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Posted By: dougwells wow watch this - 09/22/04 02:52 AM
Not sure what to say
http://members.cox.net/kj7e1/500Kv.mpg

This was a quote that came along with the link i recieved not sure when this happened unless someone could photoshop this

" There was reportedly a problem shutting down a 500,000 volt electric utility circuit by conventional means, so the circuit was opened at the Palo Verde switchyard while under FULL load, with spectacular results. (This may be the Palo Verde Nuclear

[This message has been edited by dougwells (edited 09-22-2004).]
Posted By: hbiss Re: wow watch this - 09/22/04 04:13 AM
Somebody posted a link to a longer version of that awhile back.

-Hal
Posted By: dougwells Re: wow watch this - 09/22/04 04:27 AM
ah guess i missed that somehow
Posted By: Crowbar Re: wow watch this - 09/22/04 01:22 PM
Is it just me, or did I only see one phase of that switch arc?
Posted By: dougwells Re: wow watch this - 09/22/04 02:55 PM
Yes. I asked an acquaintance from Manitoba hydro about it. this is what he wrote.

My dept. has had numerous discussions about this very same video.
They are using a device called a circuit switcher - it consists of an air-break mechanism and vacuum chamber (vac-rupter) that is used to break/extinguish the arc under load. If I recall correctly, this cct. switcher had it's vacuum chambers fail and lose vacuum, thus severely de-rating it's interrupting capacity, they called on it to operate and break load - which it didn't really succeed in doing.

If you notice in the video, a bit closer to the camera is the 500 kv O/H buswork, if there had been a wind (or a different wind direction, for that matter), the arc would certainly have drifted into the buswork (or into the other 2 un-failed phases of the circuit switcher) and caused a 3 phase flash over with no means at all to extinguish the arc, other than the over current relays acting on the fault that would ensue when the whole structure fell, or possibly the harmonic units sensing some really ugly stuff and tripping the line via an upstream breaker.
I happen to have a sister unit to the very same circuit switcher in the video installed in one of our export stations, we use it to switch a 200 MVAR reactor bank for power factor correction, the other end of the export line I'm talking of, has the same cct switcher as well, but they use it to do the opposite - they switch in/out a 200 MVAR capacitor bank.
Posted By: Trumpy Re: wow watch this - 09/22/04 04:02 PM
Hey Doug,
How come I can't get the link to play?.
It loads WMP, but it says that the duration of the file is 00:00?. [Linked Image]
Posted By: dougwells Re: wow watch this - 09/22/04 04:11 PM
Hi Trumpy

It played in Winamp for me
Posted By: mamills Re: wow watch this - 09/22/04 04:21 PM
Doug:
What happened that finally caused the arc to be extinguished?

Mike (mamills)
Posted By: dougwells Re: wow watch this - 09/22/04 04:40 PM
Mike I am not really sure I just seen it on a forum and thought i would post it here
Posted By: mustangelectric Re: wow watch this - 09/22/04 05:49 PM
hi,
the arc could not sustain itself uder those circumstances. had the arc blast switch worked it would have extingushed or broken the arc long enough (milli seconds)and you would not have seen near the arc..

its a good thing they were clear of that line!

to view the file, try right click>save target as and save to your computer...then get your video player working...windows will work..

-regards

mustang
Posted By: earlydean Re: wow watch this - 09/22/04 06:14 PM
If you watch the film closely, at the beginning you can see the flash-over start at the right-side insulator on the phase closest to the camera. This indicates to me that maybe the insulator cracked upon opening, starting the arc that continued to give us the show.
Posted By: Attic Rat Re: wow watch this - 09/23/04 02:50 AM
... Awesome display of power!! I actually saw this in Mike Holt's newsletter a little while back!! Simply beautiful,and scary at the same time..
Russ
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