Downed power lines

Send the wife to grab them and move em out of the way for you!

Stay in your car.

Electricity does not exclusively take the path of least resistance.

Electricity does not exclusively take the path of least resistance.

You'd be much better off in a conductive full body protective suit. or in a self-propelled metal box on wheels like I said first off.

Bye. Jasen

90% of the stuff he did wouldn't work.

Bye. Jasen

maybe they were told it was safe on a mobile phone?

in some places they dress upo in metal suits annd work from use platforms suspended below helcopters to work on live high voltage lines.

for less extreme voltages insulated cherry-picker platforms are used.

Bye. Jasen

both feet should be as good as one as long as only one touches the ground at a time. running good, walking bad.

only of you're standing on the top of the ground peg (on with one foot) when you do it. if the wire fails due to too much current you're toast.

Bye. Jasen

Helicopter, not from the power Line.

Its not "ground". The term is "Equalize" and they do ot by using an insulated rod to connect a clamp to the HV cable there are preparing to work on. The other end is connected to the airframe of the helicopter. That way there is no current flow through the worker and into the airframe. There is some electrostatic dissipation from the wire, as well as the airframe and if they are at different potentials, the current flow can be fatal.

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Yes, everyone else in an "idiot", yet you come here to as the question? You post a poorly written question, then claim later that it was hypothetical. The "Idiots" don't want someone to be electrocuted, and try to explain that to you. If you had simply stated what you saw and asked if it was dangerous and how they did it, you would have got a completely different response.

TV reporters? The same type that recently parked their ENG van under high tension lines and raised their microwave antenna mast into the wires. When it didn't go all the way up, they climbed out to see why and died as their shoe touched the ground. Ironically, the door they climbed out of had the required, "DO NOT PARK THIS VEHICLE UNDER POWER LINES" warning label. As far as them walking across the downed wires, they wouldn't have been allowed to set up there if the lines weren't dead. Have you ever been in an area hit by a tornado, or lived through numerous hurricanes? That wire you saw on the ground was likely broken quite a few times between were they were set up, and the substation. If the wires touched on the way down, they would have tripped out a breaker. After a couple attempts to reset, it stops trying. This is completely different than what you asked in your first post. It took over a year to finish all the repairs around here after the last hurricane went through. There were damaged poles still leaning, and others that were cracked, but barely usable that had to remain in service, till the work could be finished. Hell, there are still a few blue FEMA tarps on some summer homes that haven't had all the repairs done because of material shortages.

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

--- No one had to. This is a public forum and any one who wants to can post anything they want to, including poorly formulated, stupid "hypothetical" questions like yours.

When you do that, you can pretty much count on getting answers warning you that your even asking the question was a testament to your moroniciousness.

---

--- Completely honest?

LOL, what would a f****ng idiot like you know about complete honesty?

---

--- Idiots like you are liable to try anything and that's why you should always be warned that what you're asking about is dangerous. Who do you think the "Don't try this at home" disclaimers on TV are for?

Bingo! Morons like you who haven't got the brains to realize what's dangerous and what's not.

---

--- Heh? I'm not the one who had to ask what the best method of dealing with a downed power line was, was I?

-- John Fields Professional Circuit Designer

On 13 Jul 2006 07:06:02 GMT, in message , Puckdropper scribed:

Absolutely. One of our safety guys does just that. He has a window-box size mockup of a power line with a couple of towers, and he has lamps connected to electrodes that he sticks in the dirt when he simulates a line fault-to-ground. He clips one end of the lamp to what would be normal ground on the system (called "remote ground" when calculating fault gradients), and sticks the other end into the dirt. The closer he sticks it to the fault, the brighter is the lamp.

Really, it's simple. It's just Ohm's law. When a power line falls, it is completing a circuit between the substation high source and the substation ground. The dirt has a higher resistance per meter than the line, so it will have most of the voltage drop. A 100A fault current and a 50 Ohms per meter soil resistance gives 5,000 volts per meter[1].

