Re: Danger, Danger Power Lines!
I do climb a tree in my backyard that is right next to and below two power lines plus TV cable lines.
The down service line to my house is actually two cables (insulated wrapped together in a bundle plus the ground wire that is exposed.) I have cleaned branches near or close to that one line and I am fairly safe while trimming stuff around there.
I wanted to respond to that and almost forgot. I have no problem whatsoever with that. By saying that I am not approving climbing near all lines in all trees, but the lines you are talking about are 240 volt, insulated lines. I'll bet the insulated lines are loosely wound around a bare line. That's the ground line. Hence the 240, actually only 120 V with respect to the ground line, are in contact with the ground wire. It would really be exciting if the 'hot' lines weren't insulated.
...Now Above and in top of the corner pole is the 250volt (I don't know the capacity of the three primary lines (10 to 15KW)but it is strong enough to handle the entire line of houses down the street and every two or three poles there is a transformer so that one is above my tree and I try to stay the heck away from those lines BUT ( there is always a BUT) once I send the throw line over two of those lines and I was very concerned about retrieving that line - No indication of any of burning or sparking but I am sure that the potential for electrocution was there present under the right moisture and conductivity of the material and from experience growing up with my family owning an electrical power plant where we could see how much damage a live wire can do in milliseconds - It does not take much time to kill a person or at least give it a good burn.
I doubt it. With clean dry throwline, even reasonably clean throwline, throwline it is an excellent insulator - much better than air. I've had the same thing happen on probably 44,000 volt lines and absolutely nothing happened; not between the phases, not from phase to ground, nothing. That's because the throwline is a much better insulator than air.
But, having said that, I am in no way saying that's a safe thing to do. It is always very bad and dangerous to let anything come too close to or in contact with high voltage lines.