you don't get shocked if you touch only the hot screw on outlet?

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4x4dually said:
Lots of things affect the body's ability to carry current....with skin moisture/sweat being one of the heavy hitters, literally. Tell your employee to stop being stupid and turn stuff off before he touches it. That's just dumb.
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Is smart to turn it off before working on it.

Also is smart to understand why it sometimes doesn't shock you.

In wood constructed building most the time you are not grounded unless you are in contact with some grounded object within the building, like an appliance frame, or the yoke of a device you happen to be working on. But if standing on wood/carpet/other non metallic floor covering and simply touch the "hot conductor" with just one hand, normally there is no low enough resistance path that you will have enough current pass through you to feel it, that is simple Ohm's law stuff there. What does get people that get too confident with this is becoming grounded somewhere and not knowing it, or getting in a path, touch the incoming "hot" and also touch the outgoing "hot" lead to an open switch and if there is a connected load you still get shocked because you put yourself in the circuit path.
 
ggunn said:
And then there are these guys.

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Good example showing you don't get shocked when not subjected to something of different potential.

That said I've seen this and/or other similar videos a few times and got to wondering if that is a real job or not. Maybe once was but seems it could be done by drones these days. I would think insulators and connections are what needs inspecting more often than conductors in mid span need it as well.
 
kwired said:
Good example showing you don't get shocked when not subjected to something of different potential.

That said I've seen this and/or other similar videos a few times and got to wondering if that is a real job or not. Maybe once was but seems it could be done by drones these days. I would think insulators and connections are what needs inspecting more often than conductors in mid span need it as well.
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It’s a real job and It’s still done daily
 
kwired said:
Is smart to turn it off before working on it.

Also is smart to understand why it sometimes doesn't shock you.

In wood constructed building most the time you are not grounded unless you are in contact with some grounded object within the building, like an appliance frame, or the yoke of a device you happen to be working on. But if standing on wood/carpet/other non metallic floor covering and simply touch the "hot conductor" with just one hand, normally there is no low enough resistance path that you will have enough current pass through you to feel it, that is simple Ohm's law stuff there. What does get people that get too confident with this is becoming grounded somewhere and not knowing it, or getting in a path, touch the incoming "hot" and also touch the outgoing "hot" lead to an open switch and if there is a connected load you still get shocked because you put yourself in the circuit path.
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Tee grid ceilings get most commercial guys!
 
Your body can, under the right circumstances, act like a large capacitor and the capacitor charging current flows at the available fault current in a system until the capacitor is fully charged. No ground connection is needed. So when that happens, it can kick your ass or disrupt your heartbeat. Every time he does that he is literally betting his life on those complex circumstances being unfavorable to making him into a good capacitor.

The lineman videos have to be watched in context. The first part of the video is always of them using a conductive rod to equalize the capacitive potential of the helicopter to the line. There is quite a spark involved. Then too the linemen are wearing a special suit that acts as a faraday cage so that any stray capacitance to ground, even at those extreme distances, causes current to flow over their body, not through it. “Birds on the Wire” is basically OK because the bird’s body mass is so small and the distance to ground is so far that it isn’t a very good capacitor at the 50kV and under distribution voltages. But on the 500kV transmission lines, birds can indeed be killed.

Bottom line, it’s just not something to play with…
 
MattG0311 said:
Let’s not tempt fate…120 volts has killed plenty of people.
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gadfly56 said:
I already have Afib. I'll pass.
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I don't have atrial fibrillation, and I'm certainly not going to intentionally do anything that might bring it on.

Any idea how often people are killed or injured by a 277-volt lighting circuit that they didn't realize wasn't a "harmless" 120-volt circuit? I'm thinking of the volunteer maintenance guy at the church of my childhood. He didn't have much of a clue, but he worked cheap.
 
kwired said:
Good example showing you don't get shocked when not subjected to something of different potential. ...
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Actually, it's an example of using a Faraday-cage suit because empty space has a sufficiently different potential for harmful currents to flow.

If the other conductor of a 765-kV transmission line is 10 meters (?) away, that's a 76.5 kV/m voltage gradient. Not to be trifled with, nor approached casually.

I don't think I've ever seen a bird on a wire on a 765 kV transmission line. Or even on a 15 kV residential distribution line. Only the insulated 120/240 volt and low-voltage voice/data/video lines.
 
drcampbell said:
Actually, it's an example of using a Faraday-cage suit because empty space has a sufficiently different potential for harmful currents to flow.

If the other conductor of a 765-kV transmission line is 10 meters (?) away, that's a 76.5 kV/m voltage gradient. Not to be trifled with, nor approached casually.

I don't think I've ever seen a bird on a wire on a 765 kV transmission line. Or even on a 15 kV residential distribution line. Only the insulated 120/240 volt and low-voltage voice/data/video lines.
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I see them all the time on 12.47kV lines that are typical rural distribution lines here, sometimes large numbers of birds and the lines sway if they all suddenly take off about the same time. Most likely seen them on at least up to 69kV transmission lines as well, which are also fairly common and even on same pole as the 12.47 at times. Above that voltage can't say for certain whether I've seen birds on the lines or not. There is fair amount of 115 kV lines and somewhat limited number of 345 kV lines in the area.
 
kwired said:
I see them all the time on 12.47kV lines that are typical rural distribution lines here, sometimes large numbers of birds and the lines sway if they all suddenly take off about the same time. Most likely seen them on at least up to 69kV transmission lines as well, which are also fairly common and even on same pole as the 12.47 at times. Above that voltage can't say for certain whether I've seen birds on the lines or not. There is fair amount of 115 kV lines and somewhat limited number of 345 kV lines in the area.
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Yes, Starlings can make those lines dance when they leave.
 
Hv&Lv said:
It’s a real job and It’s still done daily
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Yes, I've actually seen the guys up on a 750kV transmission line. Not only is that level of voltage a deterrent for me but also these guys were a couple of hundred feet in the air with nothing between them and the ground except the 705kV wire. No thank you.
 
Fred B said:
Yes, I've actually seen the guys up on a 750kV transmission line. Not only is that level of voltage a deterrent for me but also these guys were a couple of hundred feet in the air with nothing between them and the ground except the 705kV wire. No thank you.
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Still not getting me to do it, but I'm sure they have safety harness attached the line so they can't fall (very far)
 
Seems no matter if I’m on a second story wood framed floor with shoes on, if I contact a 120V hot wire I get zapped and I definitely feel it.
 
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