is everywhere, not just the home but everywhere in the workplace as well.

But the point is it still certainly kills.


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## knowshorts (Jan 9, 2009)

denny3992 said:


> Theres ur mistake, my 1st elec instructor taught us to work with one hand on ur ass. So u cant get it across the chest!


I made all kinds of mistakes that day. I was fortunate it only cost me a $1000 at the ER to check my heart rather than a few thousand to bury my ass.

I was using ty wraps that had been stored in the back of my truck for a few months.
I allowed someone to distract me while I was working in a panel.
I allowed my left hand to be grounded.
I was not wearing my gloves.
And the main mistake I made was getting comfortable around 120 thinking it was "safe" and not respecting it like I was taught.


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## Chris1980 (Sep 18, 2012)

Usually the workplace hires contractors where homeowners assume replacing a simple snap switch or light fixture is an easy task.


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## jimmy21 (Mar 31, 2012)

How many people get killed by 120v where water isn't involved?



I hate when homeowners say something like. I got shocked by 120v but it was on 100amp breaker. One guy I know, told me a story about doing **** he shouldn't have been doing, at the bar he was working at. He said he was pulling some mc cable and the end whipped up and into the panel. He said it hit one of the 120v busses and the side of the can causing an arc. He said he was holding the other end of the mc cable 30 feet away and he was thrown from his fiberglass ladder (where he was completely ungrounded) and knocked unconscious and was partially paralyzed for the rest of the day. All because he got shocked by 200 amps.


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## Chris1980 (Sep 18, 2012)

Ok first of all you can't get shocked from 200 amps or 100 amps unless the the service is pulling that kind of amperage at that time.120/240 is what shocks you and whatever amperage is on that circuit . Hopefully you can be around to tell the story.point is you need to be careful working on any electrical and have an understanding on how it works.i recommend a arc flash nfpa 70 class and an OSHA 10 or 30 class.


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## don_resqcapt19 (Jul 18, 2010)

Chris1980 said:


> Ok first of all you can't get shocked from 200 amps or 100 amps unless the the service is pulling that kind of amperage at that time.120/240 is what shocks you and whatever amperage is on that circuit . Hopefully you can be around to tell the story.point is you need to be careful working on any electrical and have an understanding on how it works.i recommend a arc flash nfpa 70 class and an OSHA 10 or 30 class.


The current on the service has nothing to do with the current through your body when you get a shock. The current through your body is based on the voltage and the impedance of the path though your body. Given the same voltage and body conditions, the current through the person is the same on a service with 10 amps of load as it would be on a service with 10,000 amps of load.


----------



## BBQ (Nov 16, 2010)

Chris1980 said:


> Usually the workplace hires contractors where homeowners assume replacing a simple snap switch or light fixture is an easy task.


Chris, look at the graphs I posted and the number of labors killed. That is in the workplace.


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## Legacyelectric (Sep 9, 2012)

Electric fences are great teaching tools for demonstrating how this all works. Touch it with your hand.... Now take your shoes off and pee on it.... Fence didn't change, voltage didn't change, size of service ( mile charging rating) didn't change. Now you understand.


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## chewy (May 9, 2010)

Legacyelectric said:


> Electric fences are great teaching tools for demonstrating how this all works. Touch it with your hand.... Now take your shoes off and pee on it.... Fence didn't change, voltage didn't change, size of service ( mile charging rating) didn't change. Now you understand.


If that effects the feeling of the shock, wouldnt I be immune to the shock from an electric fence in rubber boots?


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## Chris1980 (Sep 18, 2012)

My point is that electrical safety is so important whetever you are. And it can't be taken likely.


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## Legacyelectric (Sep 9, 2012)

chewy said:


> If that effects the feeling of the shock, wouldnt I be immune to the shock from an electric fence in rubber boots?


I've never intentionally touched one with rubber boots on to find out, I can assure you though that a regular old pair of Georgia boots does NOT insulate you from ground enough to prevent current flow. 

And it would definitely effect the amount of current flow if the resistance was decreased ie barefooted and mineral/salt laden urine with a path directly to your insides. Increase current by decreasing resistance with a given voltage, would be huge difference in the "shock value" ! I've never tested this. Just a theory.


----------



## Chris1980 (Sep 18, 2012)

Electricity finds the path of least resistance so how it finds it's way to ground(earth)you never know how bad it's gonna be. An electric fence is dc and last time I checked it felt worse than ac.


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## chewy (May 9, 2010)

Legacyelectric said:


> I've never intentionally touched one with rubber boots on to find out, I can assure you though that a regular old pair of Georgia boots does NOT insulate you from ground enough to prevent current flow.
> 
> And it would definitely effect the amount of current flow if the resistance was decreased ie barefooted and mineral/salt laden urine with a path directly to your insides. Increase current by decreasing resistance with a given voltage, would be huge difference in the "shock value" ! I've never tested this. Just a theory.


Having grown up on farms wearing "gumboots" which are vulcanised rubber galoshes or wellingtons I got plenty of shocks, just wondering if there was another factor involved if I "shouldnt" have been getting shocked.


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## chewy (May 9, 2010)

Chris1980 said:


> Electricity finds the path of least resistance so how it finds it's way to ground(earth)you never know how bad it's gonna be. An electric fence is dc and last time I checked it felt worse than ac.


Worst one I had, I slipped into a pond and grabbed the fence (fenced off to keep cattle out of the waterways), my hand ached all day.


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## Legacyelectric (Sep 9, 2012)

chewy said:


> If that effects the feeling of the shock, wouldnt I be immune to the shock from an electric fence in rubber boots?


That's even better if you are immune with rubber boots! Now take them off and touch it.... Just seems like a good, easy to remember, less than lethal hands on demo of the relationship between body resistance, grounding, and source voltage/current rating irrelevance (to a certain extent).


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## chewy (May 9, 2010)

Legacyelectric said:


> That's even better if you are immune with rubber boots! Now take them off and touch it.... Just seems like a good, easy to remember, less than lethal hands on demo of the relationship between body resistance, grounding, and source voltage/current rating irrelevance (to a certain extent).


No your not immune, dont try it on the bull fence! :laughing:


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## etb (Sep 8, 2010)

chewy said:


> If that effects the feeling of the shock, wouldnt I be immune to the shock from an electric fence in rubber boots?


An electric fence is a bit different, as it's a pulse. A capacitor can pass a pulse; the pulse is similar to high-frequency current in that regard. So you'll likely still get hit by the fence if wearing rubber boots on a big fencer; smaller ones maybe not. You, your boots, and the earth make a capacitor. When I was a kid, I learned that the hard way.


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## chewy (May 9, 2010)

etb said:


> An electric fence is a bit different, as it's a pulse. A capacitor can pass a pulse; the pulse is similar to high-frequency current in that regard. So you'll likely still get hit by the fence if wearing rubber boots on a big fencer; smaller ones maybe not. You, your boots, and the earth make a capacitor. When I was a kid, I learned that the hard way.


Yeah you can hear it clicking when its hitting a bit of long grass in the morning after a dew.


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## Legacyelectric (Sep 9, 2012)

Chris1980 said:


> Electricity finds the path of least resistance so how it finds it's way to ground(earth)you never know how bad it's gonna be. An electric fence is dc and last time I checked it felt worse than ac.


