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Episode Description
Fabian Giesen
X: https://x.com/rygorous?lang=en
The Ryg Blog: https://fgiesen.wordpress.com/
GitHub: https://github.com/rygorous
YouTube: https://www.youtube.com/channel/UCcRaa0AcYX32c0m8wJJHNWg/videos
Fabian’s addendum:
This is a 500kV switch disconnecting under load
https://www.youtube.com/watch?v=GMbN9nb3qykand
this is why it was filmed:
https://capturedlightning.com/frames/longarc.htm#500_kV_Switch
Note especially this section near the end:After this event, it was determined that both SF6 switch bottles in the affected phase had sustained permanent damage. The bottles were sent back to the manufacturer for analysis to determine why the interrupter failed. Loss of pressurized SF6 gas inside one of the interrupter bottles was determined to be the root cause of the initial switching failure. When the SF6 became depleted, the internal arc (created when the breaker tried to open) could not be extinguished. The circuit remained connected, through the internal arc, triggering the fault and incredible display. As impressive as this huge arc may be, the air break switch was NOT disconnecting a real load. This arc was "only" carrying the relatively low (about 100 amps) magnetizing current associated with the line reactor. The 94 mile long transmission line associated with the above circuit normally carries over 1,000 megawatts (MW) of power between Boulder City, Nevada (from the massive generators at Hoover Dam) to the Lugo substation near Los Angeles, California. A break under regular load conditions (~2,000 amps) would have created a MUCH hotter and extremely destructive arc. Imagine a fat, blindingly blue-white, 100 foot long welding arc that vaporizes the contacts on the air break switch and then works its way back along the feeders, melting and vaporizing them along the way.A bit less sobering, this shows the raw signal from a mechanical switchwithout debouncing:
https://www.youtube.com/watch?v=e1-kc04jSE4
I said it wrong in the podcast, this happens in both directions, and as you can see it takes extra processing to get rid of it.
Wookash Podcast
Show links: https://podcasters.spotify.com/pod/show/lukasz-sciga
Spotify: https://open.spotify.com/show/7tExkDJcI6vvmpCguX8YgdApple
Podcasts: https://podcasts.apple.com/us/podcast/wookash-podcast/id1683109481
Youtube: https://www.youtube.com/channel/UC9J9u3apteD0EuFjzRpt71w