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Should earthquake, tornado, or major storm bring down high voltage power lines you might be able to use this information. You wouldn't just shoot line apart, would you?
Shown in simulation, In the middle of the United States smaller power lines are 7200 volts to ground and "12 K" phase to phase to electric company linemen with the 120 degree phase shift.
I had a question about 13,500 volt power lines ( one or two insulators on power poles for these voltages).
It is the "Device for Indicating Live Power Lines" on page 520 of the September 1930 issue of Popular Mechanics.
https://books.google.com/books?id=deIDAAAAMBAJ&pg=PA70&dq=1930+September+Popular+Mechanics&hl=en&sa=X&ved=0ahUKEwiO39KKnKfKAhVI_WMKHco-DgMQ6wEIMDAB#v=onepage&q=1930%20September%20Popular%20Mechanics&f=false
Answer I received: I can't say for sure but it appears to me that that the device is sort of "capacitor on a stick" kind of thing. When you touch the top to a power line it creates a potential on the copper tube inside that is the same voltage as the line. When it is withdrawn from the line then there is a spark as it pulls away and it loses potential.
There is always a little sparking when you are in an insulated bucket and touch a hot line with a metal tool like a wrench. It sparks because the tool goes from 0 volts to 7200 volts and sparks when you pull away. You can't see it in the daytime much but you can hear the crackle. Birds are able to land on a 7200 volt line and I'm sure they feel a tingle as there potential rises as well but not enough to make them fly away. However, you'll notice you never see birds roosting on a 69,000 or 131,00 volt line. They may try but as soon as their feet hit they feel a pretty good 'bite' and fly off. If they'd just hang on past the bite where they get the initial charge they probably be okay. However, I've been between 161,000 volt lines in a bucket and the hair on your arms and head will literally start to stand up.
It seems to me that a simpler way to deal with this question is to ground the line where you are working then there is no doubt. You hook a heavy jumper to a solid ground then take the other end and shield your eyes while 'slapping the hot wire' with the other end of the ground on a hot stick. If nothing happens you connect the ground to it. If you get a hot flash or are blinded you know it was hot.
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