Ohms law works for DC and AC. DC might feel worse , but I'm trying to set up a relative experiment. Not relative to AC 120v, but when you had shoes on relative to when you did not.


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## electrictim510 (Sep 9, 2008)

The attitude I see about 120v on this forum is exactly why so many people die from it. 
The whole argument of 'you can't get hung up on 120v' suprises me coming from fellow electricians. A friend of mine (apprentice acting like he was a journeyman :whistling2 was nearly killed getting hung up on 120v working in t-bar ceiling. 

Thinking about it; even when you get hit working on more than 120v, odds are when you get electrocuted it is only 120v. Unless you get between more than one leg or a high leg. 

Just because you personally have never experienced it does not mean it does not happen. As electricians we tend to steer clear of situations a little better than most so that we do not end up in situations that may hang us up on any voltage (hence the low numbers of electricians getting killed even though we are the ones who work with it most.)

This topic is the reason I never trust anyone when working live. "I turned the breaker off" Really? Ok, well I will double check that, thank you. If you don't respect electricity as much as I do I would prefer not to work around you.


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## Legacyelectric (Sep 9, 2012)

chewy said:


> Yeah you can hear it clicking when its hitting a bit of long grass in the morning after a dew.


It's animal cruelty is what it is.


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## etb (Sep 8, 2010)

Legacyelectric said:


> Ohms law works for DC and AC. DC might feel worse , but I'm trying to set up a relative experiment. Not relative to AC 120v, but when you had shoes on relative to when you did not.


A fence is dc alright, but it's a pulse so you can't do much with ohm's law. Fencers are designed to output a fixed amount of energy, like 5 mJ, to limit how far up your arm the pulse goes. Long ago fencers weren't pulse design, they were continuous and people and livestock died as a result; they also caused fires when they heated up weeds across the fence.


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## chewy (May 9, 2010)

Legacyelectric said:


> It's animal cruelty is what it is.


One zap and they generally dont go near it again.


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## Chris1980 (Sep 18, 2012)

Rule number 1 is never trust anyone when it comes to electricity. I tell all my guys that. You lock out and tag out something you take it off.


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## ibuzzard (Dec 28, 2008)

Not sure if it's true,but I was told that there are more electrocutions in the US from 120 volts, than from all other voltages combined.You see, apparently some (few?) less than clear-thinking individuals are under the mistaken impression that it's safe.Good candidates for the Darwin awards.


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## John Valdes (May 17, 2007)

I cut through a piece of NM a few weeks ago while installing a dusk to dawn porch light here at home. 120 volts. Thought the breaker was off. I had cut the end of the NM flush/square after the wire was installed and folded it neatly in the box. I guess I turned it back on for the receptacles and did not think. 
When I went to make a fresh the cut the next day, it blew. Made a nice hole in my strippers.
It really made me think. I used to do this work every day and really never gave it a whole lot of thought. I don't care what the voltage is. Turn off the breaker. And make sure you check the breaker again before resuming work.


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## electrictim510 (Sep 9, 2008)

I even disconnect wires from the breakers whenever it is realistic.


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## don_resqcapt19 (Jul 18, 2010)

Chris1980 said:


> Electricity finds the path of least resistance so how it finds it's way to ground(earth)you never know how bad it's gonna be. An electric fence is dc and last time I checked it felt worse than ac.


Electricity takes all available paths back to the source. It does not try to go to "ground", but the ground may be one available path back to the source.


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## guest (Feb 21, 2009)

Chris1980 said:


> Ok first of all you can't get shocked from 200 amps or 100 amps _*unless the the service is pulling that kind of amperage at that time.*_120/240 is what shocks you _*and whatever amperage is on that circuit .*_ Hopefully you can be around to tell the story.point is you need to be careful working on any electrical and have an understanding on how it works.i recommend a arc flash nfpa 70 class and an OSHA 10 or 30 class.


Wrong, wrong, wrong!! EDIT: (As Don resqcapt19 pointed out in post #74, which I didn't catch till after I posted this.) 

It is the current flow _*through your body that matters*_, as governed by Ohm's Law, NOT what the service happens to be "pulling at that time". 

If you body creates a low enough resistance path to ground (or neutral, or to the other phase) to allow a high(er) current flow that's what you'll get hit with. (Up to the limits of the service conductors and feed transformer.) 

Think of your body as a simple resistor in the circuit and do the math and you'll see how it really works out. (And yes, in reality the body has capacitance as well as resistance but let's keep to the basics.) 

I find disturbing the number of electricians who have that same misconception.


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## chicken steve (Mar 22, 2011)

etb said:


> A fence is dc alright, but it's a pulse so you can't do much with ohm's law. Fencers are designed to output a fixed amount of energy, like 5 mJ, to limit how far up your arm the pulse goes. Long ago fencers weren't pulse design, they were continuous and people and livestock died as a result; they also caused fires when they heated up weeds across the fence.


Once when i tied on on, i held the fence and placed a pointed finger on all my buds around me

kinda felt like Zeus!

~CS~


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## guest (Feb 21, 2009)

chicken steve said:


> Once when i tied on on, i held the fence and placed a pointed finger on all my buds around me
> 
> kinda felt like _*a douche*_!
> 
> ~CS~



Fixed it for you. :thumbsup::laughing::laughing:


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## Rockyd (Apr 22, 2007)

don_resqcapt19 said:


> Electricity takes all available paths back to the source. It does not try to go to "ground", but the ground may be one available path back to the source.


Thanks for reiterating that electricity tries to take ALL paths home.....Bad electrons do not get pumped into the earth! Oh some may, but they are just trying to make their way back to the source - make sure you're not one of the paths!

I have a crew of five to ten guys, and we never buy into someone else saying "I turned the breaker off". Lock out Tag out, and a personal lock are your best friends. Beyond that, I ask that everyone always test the thing your about to work on before touching it.


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## Big John (May 23, 2010)

Subzer0IsGG said:


> Caught up on 120...I just find that hard to believe...


 Believe it. Worst shock of my life was getting hit by 120V while sweaty and it absolutely locked me up.

-John


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## erics37 (May 7, 2009)

Big John said:


> Believe it. Worst shock of my life was getting hit by 120V while sweaty and it absolutely locked me up.
> 
> -John


Another initiation rite I had to perform to be admitted to the IBEW was to cut open the palm of my hand with a shard of broken glass and insert a bare copper wire directly into my bloodstream and energize it with 277. That was a few weeks after I had to curb stomp a non-union guy.


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## BBQ (Nov 16, 2010)

erics37 said:


> Another initiation rite I had to perform to be admitted to the IBEW was to cut open the palm of my hand with a shard of broken glass and insert a bare copper wire directly into my bloodstream and energize it with 277. That was a few weeks after I had to curb stomp a non-union guy.



I think they were just trying to keep you out .......... just saying.


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## erics37 (May 7, 2009)

BBQ said:


> I think they were just trying to keep you out .......... just saying.


Well I played their little game and I emerged victorious! My plan for world domination is one step closer to fruition!


