Arcs and Sparks.

[mixedgas]

Worth viewing:


http://www.youtube.com/watch?v=34r6RGF2JLA#t=0

The wind is driving an arc between two phases of a three phase power line back towards the transformer. The speed of the arc's travel is limited by how fast it can heat the cable to burn off a thin insulation on the cable.

If you ever get the notion that line power is pure, keep in mind stuff like this goes on system wide all the time.

It is unusual to get a sustained moving arc like this in a power line. Usually a safety fuse blows or a overcurrent interrupter trips in the system. I have watched small stationary arcs run for hours.

Steve

[buffo]

Saw that on Reddit over the weekend. High-impedance fault, so it didn't trip the feeder at the sub-station.

I would definitely shit my pants if I saw that in real life though!

Adam

[tonyaztec]

Awesome

I would definitely shit my pants if I saw that in real life though!

Me too, I love watching videos like that on Youtube.

[buffo]

This one here is a good bit worse:



Adam

[Galvonaut]

Wow, that's like a horizontal Jacob's ladder.

I was happy with my 10kV one running up some old metal clothes hangers but think I'd stand back of this too!

Keith

[tonyaztec]

Got me all excited now..

http://www.youtube.com/watch?v=yX5TIDLvMyw

[dream beamz]

Good thing he didn't pick up the home phone when it was ringing. Would have gotten a more than 24 volt surprise

[JohnYayas]

Saw something very similar in high school once. It was during football practice and there were some power lines across the street from the field. The kicker was practicing field goals and he kicked the ball far enough so that it bounced off one of the power lines. It made it the wire move so close to the other one that it started to arc. For a bit the power line was oscillating up and down like a spring between the two poles and the arcs were moving with it. It lasted no more than a few seconds and then the transformer blew. Some old lady across the street came out of her house with a cigarette and yelled something like "Whoever knocked the damn power out better turn it back on!" It was pretty scary because I was the trainer on the team and I happened to be out in the street catching the field goals at the time. So, I got an up close view of it all.