Power line inspection - up close and personal!!

That's cool....

Any idea what causes the electricity to jump to the wand he holds, and why he does that?
 
SkyHog said:
Any idea what causes the electricity to jump to the wand he holds, and why he does that?
Click to expand...
The wire is alternating between + 500,000 volts and -500,000 volts 60 times a second. The helicopter is close to neutral voltage. When connected, the helicopter becomes like a capacitor, storing electrical energy first at + voltage, then at - voltage. The spark you see is the flow of current into and out of the helicopter to charge it/discharge it. It is a pretty big spark due to the voltages involved but pretty low amperage. Once they clamp the bonding strap on the wire, all that spark energy flows through the bonding strap.

Why did he do that? Probably at least partly for show. When the camera isn't there, I bet they just fly up and hit it with the wand, not hold the wand off to see the spark. But you do want a metal to metal contact prior to grabbing the cable or even getting your hand near it with the big clamp. That spark can jump a long way. So how much do you trust your faraday suit? LOL!

-Skip
 
Skip Miller said:
The wire is alternating between + 500,000 volts and -500,000 volts 60 times a second. The helicopter is close to neutral voltage. When connected, the helicopter becomes like a capacitor, storing electrical energy first at + voltage, then at - voltage. The spark you see is the flow of current into and out of the helicopter to charge it/discharge it. It is a pretty big spark due to the voltages involved but pretty low amperage. Once they clamp the bonding strap on the wire, all that spark energy flows through the bonding strap.

Why did he do that? Probably at least partly for show. When the camera isn't there, I bet they just fly up and hit it with the wand, not hold the wand off to see the spark. But you do want a metal to metal contact prior to grabbing the cable or even getting your hand near it with the big clamp. That spark can jump a long way. So how much do you trust your faraday suit? LOL!

-Skip
Click to expand...

Interesting...I wonder, then, if it works like a capacitor, if it went and landed fairly quickly after leaving the wires, if someone touched the helicopter while it was coming down, if he'd get electrocuted.
 
SkyHog said:
Interesting...I wonder, then, if it works like a capacitor, if it went and landed fairly quickly after leaving the wires, if someone touched the helicopter while it was coming down, if he'd get electrocuted.
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Potentially. (pun not intended) But from the moment the helo moved away from the wire, its static charge would begin to dissipate through normal means. Do helos have static wicks? :dunno: On a humid day the static charge would dissipate rather quickly.

-Skip
 
I met a guy who flew the 500 in construction, he would thread some type of bobbin with a lance at the top of these poles. Then they would drag a rope through, and that was used to pull the cable.
If you saw him at the end of his day, it was amazing how wired was, he was a bundle of nervous energy, jabbering and twitching all over the place- I guess it was the result of such tedious and high risk work.
 
Skip Miller said:
Why did he do that? Probably at least partly for show. When the camera isn't there, I bet they just fly up and hit it with the wand, not hold the wand off to see the spark. But you do want a metal to metal contact prior to grabbing the cable or even getting your hand near it with the big clamp. That spark can jump a long way. So how much do you trust your faraday suit? LOL!

-Skip
Click to expand...
Exactly right. I've talked to lineman who work from bucket trucks and when they touch a high tension line then grab it hard and quick to reach the same potential quickly. When approaching a line like this you really don't want to dilly dally around...:eek: Like you said, touching 500,000 volts is not for the faint of heart.
 
Ok...I cannot figure out which one of those two has the bigger balls! WOW that is just amazing....
 
My Dad, who has now got 50 (yes 50!) years at the Georgia Power Company, was one of the first people to ever work 500KV "hot".
Ga Power is considered the pioneer of the techniques of doing such stuff. Everyone I know ( I worked there 4 years) who has ever worked transmission lines vastly prefers to work it that way. I'll have to find and scan a picture of him in his "monkey suit" on a live wire. They called the suits that because the bonding tether on early suits came of the suit at the seat. On some days, you can draw a 12 or 14 inch arc from your tether.
 
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