And again, the substations contain relaying that should sense these massive faults, and automatically open the line via substation circuit breaker. Key word there, *should.*

[1] That example uses a low clay soil resistivity number. Resistivity numbers for other types, say gravel or solid granite are much higher, by a couple orders of magnitude. The effect is strongly localized to the fault; the current diffuses rapidly, because the conductor is so large, and so many return paths exist, so the voltage drop gradient is steeply non-linear.

--

If life seems jolly rotten, there\'s something you\'ve forgotten,
and that\'s to laugh and smile and dance and sing!

On Thu, 13 Jul 2006 01:48:02 GMT, in message , scribed:

Yeah, munchkin, the power company turns off the source of the power. Duh.

--

If life seems jolly rotten, there\'s something you\'ve forgotten,
and that\'s to laugh and smile and dance and sing!

--- Whether his answer was sensible or not is immaterial; what you're doing is thanking him for giving you what you wanted to hear.

---

--- Surprisingly, the reason an idiot thinks that other people are idiots is because he can't understand them. Hey, that's not their fault...

---

--- So it's hypothetical and someone answers that it's perfectly safe to waak over them and one day you find yourself in a situation where you're confronted with a downed power line and you remeber that you were told that it was perfectly safe to cross, so you do. Hypothetical or not, you're still dead.

---

--- "but not I'm starting to think otherwise"?

You're really not the sharpest knife in the drawer are you?

---

--- Everyone who answered your question put some effort into thinking about it and replying, whether the reply was what you wanted to hear or not.

---

--- If _you_ use plutonium instead of uranium? That's another stupid question because that's a decision you'll _clearly_ never have to make.

---

--- No, dumbass, it was the _result_ of something stupid. Or of ignorance. A very good reason why (from the point of view of stupidity) you should stay far, far away from helicopters and power lines.

And, quite possibly, newsgroups.

-- John Fields Professional Circuit Designer

--
Duh... Because I choose to be, you top-posting twit.

--
How do you know there weren\'t any electricians there to tell them it
was OK?  Were you there?  

No, you pathetic loser, you weren\'t, You see it on TV and make all
kinds of unwarranted assumptions and walk away thinking you know
what was going on.  That\'s typical of you mindless cretins who\'ve
been brought up sucking on the glass tit.

The only sane thing to do is stay the hell away from it.

Unless you're in a car, of course, then you could just drive over it, as long as only the rubber tires touch anything.

Cheers! Rich

On Thu, 13 Jul 2006 01:48:02 +0000, tapwater top-posted:

Yes. The power company has the "off" switch.

And FYI, top-posting is rude.

Thanks, Rich

One caveat, though - don't trust those numbers that you learn "in basic electronics courses" with your life. They're NOT constants, and anything involving them should be treated with a very respectful safety margin. In other words, just because someone tells you that air breaks down at 32 kV/in (or whatever figure you're given) doesn't mean you should feel really good about being exactly 11" away from a 320 kV line...

How do you know there was no one around to tell them it was OK? Unless these people are complete idiots, I would think that the very first thing they did before setting up that shot was finding someone from the local utility company and asking, "Hey, are those things still live?"

And the main thing you're being told is that there is no single-line simple answer. The procedures for dealing with high-power electrical distribution systems fill a goodly number of large books, and are the result of long, long experience AND theory.

Bob M.

Yes, clearly it can be done.

No, you (or anyone else) can't be told how to safely do it in a simple newsgroup post.

And in this case, a little information would be far more dangerous to give out than none at all.

Bob M.

I seem to recall a statement by the producers of the "MacGyver" show that certain key elements of each of the character's "solutions" were left out on purpose, just to further the "kids, don't try this at home!" angle.

But no, the vast majority of it would NOT work as it was shown on TV. I can't imagine how many people were disappointed to find out after the fact that no, you could NOT make something that would disarm a nuclear warhead from a pickle jar, a roll of duct tape, and a $9.95 pocket calculator from K-Mart. (All put together, of course, using nothing more than MacGyver's beloved Swiss Army knife...)

Bob M.

The power company turns off the power with a switch, which breaks the line. But of course they are magic, and come from the planet Krypton, and they are the only ones that can break a line! DUH! yourselves