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## Chris1980 (Sep 18, 2012)

Electric shock occurs upon contact of a (human) body part with any source of electricity that causes a sufficient current through the skin, muscles, or hair. Typically, the expression is used to describe an injurious exposure to electricity.[1]

The minimum current a human can feel depends on the current type (AC or DC) and frequency. A person can feel at least 1 mA (rms) of AC at 60 Hz, while at least 5 mA for DC. The current may, if it is high enough, cause tissue damage or fibrillation which leads to cardiac arrest. 60 mA of AC (rms, 60 Hz) or 300–500 mA of DC can cause fibrillation.[2][3] A sustained electric shock from AC at 120 V, 60 Hz is an especially dangerous source of ventricular fibrillation because it usually exceeds the let-go threshold, while not delivering enough initial energy to propel the person away from the source. However, the potential seriousness of the shock depends on paths through the body that the currents take.[2] Death caused by an electric shock is called electrocution.

If the voltage is less than 200 V, then the human skin, more precisely the stratum corneum, is the main contributor to the impedance of the body in the case of a macroshock—the passing of current between two contact points on the skin. The characteristics of the skin are non-linear however. If the voltage is above 450–600 V, then dielectric breakdown of the skin occurs.[4] The protection offered by the skin is lowered by perspiration, and this is accelerated if electricity causes muscles to contract above the let-go threshold for a sustained period of time.[2]

If an electrical circuit is established by electrodes introduced in the body, bypassing the skin, then the potential for lethality is much higher if a circuit through the heart is established. This is known as a microshock. Currents of only 10 µA can be sufficient to cause fibrillation in this case.[citation needed] This is a concern in modern hospital settings when the patient is connected to multiple devices.

HideSigns and symptoms


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## erics37 (May 7, 2009)

Chris1980 said:


> ....


WTF is with all the people with names substantially similar to existing user names lately?

EricS37 - EricS
Peter D - Peter11
Chris1971 - Chris1980

I'm waiting to seeing Slow Petey, 479Sparky, Brian's John, etc.


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## Chris1980 (Sep 18, 2012)

Who cares what your screen name is?


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## erics37 (May 7, 2009)

Chris1980 said:


> Who cares what your screen name is?


Mitt Romney cares!


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## Chris1980 (Sep 18, 2012)

erics37 said:


> Mitt Romney cares!


I am gonna keep my mouth shut cause this is not a political discussion


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## erics37 (May 7, 2009)

Chris1980 said:


> I am gonna keep my mouth shut cause this is not a political discussion


It is now :brows: :shifty:


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## ibuzzard (Dec 28, 2008)

Chris1980 said:


> I am gonna keep my mouth shut cause this is not a political discussion


Excellent idea!For ANY discussion!


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## eejack (Jul 14, 2012)

erics37 said:


> Another initiation rite I had to perform to be admitted to the IBEW was to cut open the palm of my hand with a shard of broken glass and insert a bare copper wire directly into my bloodstream and energize it with 277. That was a few weeks after I had to curb stomp a non-union guy.


Ah the good old days.


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## Chris1980 (Sep 18, 2012)

eejack said:


> Ah the good old days.


What local are you? I am 379 charlotte


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## eejack (Jul 14, 2012)

Chris1980 said:


> What local are you? I am 379 charlotte


Local #164 - Jersey City NJ. Welcome to the site.


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## Legacyelectric (Sep 9, 2012)

etb said:


> A fence is dc alright, but it's a pulse so you can't do much with ohm's law. Fencers are designed to output a fixed amount of energy, like 5 mJ, to limit how far up your arm the pulse goes. Long ago fencers weren't pulse design, they were continuous and people and livestock died as a result; they also caused fires when they heated up weeds across the fence.


I don't understand why you can't do much with ohms law in this instance. If the voltage at pulse is known, and resistance is known, shouldn't current flow behave like it always does? I don't know it all, if I'm wrong here tell me.


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## chicken steve (Mar 22, 2011)

erics37 said:


> WTF is with all the people with names substantially similar to existing user names lately?
> 
> EricS37 - EricS
> Peter D - Peter11
> ...


Hummingbird Steve......:blink:


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## chicken steve (Mar 22, 2011)

Worked for a dude named Morris, we all called him Moe

he used to 'test' voltage with his index and middle finger (think Spock), and inform the crew if it was 120 ,or something else

he also used to smoke filterless Camels, and often burnt the flesh on his fingers to the point where others would have to inform him of it

Moe's long gone, dust, died of alcoholism

But this was a part of my indoctrination, along with _*'backhanding'*_ (there's one for you trade duffers) , so it's mighty hard to take up 70E, and give it the attention it rightly deserves

~CS~


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## electrictim510 (Sep 9, 2008)

I do that test also as long as I have no meter to test if it's dead. Short path that doesnt go through the heart I fugure it is a little safer...


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## chicken steve (Mar 22, 2011)

Thus _'backhanding'_ Tim.....~CS~


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## Chris1980 (Sep 18, 2012)

electrictim510 said:


> I do that test also as long as I have no meter to test if it's dead. Short path that doesnt go through the heart I fugure it is a little safer...


I'm sorry but that's just stupid. I understand it was the old method but we have a better understanding now of electricity .


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## chicken steve (Mar 22, 2011)

So you've a preferred alternate body part '80?

~CS~


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## Aegis (Mar 18, 2011)

I have a problem with 'it's the amps that kill you', because it takes a certain amount of voltage to push those amps through you. Also the fatter you are the safer you are lol


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## Chris1980 (Sep 18, 2012)

chicken steve said:


> So you've a preferred alternate body part '80?
> 
> ~CS~


How about treat it like its live. Never assume.get a tick tracer and carry it around with you.


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## chicken steve (Mar 22, 2011)

Induction testers are the biggest_ liars_ Chris.....

sooner of later, ya gotta make _bodily_ contact......

any of you brave souls with a prehensile d*ck feel free to chime in....

~CS~


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## Chris1980 (Sep 18, 2012)

chicken steve said:


> Induction testers are the biggest liars Chris.....
> 
> sooner of later, ya gotta make bodily contact......
> 
> ...


Yeah you are right they will pick up like 3 volts.but you do what you want I am not gonna stop you. If your in that situation it will not matter if your comfortable working with electricity.


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## jimmy21 (Mar 31, 2012)

chicken steve said:


> Induction testers are the biggest_ liars_ Chris.....
> 
> sooner of later, ya gotta make _bodily_ contact......
> 
> ...


They lie and tell you something is live when it isn't. I don't think I've ever seen where one tells you its dead and it isn't. Unless I guess the thing is broken


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## chicken steve (Mar 22, 2011)

Chris1980 said:


> Yeah you are right they will pick up like 3 volts.but you do what you want I am not gonna stop you. If your in that situation it will not matter if your comfortable working with electricity.


good point

so what is _'comfortable'_ Chris?

one's fav tester? a note from the poco?

well sooner or later it's a matter of _trust_

myself, after any tester work, i'll touch a conductor to ground

last, i'll backhand it, just in case said ground isn't for real

so....what do you trust you well being to?

~CS~


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## BBQ (Nov 16, 2010)

I use my tick tracer and feel great about it.

Rub the tester on my arm to test it, check circuit, rub the tester on my arm again to check it again.


