MasterBlaster
Administrator Emeritus
I wonder why it didn't trip the fuse in the transformer?
Sometimes they take 2 or 3 zaps before blowing.
Sometimes they take 2 or 3 zaps before blowing.
Powerlines
- Thread starter MrPopper
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ValleyArborist
TreeHouser
I was patrolling a 500 kV line this past fall, and i cut a cherry sapling that had about 30 ft of clearance from tips to conductors. I cut it with a handsaw and pushed it over and it nailed me. Hurt the rest of day. Those EHV lines are a lesson in just how powerful electricity is, you dont have to be anywhere near making contact to get a shock.
Raj
TreeHouser
I dunno, 1000 amp transformer arcing aluminum wire which would be may be about 200 Amps, it burnt for about half an hour.
Jed
TreeHouser
ValleyArborist
TreeHouser
I've parked under them and have been shocked getting into my toolbox or opening the door, of course after a while you learn, don't park under them.......
Basically everything from 230 to 765 kV will do it.
Basically everything from 230 to 765 kV will do it.
Taking the top off a pine well outside the "safe distance" of 365kv lines once and got lit up good.
All was fine until the hinge popped loose...current came through saw/hands and held me to the tree shaking with saw running full blast until the top fell away, then let me loose. Not an overly muggy day, top fell parallel or lightly away from lines.
Didn't feel real great for a couple hours, but still kickin' and no burns.
All was fine until the hinge popped loose...current came through saw/hands and held me to the tree shaking with saw running full blast until the top fell away, then let me loose. Not an overly muggy day, top fell parallel or lightly away from lines.
Didn't feel real great for a couple hours, but still kickin' and no burns.
ValleyArborist
TreeHouser
Some of the older EHV lines, ones built in the 60s and 70s, the engineering isnt always so great, especially in parts of the world with hilly geography. been in spans where the ground to conductor height was so low that grass was incompatible vegetation. (Seriously). I always get a nauseous feeling that close, the energy is just too much i guess.
My lekky lightjolt was in Bermuda, I think the primaries are 14,000, I' not entirely sure, just the barest tippy-tip of the green branch brushed it, momentum kept it going, if my hands and wrists ached for half an hr with just that I hate to know any worse!
I turn down all work within 10' of energised sources now, or the HO has to get the current turned off. Last one was a removal, the lekky light guys came and took the whole wire down, sure knew it was safe then!
I turn down all work within 10' of energised sources now, or the HO has to get the current turned off. Last one was a removal, the lekky light guys came and took the whole wire down, sure knew it was safe then!
MasterBlaster
Administrator Emeritus
I've never seen it jump 30 feet before.
I didn't see anything Butch, just felt it.
VA, I know that nauseous feeling. I've seen some lines hanging pretty low enough in the summer to start burning the young trees under them. One of the scariest jobs I did was removing trees that weren't burnt yet in that area...had to do about 3 spans worth...think I prayed through the entire job.
VA, I know that nauseous feeling. I've seen some lines hanging pretty low enough in the summer to start burning the young trees under them. One of the scariest jobs I did was removing trees that weren't burnt yet in that area...had to do about 3 spans worth...think I prayed through the entire job.
ValleyArborist
TreeHouser
Not a visible arc, it's like static buildup, induced voltage I guess would be the term. Half a million volts makes some strange physics
MasterBlaster
Administrator Emeritus
I was referring to this post.
ValleyArborist
TreeHouser
Thats what I'm saying, the electromagnetic field around the conductors, you can actually hear them humming
MasterBlaster
Administrator Emeritus
Oh, I've heard that - even felt it, sorta... the hairs on the back of my neck...
ValleyArborist
TreeHouser
savvy farmers know that it can electrify fences, eliminating need for an expensive fence charger. I always take an insulated Jameson walking stick with me to push down on fences to cross them when im out on patrol.
Merle Nelson
TreeHouser
My brother was an electrical engineer for Sierra Pacific Power Co. in Nevada. He used to drive across the state to visit family. On this long trek he saw a cabin all lit up bright out in one spot time and again at night. He knew that no power was delivered to any individual out in that area it was just big transmission lines taking it across the state.
Unfortunatly for this particular old timer my brother likes to solve problems posed to his mind. So he figures the guy is tapping into the transmission lines in some way and stealing power. They go out there to find out how he is doing it and it turns out the guy built a fence right under the power lines and running along for some distance. Accept instead of stringing it with barb wire or something he strings it with copper wire. He had to pay the power co. for a whole bunch of back power usage.
Unfortunatly for this particular old timer my brother likes to solve problems posed to his mind. So he figures the guy is tapping into the transmission lines in some way and stealing power. They go out there to find out how he is doing it and it turns out the guy built a fence right under the power lines and running along for some distance. Accept instead of stringing it with barb wire or something he strings it with copper wire. He had to pay the power co. for a whole bunch of back power usage.
Limbrat
TreeHouser
It is induction. An isolated, supposedly dead line running parallel to an energized one will pick up free electrons and become energized, a battery of sorts. A transformer works on induction. There is no connection between the primary and secondary windings in a transformer. As far as the line arcing to ground, the distance is relatively small but of course increases as the voltage increases. Once an arc is created however, that arc can follow whatever object that is creating the path to ground for a much greater distance because now the air in the arc itself is being ionized and becomes a conductor.
FireFighterZero
Captain Zero!
So are the primary and secondary number of turns backwards for a transformer than say an automotive ignition coil?
Raj
TreeHouser
More turns for the higher voltage.
SouthSoundTree-
TreeHouser
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Good video.
Makes me happy that we don't have to work around power lines here.
Except for the real biggies 380 Kv upwards.
Everything else has been put underground since the -99 storm took out the power to most homes in the country for up to a week in winter.
I don't miss the old pre 99 days, to tell you the truth.
Makes me happy that we don't have to work around power lines here.
Except for the real biggies 380 Kv upwards.
Everything else has been put underground since the -99 storm took out the power to most homes in the country for up to a week in winter.
I don't miss the old pre 99 days, to tell you the truth.
