Cited as a reference
Jacob's Ladder: 500kV Switch Opening
Why people recommend it
Footage of a 500kV disconnect switch drawing a long arc as it opens, linked to show how far high-voltage arcs can travel.
In their words
In AC switching they will extinguish on the zero-crossing, after maximum 1/100 or 1/120 second (doesn't count for very high voltage switching), but in DC this may take longer.
stevenvh on electronics.stackexchange.com, Jul 2011. CC BY-SA.
This is a very impressive example where due to very high voltages, air temporarily acts as a conductor, where normally should be an insulator.
DimP on electronics.stackexchange.com, Oct 2016. CC BY-SA.
Well, a mere 500kV can get you a spark way bigger than 1m:
Phil Frost on electronics.stackexchange.com, Jun 2013. CC BY-SA.