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## Chris1980 (Sep 18, 2012)

BBQ said:


> I use my tick tracer and feel great about it.
> 
> Rub the tester on my arm to test it, check circuit, rub the tester on my arm again to check it again.


Exactly


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## sarness (Sep 14, 2010)

Electric fences can shock you when your wearing rubber boots because your body is disipating the electricity into the air.

It's why birds don't get electrocuted sitting on high tension wires, their body mass is too small.


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## ohmontherange (May 7, 2008)

You guys are freaking nuts obsessing over this 5hit. Iv'e been hit by both 120V and 277V and didn't like either one. Kill the power, lock it out, test it, be safe.


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## chicken steve (Mar 22, 2011)

BBQ said:


> I use my tick tracer and feel great about it.
> 
> Rub the tester on my arm to test it, check circuit, rub the tester on my arm again to check it again.


 
Curiosity has the better of me BBQ....the theory being ?

~CS~


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## chicken steve (Mar 22, 2011)

sarness said:


> Electric fences can shock you when your wearing rubber boots because your body is disipating the electricity into the air.
> 
> It's why birds don't get electrocuted sitting on high tension wires, their body mass is too small.


a rather eloquent way of calling one_ fat_ Sarness....:jester:~CS~


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## Chris1980 (Sep 18, 2012)

ohmontherange said:


> You guys are freaking nuts obsessing over this 5hit. Iv'e been hit by both 120V and 277V and didn't like either one. Kill the power, lock it out, test it, be safe.


I've tried to say that a long time ago.thank you


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## BBQ (Nov 16, 2010)

chicken steve said:


> Curiosity has the better of me BBQ....the theory being ?
> 
> ~CS~


The theory being verify the tester works before and after, exactly like I do if I use a regular meter.


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## chicken steve (Mar 22, 2011)

BBQ said:


> The theory being verify the tester works before and after, exactly like I do if I use a regular meter.


understood, and it's exactly what most tester manufacturers _insist_ on

but it's the _rub on your arm_ part i'm fuzzy on

can U expand on this?

~CS~


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## erics37 (May 7, 2009)

chicken steve said:


> understood, and it's exactly what most tester manufacturers _insist_ on
> 
> but it's the _rub on your arm_ part i'm fuzzy on
> 
> ...


Get your tick tracer out and rub it vigorously on your arm, it'll light up and beep unless you're dead. Which segues into another useful feature; it's an excellent undead creature detection device.


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## Legacyelectric (Sep 9, 2012)

sarness said:


> Electric fences can shock you when your wearing rubber boots because your body is disipating the electricity into the air.
> 
> It's why birds don't get electrocuted sitting on high tension wires, their body mass is too small.


Huh?


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## Legacyelectric (Sep 9, 2012)

The only tick tracer I've found that is both reliable, and correct all the time is the fluke.


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## Legacyelectric (Sep 9, 2012)

Greenlee ones where you twist the end to turn it on/off are dangerous.


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## Chris1980 (Sep 18, 2012)

Legacyelectric said:


> Greenlee ones where you twist the end to turn it on/off are dangerous.


I agree


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## ohmontherange (May 7, 2008)

sarness said:


> Electric fences can shock you when your wearing rubber boots because your body is disipating the electricity into the air.
> 
> It's why birds don't get electrocuted sitting on high tension wires, their body mass is too small.


You are kidding aren't you?


----------



## John Valdes (May 17, 2007)

don_resqcapt19 said:


> Electricity takes all available paths back to the source. It does not try to go to "ground", but the ground may be one available path back to the source.


Good reminder.



Chris1980 said:


> Who cares what your screen name is?


Everyone on this forum



Chris1980 said:


> What local are you? I am 379 charlotte


Do you know a guy named William? We had a guy here called william1978 if I remember correctly. Union guy. Nice guy. I have wondered where he has gone.



chicken steve said:


> Worked for a dude named Morris, we all called him Moe
> he used to 'test' voltage with his index and middle finger (think Spock), and inform the crew if it was 120 ,or something else
> he also used to smoke filterless Camels, and often burnt the flesh on his fingers to the point where others would have to inform him of it
> Moe's long gone, dust, died of alcoholism
> ...


Steve it seems you and I come from the same mold. I also had teachers of this trade tell me to get used to electric shock as it was part of the job.
I have seen sparks in the name of electrical roundup. And chest beating as if they won the cup.
You sound just like Doc Holiday in the movie "Tombstone". If you ever catch that flick, you are a mirror image. In a good way.



ohmontherange said:


> You are kidding aren't you?


This thread reminds me of drunken apprentices after a meeting.


----------



## ohmontherange (May 7, 2008)

John Valdes said:


> Good reminder.
> 
> 
> 
> ...


Well said.


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## Subzer0IsGG (Sep 14, 2012)

sarness said:


> It's why birds don't get electrocuted sitting on high tension wires, their body mass is too small.



Uhh. No. 
Reason they don't get electrocuted is because both their feet stay on one phase. You should know there is no potential between two spots on the same phase.
Now if said bird had a large wingspan which touched surgery wire save time as he's on one. kungpow chicken


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## Subzer0IsGG (Sep 14, 2012)

Still can't find edit button in the app


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## freeagnt54 (Aug 6, 2008)

Legacyelectric said:


> The only tick tracer I've found that is both reliable, and correct all the time is the fluke.


Don't put so much trust in your no contact. I was working some 277 jboxes in a lift with another guy he checked it with his fluke nc and got nothing, and just as he was about to touch it I checked with my no contact (milwaukee) and it went off. I'm not saying anything brand is better than any others but regardless you can get a false negative. Like steve after testing with my no contact I slap it against the ground before I touch it with my hands.


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## Legacyelectric (Sep 9, 2012)

freeagnt54 said:


> Don't put so much trust in your no contact. I was working some 277 jboxes in a lift with another guy he checked it with his fluke nc and got nothing, and just as he was about to touch it I checked with my no contact (milwaukee) and it went off. I'm not saying anything brand is better than any others but regardless you can get a false negative. Like steve after testing with my no contact I slap it against the ground before I touch it with my hands.


I always double check. Ideal nc is not reliable, along with the greenlee. Fluke has been great.


----------



## etb (Sep 8, 2010)

Legacyelectric said:


> I don't understand why you can't do much with ohms law in this instance. If the voltage at pulse is known, and resistance is known, shouldn't current flow behave like it always does? I don't know it all, if I'm wrong here tell me.


The resistance in ohm's law only applies at DC. For AC you have to use impedance. That's not a problem at 60Hz but impedance changes with frequency. A circuit's response to a pulse is simliar to that circuit's response to a high frequency sinewave. The sharper the pulse, the higher the frequency of the corresponding sinewave. But although the response is "similar" you still can't use ohm's law (even using impedance) because that only applies to steady state (eg 60 Hz). So any circuit's response to DC is not the same as it's response to a pulse. Google RC filter for an idea.

If you have 50' of 1/4" rope tied on the end and laying straight on the ground and you quickly snap it, you'll watch the wave travel down the rope. Do that with a 3/4" rope and the wave will be smaller and not go as far. Do that with a 2" rope and you get the picture. Everything in nature is a low-pass filter, your body included; it acts as a capacitor that absorbs the charge. The thicker rope corresponds to a weaker or slower pulse zapping you.

The amount of energy stored in the discharge cap of the fencer determines the amplitude of the pulse, and the winding ratio and wire gauge on the impulse transformer determines how fast the pulse is. Faster pulses penetrate the skin less, slower pulses are more painful. The weaker fencers (1 mile) may only be 2mJ; the pulse might make it up your hand a way. The strongest fencer is probably a 20-mile; probably near 30mJ. That might make it most of the way up your arm, or further, depending on how long the actual fence is.



freeagnt54 said:


> Don't put so much trust in your no contact. I was working some 277 jboxes in a lift with another guy he checked it with his fluke nc and got nothing, and just as he was about to touch it I checked with my no contact (milwaukee) and it went off. I'm not saying anything brand is better than any others but regardless you can get a false negative. Like steve after testing with my no contact I slap it against the ground before I touch it with my hands.


I got nailed after my NCV said dead; turned out to be a cold solder joint on a POS fluke. Anymore, I just use NCV for troubleshooting. I don't touch until wiggy says dead, and then I quickly brush it or short to ground before I go to grabbing on it.


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## 220/221 (Sep 25, 2007)

Subzer0IsGG said:


> Discuss.
> How deadly is 120v.



It depends on if and how you touch it, right?

If you get hung up, it will of course cause your heart to squeeze tight and stop beating. That's never a good thing.

It can also knock you the **** off a ladder which can lead to all sorts of issues.

Usually it just makes you go "Gahhh!" It gave me a bloody nose one time when I jerked my hand away and popped myself in the nose.



> I have nice dry working hand tough hands man hand. I touched either side of a plug when working live to straighten a plug from a reno and my fingers just went numb. No biggie. This why I find it hard people saying there getting hung up..


Because you simply _touched _the 120V. You can safely touch the ends of a 120V cable with your finger tips and feel nothing. As you press a little harder, and begin to make better contact, you start to feel it slightly. If you get a good*grip* on a wire, all your muscles contract and you get hung up.


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## stuiec (Sep 25, 2010)

Working live = Playing with fire...and farts


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## sarness (Sep 14, 2010)

Subzer0IsGG said:


> Uhh. No.
> Reason they don't get electrocuted is because both their feet stay on one phase. You should know there is no potential between two spots on the same phase.
> Now if said bird had a large wingspan which touched surgery wire save time as he's on one. kungpow chicken


I'm usually only wrong once a year, and the year is almost over with, so yes, I could be wrong.

It was my understanding that birds had such small surface are that the electricity couldn't go anywhere.

A human on the other hand has a much larger surface area for the electricity to dissipate from.

Of course voltage playes a factor since a lower voltage can't make that transition.

Yes?


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## Subzer0IsGG (Sep 14, 2012)

sarness said:


> I'm usually only wrong once a year, and the year is almost over with, so yes, I could be wrong.
> 
> It was my understanding that birds had such small surface are that the electricity couldn't go anywhere.
> 
> ...


Are you an electrician or?
The lines are not grounded to anything, so there is no path for the electricity to flow thru. We, humans could stand or hang on the wire and not get electrocuted. But if you would touch the wire and the ground or a building our the other line you would get zapped.


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## Legacyelectric (Sep 9, 2012)

sarness said:


> I'm usually only wrong once a year, and the year is almost over with, so yes, I could be wrong.
> 
> It was my understanding that birds had such small surface are that the electricity couldn't go anywhere.
> 
> ...


Huh?


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## electrictim510 (Sep 9, 2008)

sarness said:


> I'm usually only wrong once a year, and the year is almost over with, so yes, I could be wrong.
> 
> It was my understanding that birds had such small surface are that the electricity couldn't go anywhere.
> 
> ...


Dude, you're trippin. Put the tools down and step away from the wires.

Only wrong once a year? Well this one counts for the next 5 years. Get some real training. :thumbsup:


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## 220/221 (Sep 25, 2007)

sarness said:


> It was my understanding that birds had such small surface are that the electricity couldn't go anywhere.
> 
> A human on the other hand has a much larger surface area for the electricity to dissipate from.
> 
> ...


No.

Electricity (the flow of electrons) can't go *into* you. It will go *thru* you though. If a bunch of it goes thru you, you dead.

Generally, If you are not "grounded" you are safe.

Disclaimer: General terms^ for the rookie.


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## ibuzzard (Dec 28, 2008)

sarness said:


> I'm usually only wrong once a year, and the year is almost over with, so yes, I could be wrong.
> 
> It was my understanding that birds had such small surface are that the electricity couldn't go anywhere.
> 
> ...


You' re scaring me, Bro.Someone should card you,for your own good.Are you really a contractor?


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## Legacyelectric (Sep 9, 2012)

sarness said:


> I'm usually only wrong once a year, and the year is almost over with, so yes, I could be wrong.
> 
> It was my understanding that birds had such small surface are that the electricity couldn't go anywhere.
> 
> ...


Surface area is irrelevant. The bird is not a part of a circuit. He is energized to the same potential as the bare wire he's perching on, but he's oblivious to that because there is no path through him to source, or ground. There are some good resources online discussing electrical theory. You should research voltage, current, and resistance and how they interrelate in a circuit. As well as conductor vs insulator. 

It's dangerous enough working with electricity, the best measure of safety starts with a basic understanding of electrical theory.


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## electrictim510 (Sep 9, 2008)

"I'm usually only wrong once a year"

We'll have that put on your grave when it catches up to you then. :thumbsup:


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## Legacyelectric (Sep 9, 2012)

Cut the wire between his two feet and if he could magically hold both ends up and apart he's dead, if he had long legs and could put one foot on one phase and one on the other he's dead, if he had a long piece of copper in his mouth and it was touching ground he's dead. There has to be a path THROUGH him, not INTO him.


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## etb (Sep 8, 2010)

Subzer0IsGG said:


> Are you an electrician or?


Are YOU an electrician or? How many other electricians on ET start posts about how impossible it is to get hung up on 120?


Every person on the internet answers the question about hanging on a HV line as "no, you won't get shocked as long as you're not grounded." But there could easily be more to the story.

Your body is a capacitor and it's value changes with applied voltage. Go learn about linemen who repair walk down the transmission lines. When the chopper approaches they reach out a ground wand. At then end you'll see a monster arc as they bring their chopper to the potential of the line. The arc is continuous since that potential is changing 120x a second. The reason there is an arc at all is because the chopper has a conductive mass. Simple electrostatic potential that starts the arc; resulting current is sustained because the air has broken down and is conducting current to the chopper that is a capacitor. That is your first clue: that if somehow you jumped out of a building and hung on a line, you'd get shocked as you made contact. Is your capacitance as large as the choppers? No. Is it large enough to pass current? I have no idea but it's obviously possible.

The linemen wear metal mesh suits so their whole body is the same potential. That is the second clue: that if you managed to hang on after getting shocked the first time, you still have the problem that your body is a capacitor...a distributed one. Each point on the wire goes up and down in potential at the same time, even if the wire is a dead end; your body has to do the same. But as it energizes to one polarity and then reverses 120x a second, the capacitance creates a potential between your hands and everything else until the electrons flow to the other end and then polarity reverses, just like a cap in any AC circuit. I have no idea the magnitude of this current, but one could assume it to be lethal.

Third, on a high enough voltage line, it's possible that you'd be passing some ionization current.

I think that until mythbusters tests this out with a full instrumented cadaver, the debate is far from settled.


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## RGH (Sep 12, 2011)

question for you younger guys.....do they show you the death film in school..?....this was part of class I took several years ago....back in 1980 we didn't have these kinds of things...it was 2005 and I was taking a class on the '05 updates...the instructor showed us this film as a bonus so to speak...said it was required safety film now...just a bunch of home videos laced together of people getting electrocuted....was nasty stuff...mostly people filming family members after storms ect...flooded basement guy walking through 3 feet of water showing chit and pow...dude washing his jeep in barefeet extension cord gets wet pow....EMS guy at an accident stands up gets powerline to head nasty nasty...car had hit pole tv station was taping wow...


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## sarness (Sep 14, 2010)

Thanks etb, I think that's what my understanding was but didn't have the terms right.

I'm not a full time electrician, I do work with it and know enough to respect it.

I'm not here to just laugh at some of the squabbles that go on, but learn a thing or too. I really enjoy reading some of the posts, especially the things you come across on service calls.

I still learn something new each day, today was no different.


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## Legacyelectric (Sep 9, 2012)

I think in that case it's the helo arcing to the line? Helo will arc to any grounded surface because of the static charge that accumulates from the rotors. And I think you're unlikely to see a bird perched on an energized 345kV interstate transmission line, I would think the EMF would be a little tingly at that voltage. was under the assumption we were talking smaller distribution lines like the ones we always see birds on. I could be wrong, and often am. Way more than once a year!


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## Subzer0IsGG (Sep 14, 2012)

Legacyelectric said:


> I think in that case it's the helo arcing to the line? Helo will arc to any grounded surface because of the static charge that accumulates from the rotors. And I think you're unlikely to see a bird perched on an energized 345kV interstate transmission line, I would think the EMF would be a little tingly at that voltage. was under the assumption we were talking smaller distribution lines like the ones we always see birds on. I could be wrong, and often am. Way more than once a year!


Lol. Icwutudidthere
And yes, I agree. Justregular trans lines I thought too


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## bobelectric (Feb 24, 2007)

One hunting day my Buddy said the fence is off. It wasn't and I got hit 1 click below my nods, 3 times.


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## black (Oct 12, 2011)

It is deadly. Other factors like amperage, the path the electricity takes through the body, how long the person is a part of the circuit, and whether the power is AC or DC matter, but 120v absolutely constitutes a lethal danger.


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## mnelectrician (Dec 1, 2008)

electrictim510 said:


> I do that test also as long as I have no meter to test if it's dead. Short path that doesnt go through the heart I fugure it is a little safer...


I hope you're kidding and don't work without using a meter.


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## Subzer0IsGG (Sep 14, 2012)

Seems my first thread was a huge success. 17+ pages.
Your welcome


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## electrictim510 (Sep 9, 2008)

mnelectrician said:


> I hope you're kidding and don't work without using a meter.


I rarely test wires without a meter, but if you ever tested live wires with one hand like this you would see why it's no big deal.


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## Tsmil (Jul 17, 2011)

3 rules with working with 120 live. 


1. If you are unsure if it is safe, shut it off.
2. If you think it's safe, shut it off. 
3. If you know it's safe, you're an idiot.


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## jrclen (Oct 23, 2007)

Legacyelectric said:


> The only tick tracer I've found that is both reliable, and correct all the time is the fluke.


My brand new fluke has lied to me twice now. The old one never did. 

The first time, I was checking to make sure a fixture romex was dead. When I cut it, I found out the fluke lied.

A couple days later I stuck the fluke into a light socket. It showed no power. Being leery, I screwed in a bulb. Fluke lied again.

This one has an on off button, but it flashes every few seconds when it's turned on so you know it's turned on. My greenlee liked to turn itself off in the middle of a job. It didn't take me long to throw that one in the trash.


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## Legacyelectric (Sep 9, 2012)

jrclen said:


> My brand new fluke has lied to me twice now. The old one never did.
> 
> The first time, I was checking to make sure a fixture romex was dead. When I cut it, I found out the fluke lied.
> 
> ...


I have the one with on off button and the red light heartbeat, an older one. The NEW ones have a round end on them!? You can't stick them in an outlet. I'm guessing this is because of tamper proof outlets? Other than that its stupid.


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## jrclen (Oct 23, 2007)

Mine has the flat end. Yeah the tamperproofs rule out poking a contact tester into them.


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## chicken steve (Mar 22, 2011)

Tsmil said:


> 3 rules with working with 120 live.
> 
> 
> 1. If you are unsure if it is safe, shut it off.
> ...


 
the prob with 120V is, it's usually the most unspecified via panel schedules, if one is in fact filled out _at all_

so on those resi serv calls , where it's evident that more time will be spent isolating the breaker than performing whatever fix is requested , i just shut off the main

~CS~


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## bobelectric (Feb 24, 2007)

www.GradingandExcavation.com has areal good safety article on the Myths of Electricity.


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## Shockdoc (Mar 4, 2010)

Not deadly enough to kill me yet.......


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## jimmy21 (Mar 31, 2012)

This thread reminded me of something. One time I was working at a casino and the excavation crew came up to our forman and said "we hit one of your conduits but Im pretty sure the wires are fine because I was poking a screwdriver in the hole I made and the wires don't feel damaged. Forman goes and looks and comes back. "They were sticking a screwdriver in a conduit with live (I don't remember the voltage but it was several thousand volts) while standing in a foot of water and mud"


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## MNDan (Mar 14, 2010)

Subzer0IsGG said:


> Caught up on 120...I just find that hard to believe, that doesn't tend to happen in 120
> You must of cut the hot and common at the same time which made a short?
> If you had boots on and cut one wire you would have no problem


 


You're a moron.


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## Legacyelectric (Sep 9, 2012)

120 hurts, can kill. But I'll tell you what is really stupid... Fooling with a running package unit and getting hit by a 440 capacitor. That hurts really bad. (I'm the stupid one).


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## Subzer0IsGG (Sep 14, 2012)

MNDan said:


> You're a moron.


Obviously you are you dumb****. You come here with nothing intelligent to say. While everything I've typed is relatively true. 
Grow up and learn a thing or two. Obviously you know nothing.


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## wildleg (Apr 12, 2009)

181 posts and this idiotic thread is still going strong

IBTL !!


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## Zog (Apr 15, 2009)

wildleg said:


> 181 posts and this idiotic thread is still going strong
> 
> IBTL !!


And about 175 of those post contain wrong info.


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## Subzer0IsGG (Sep 14, 2012)

Zog said:


> And about 175 of those post contain wrong info.


Ok genius, enlighten us.


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## CopperSlave (Feb 9, 2012)

Subzer0IsGG said:


> Ok genius, enlighten us.


I'd suggest you sit back and read some more on this forum before before you make too many more smarta$$ remarks to respected members here.


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## Subzer0IsGG (Sep 14, 2012)

CopperSlave said:


> I'd suggest you sit back and read some more on this forum before before you make too many more smarta$$ remarks to respected members here.


No thanks. I find it amusing when people make remarks like that but yet don't shed any info which to prove what their saying.
Now, if your siting there telling me the bigger your post count the bigger your epeen therefore I must follow and adhere to what you say, then you have another thing coming.


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## CopperSlave (Feb 9, 2012)




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## Subzer0IsGG (Sep 14, 2012)

If you were to stop kissing ass you'd realize zogs post was a troll post.


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## Mike D (Sep 16, 2008)

WOW. This thread is still kicking?
Amazing information being shard on this one.

Cletis dont need no stinken meter!


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## Legacyelectric (Sep 9, 2012)

Zog said:


> And about 175 of those post contain wrong info.


Amen.


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## Mike D (Sep 16, 2008)

Canadians got smooth moves.

http://www.youtube.com/watch?feature=player_embedded&v=j_-MsDSAW0Y


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## Zog (Apr 15, 2009)

Subzer0IsGG said:


> No thanks. I find it amusing when people make remarks like that but yet don't shed any info which to prove what their saying.
> Now, if your siting there telling me the bigger your post count the bigger your epeen therefore I must follow and adhere to what you say, then you have another thing coming.


Do you really think you are the first person to ever bring this topic up? Do I really need to go through explaining it everytime some newbie shows up here and asks the same stupid question? Or maybe you could just search old threads for the subject, or better yet do your own reasearch. 

Oh, and by the way, I spent 15 years researching the subject and providing training to engineers and electricians all over North America, have been called on many times as an expert witness in electrical injury cases, and have published several articles and IEEE papers on the subject. 

Now if you ever would like any help learning about anything, which obviously you have a lot to learn about, I suggest you check your attitude at the door next time you post.


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## Subzer0IsGG (Sep 14, 2012)

Zog said:


> Do you really think you are the first person to ever bring this topic up? Do I really need to go through explaining it everytime some newbie shows up here and asks the same stupid question? Or maybe you could just search old threads for the subject, or better yet do your own reasearch.
> 
> Oh, and by the way, I spent 15 years researching the subject and providing training to engineers and electricians all over North America, have been called on many times as an expert witness in electrical injury cases, and have published several articles and IEEE papers on the subject.
> 
> Now if you ever would like any help learning about anything, which obviously you have a lot to learn about, I suggest you check your attitude at the door next time you post.


no, I do not believe I'm the first to bring it up on this site, but yes. I'm the first to bring it up since I joined. Now if all your going to do is brag and showboat what you claim to know without showing any of your work here then I cbf'd with what you have to say. You claim 175 posts are incorrect? Ok, show me. You havn't done one ****ing thing besides tell me you've wasted fifteen years researching something that apparently described by you is so trivial and newbyish that it shouldn't be asked. I never claimed that I know it all, and am always willing to learn more. But with self righteous assholes like yourself, posting nothing but spam here help nothing.


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## Legacyelectric (Sep 9, 2012)

Subzer0IsGG said:


> no, I do not believe I'm the first to bring it up on this site, but yes. I'm the first to bring it up since I joined. Now if all your going to do is brag and showboat what you claim to know without showing any of your work here then I cbf'd with what you have to say. You claim 175 posts are incorrect? Ok, show me. You havn't done one ****ing thing besides tell me you've wasted fifteen years researching something that apparently described by you is so trivial and newbyish that it shouldn't be asked. I never claimed that I know it all, and am always willing to learn more. But with self righteous assholes like yourself, posting nothing but spam here help nothing.


It is troubling to read incorrect assumptions and theories about something as serious as death by electrocution. 

I admit that I am not the resident expert on capacitive coupling, or its ramifications regarding how electric current and or voltage will behave in any situation where a person becomes energized, but I can tell you that very good information has been shared about how electrocution typically happens, and how to avoid it in 99% of situations you are likely to encounter. 

I would never call you a moron, but I can assure you that you have some serious misconceptions about electricity and how it behaves in MOST circumstances. 

I too am relatively new on here and I am learning a lot from those who are more experienced, and I think that is the point of this forum. Not to defend our own preconceived ideas.


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## Subzer0IsGG (Sep 14, 2012)

Legacyelectric said:


> It is troubling to read incorrect assumptions and theories about something as serious as death by electrocution.
> 
> I admit that I am not the resident expert on capacitive coupling, or its ramifications regarding how electric current and or voltage will behave in any situation where a person becomes energized, but I can tell you that very good information has been shared about how electrocution typically happens, and how to avoid it in 99% of situations you are likely to encounter.
> 
> ...


I hear yea. but please, point out these serious misconceptions you claim that I have, then we'll debate it. Thats how it works.


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## Subzer0IsGG (Sep 14, 2012)

This thread apparently has turned into + 1' s and troll thread only. Get them while its hot


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## 220/221 (Sep 25, 2007)




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## Legacyelectric (Sep 9, 2012)

Subzer0IsGG said:


> I hear yea. but please, point out these serious misconceptions you claim that I have, then we'll debate it. Thats how it works.


You know what subzero, I owe you an apology. The posts I read that freaked me out the most were actually by "sarness". I somehow confused you and that guy. I apologize. The only one I read by you that I think needs clarification was the one about cutting both hot and neutral causing a short and thereby increasing the chances of electric shock. I don't really understand how that would be the case. 

Again, my apologies.


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## Legacyelectric (Sep 9, 2012)

What is a "troll"????


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## Shockdoc (Mar 4, 2010)

120 volts wasn't too deadly back in the 30s and 40s when electricians were trained to use two fingers to test it. Why is it so deadly now that it needs to get turned off to replace a switch while wearing PPE ???


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## Subzer0IsGG (Sep 14, 2012)

Legacyelectric said:


> You know what subzero, I owe you an apology. The posts I read that freaked me out the most were actually by "sarness". I somehow confused you and that guy. I apologize. The only one I read by you that I think needs clarification was the one about cutting both hot and neutral causing a short and thereby increasing the chances of electric shock. I don't really understand how that would be the case.
> 
> Again, my apologies.


Ahh yes, well, I thank you for being the bigger man there. I was taking a shot in the dark saying he cut both those wires, to be honest I had no idea, thats what trouble shooting is about. And, troll post or trolling is just excessive inflammatory posts. Or just a bunch of off topic posts.


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## SVT CAMR (Apr 17, 2012)

120 will kill you. Just depends how many amps are flowing and how well you are grounded. I have been held by it as a young helper. I was on top of a walk-in cooler and had my arm wrapped around a bar joist. I felt the hum inside my head that felt like I was held for a minute..... Even had enough time to think how I'm going to break free. To say the least it surprised me. After that my eye pulsated for at least a week.  It was a real wake up call for me. I could only imagine if it was 277v and a big lighting load. It comes down to how well you are grounded when it comes to the small stuff. Then we can have a whole other conversation about getting hit and falling. Thats another way to kill yourself.


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## Zog (Apr 15, 2009)

Subzer0IsGG said:


> no, I do not believe I'm the first to bring it up on this site, but yes. I'm the first to bring it up since I joined. Now if all your going to do is brag and showboat what you claim to know without showing any of your work here then I cbf'd with what you have to say. You claim 175 posts are incorrect? Ok, show me. You havn't done one ****ing thing besides tell me you've wasted fifteen years researching something that apparently described by you is so trivial and newbyish that it shouldn't be asked. I never claimed that I know it all, and am always willing to learn more. But with self righteous assholes like yourself, posting nothing but spam here help nothing.


AHH, to be young and know everything again. :001_huh:


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## Zog (Apr 15, 2009)

Shockdoc said:


> 120 volts wasn't too deadly back in the 30s and 40s when electricians were trained to use two fingers to test it. Why is it so deadly now that it needs to get turned off to replace a switch while wearing PPE ???


Uh yes it was, check the BLS website for year by year statistics, fatalities in the electrical industry have fallen nearly every year for the last 30 years, thanks to regulations and training.


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## Zog (Apr 15, 2009)

SVT CAMR said:


> 120 will kill you. Just depends how many amps are flowing and how well you are grounded. I have been held by it as a young helper. I was on top of a walk-in cooler and had my arm wrapped around a bar joist. I felt the hum inside my head that felt like I was held for a minute..... Even had enough time to think how I'm going to break free. To say the least it surprised me. After that my eye pulsated for at least a week.  It was a real wake up call for me. I could only imagine if it was 277v and a big lighting load. It comes down to how well you are grounded when it comes to the small stuff. Then we can have a whole other conversation about getting hit and falling. Thats another way to kill yourself.


The amount of load on a circuit has no effect to an electric shock, that is a very common misconception.


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## Zog (Apr 15, 2009)

For the benifit of the "Entitlement generation" that needs someone to do everything for them (God help our country) here is what I told the last kid that asked that question. This is just the basics, go do some research if you have questions, Dr Morse's research on DEI is excellent, oh wait that would be too much to ask. 

There are several factors that determine the severity of an *electric* *shock

*1. Amount of Current
The amount of current that passes through the body during an electrical *shock* is a large factor when determining the amount of tissue damage that will occur. The table listed below shows some values and their effects.

*CURRENT*

*60HZ*


*PHYSIOLOGICAL*
*PHENOMENA*
*FEELING OR LETHAL*
*INCIDENCE*
< 1mA​None
Imperceptible

1mA​Perception threshold


2-10mA​Sensation of *shock*
Not painful, muscle control maintained

5mA​
Ground Fault Circuit Interrupter Operates

10-20mA​Paralysis Threshold of Arms
Cannot release hand grip, victim may be thrown clear (may progress to higher current and be fatal)

20-50mA​Respiratory Paralysis
Breathing Stoppage (frequently fatal)

50-100mA​Fibrillation Threshold (0.5%)
Heart action discoordinated (probably fatal)

100-200mA​Fibrillation Threshold (99.5%)

>200mA​Tissue Burning
Non fatal unless vital organs are burned


*2.Current Path*

A vital aspect of electrical *shock* is the pathway through the body that the current will take. The current path will determine which tissue and organs will be damaged or destroyed. However it is important to remember that current takes all paths, the damage to the human body is not simply between the entry and exit points.Often a *shock* victim is spared because the current path does not pass through a vital organ. For example, a foot-to-foot path is less likely to result in fibrillation than a hand-to-hand path because there is no current flow through the heart. 

3. *Duration*
The amount of time that the current passes through the body plays a significant factor in the outcome. We discussed earlier that a 100mA *shock* is the value that OSHA uses as a fatal *shock* level, but as the duration increases the amount of current that can be fatal decreases exponentially. One-way to avoid getting stuck on a circuit is to use the back of your hand. Since AC causes the muscles in your forearm to contract, you may grasp onto a conductor upon getting shocked. By using the back of your hand, the contracting muscles may cause you to pull away. Studies have shown that at voltage levels above 2300V, an arc is drawn to the hand, causing you to retract before grasping on to the conductor or circuit part.

*4.*Body resistance
As discussed, the level of current is the factor that will determine the extent of the injury from an *electric* *shock*. But the resistance of the human body is the variable that we can control to limit the current level. Ohms law applies to human *shock*, the amount of current that flows through the body will be determined by the voltage the person contacts divided by the body resistance. The resistance of the human body can vary dramatically depending on several factors. Essentially it is the skin, along with such factors as area of contact, tightness of contact, dryness or wetness of the skin, and cuts, abrasions, or blisters that introduce the variables.Excluding the skin, human body resistance is about 250 Ohms per arm or leg, and 100-500 Ohms for the torso. The more muscular the person, the lower the resistance. Unless the skin is punctured, the skin will provide additional resistance. The worst-case scenario is considered to be 500 Ohms hand-to-hand. Some typical values of skin resistance are listed below.


*Condition of contact*

*Resistance (Ohms)*
*Dry*
*Wet*​Finger touch

40 k-1 M
4-15 k​Hand holding wire

15-50 k
3-6 k​Finger-thumb grasp

10-30 k
2-5 k​Hand holding pliers

5-10 k
1-3 k​Hand around pipe (or drill)

1-3 k
0.5-1.5 k​Palm touch

3-8 k
1-2 k​Two hands around pipe

0.5-1.5 k
250-750​Hand immersed

--------
200-500​Foot immersed

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100-300​

Using these typical values, a person can estimate their approximate body resistance. Let’s say a person grabs a wire in a 480/277V panel that they assumed was deenergized while touching the panel door with the other hand. The worker would have about:

250 ohms for the arm +
250 Ohms for the other arm +
32,500 Ohms for the skin
A total resistance of about 33,000 Ohms

277V/33,000 Ohms = 8.4 mA (Mild *shock*

Now lets look at the same scenario, but this time with wet or sweaty skin.

250 ohms for the arm +
250 Ohms for the other arm +
4500 Ohms for the skin
A total resistance of about 5000 Ohms

277V/5000 Ohms = 55.4 mA (Respiratory Paralysis, possible fibrillation, may be fatal)

At voltage levels above 600V, the resistance of the skin ceases to exist; it is simply punctured by the high voltage. For higher voltages, only the internal body resistance impedes current flow. At levels about 2400V and higher, burning becomes the major effect, lower voltages fibrillation and asphyxiation.

How well you are grounded is also a factor. Wearing rubber soled shoes or gloves along with the material between you and ground will add to your total resistance. 



*Voltage*
For any given voltage the current passing through a body will be equal to volts divided by body resistance, however, higher voltages affect the path due to the “Skin effect”. High voltages (>20,000V) cause current to flow primarily on the outside of a conductor therefore a *shock* victim from these higher voltages will see more external burns to the skin and less of an effect on the internal organs.

*Frequency*
Studies have shown that the frequency best suited for traveling through the human body is 50-100 hertz. Higher frequencies (>200Hz) also have a “Skin effect” similar to that discussed above.

*AC vs. DC*
AC and DC also affect the body in different ways. AC tends to cause a muscular contraction that can cause the victim to grab hold of a conductor while DC tends to cause a convulsion effect causing the victim to jerk away. The minimum “let-go” current for AC is about 15mA while the DC “let-go” current is significantly much higher at 75mA.


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## Frasbee (Apr 7, 2008)

America's entitled generation started sometime in the 1930's.


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## gottspeed (Mar 8, 2010)

This guy doesn't represent Alberta.

We have a good economy here and they'll let anybody in the trade.


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