Cutting a high-voltage power line. 43-second video:
https://www.youtube.com/watch?v=LuEpbXXq2NU
More: https://en.wikipedia.org/wiki/Spark_gap
Previously: https://www.homemadetools.net/forum/...3492#post78169
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Cutting a high-voltage power line. 43-second video:
https://www.youtube.com/watch?v=LuEpbXXq2NU
More: https://en.wikipedia.org/wiki/Spark_gap
Previously: https://www.homemadetools.net/forum/...3492#post78169
WTF! Cutting an energized line? What kind of electric utility endangers their employees by not switching the line out before they attempt something like that?
There are times cutting power isn't feasible. The other lineman holding it first is the SAFTEY ground and separator. As its cut free it will try to maintain its path till broken. Very high voltage can and will jump very long distances with differing weather . Bad stuff to mess with . That's why those giant towers , they hum extremely loudly kind of like a freight train down a track.
Yes Marv, WTF is exactly right. Impressive on one hand, ie the long ratchet cutter. But barely long enough, I note...Gives story 'arc' an all new meaning.
The yeehaw from the linesman indicates he expected something perhaps less electrifying...
I expect the common undertakings of utility companies isn't for the faint-of-heart, like hot-tapping natural gas lines. I just drove back from Reno, NV. On I-80 Eastbound, mile marker 207 to 231 or so, are an uncountable number of the large variety wind-driven generators. With prevailing weather, distance and other conditions in that part of Kansas, the next many miles were occupied with thoughts of 'how in hell' so much infrastructure gets in place.
thoughts of 'how in hell' so much infrastructure gets in place. One piece at a time.
Every week it seems that a complete wing generator passes through the town neatest where I live 3 trucks hauling the blades 1 hauling the turbine hub 1 hauling the Nacell ( the main body ) I don't know if the generator and all of the switch gear is inside or not, 1 truck hauling the top of the tower that has the swivel and 5 to 6 hauling the tower sections
""Wind power in Texas consists of many wind farms with a total installed nameplate capacity of 21,044 MW[1][2] from over 40 different projects. Texas produces the most wind power of any U.S. state.[3] Wind power accounted for 12.63% of the electricity generated in Texas in the 12 months ending Oct 2016.[1]""
какое отношение имеет данный видеоролик к Домашним Инструментам, это простои флуд.
My father worked for a major power company for many years as a substation operator. One of his frequently recurring jobs was to remotely operate the switches to remove power from a line before work was done on it. I never once heard him speak of working a line hot. In fact, he would tell stories about how fearful the crews were of unwittingly opening a hot line.Quote:
Originally Posted by Gary A. Wills
It's puzzling. The workers obviously know the line is hot, hence the stand-off cutter. Also, they've placed an insulating boot (red) on the nearby line. It could be there in case the cut line falls down on it or they're concerned about contacting it with the cherry picker.
I found a video which explains how and why they work this way.
https://www.youtube.com/watch?v=2IT6_ItjDbE
You guys might also be interested in this half million volt work
https://youtu.be/9Lbmis-VUW0
Reminds me of the recent super-hero culture. "Here, wear this magic suit and nothing will happen to you." Yeah, right. I guess I'm just too old. I'm from the era where you turn off the breaker before installing the new outlet.
Risking people's lives so a bunch of customers won't have their daily dose of "Judge Judy" interrupted just seems a bad trade-off.
Quote:
Originally Posted by Frank S
Agreed 100%, Frank S. Yet in the last 150 miles of my trip, after recalling what I've seen hauled overland in respect to the generator components, many other supporting actions came to mind. Excavators, graders, concrete and forms, cranes, rigging, all those operators, electricians and who knows how many other labor contributions...When these generators were first prototyped, the blades were spar-milled a lot like spars of aircraft wings. Few were made, realizing power consumed to do so, delayed offset of coal fired electric power. Hand laid fiberglass was next, I believe also first large scale use of carbon-fiber materials shortly thereafter.
When I taught middle and high school STEM presentations, tying facets of STEM together around manufacturing, we would list as many operations they could conceive needed to produce and market an item; shoes, inkpen, cell phone, ream of paper, breakfast cereal, whatever they chose to unravel. It would run through the entire day, concurrent with other discussions, where Science, Technology, Engineering, (or) Math were covered. So, would end up with dozens of considerations in their "all-encompassing" itemization. As facilitators we'd offer those too, but not in excess detail, just to trigger another flurry of 'what about' this or that.
Somewhere, not too close to days end, I'd field something like "There just can't be anything else?" "Right?" Often they emit sighs of relief or NO WAY! at that.
A favorite comeback of mine was "...so didn't someone make paint spraying equipment, for enough wheels of an entire fleet of delivery trucks...". The NO WAY became even louder.
Few things mean more to me, than being a cog in this machine we know as "Manufacturing".
And I'll side with Marv; Judge Judy doesn't warrant the risk to high-voltage wire men; but at the same time USA is a gold-medalist when it comes to certain utilities and respective codes, especially NEC, UPC, & NFPA.
If it were just a matter of Susie homemaker missing Judge Judy or Tommy couch potato missing a re run of the family guy I would have to agree with Marv However we all know that life is much more involved than that to shut down the line might have effected several thousand small and large business putting countless number of workers out of work for who knows how long this would also have probably effected many Emergency service facilities as well as critical life care facilities, Financial corporations communications operations and the list goes on and on and on.
Killing a high voltage power line by opening the contacts at a power station or substation does not imeadiatly kill the line virtually everything down-line becomes potentially a capacitor or a back feed generator for a while which means not only does the switch need to be opened but the line must be de-energized and subsequently Earthed to ground for the period of the repairs being made. Replacing old power lines with new ones is even more involved as the new line will become energized just laying on the ground with static electricity.
My hat is off to the guys who have to work in these environments As a young-ling for a while I worked at a company which designed and manufactured high tension stringing equipment. One of my later business partners actually held several patents for some of that machinery but he also had patents on a design for 20 ft diameter a hydraulic motor which was being developed to rotate the turret of the big guns in battle ships of which only the prototype was ever made due to the era of the ending of the requirement to build another battle ship but that is another story.
If the line is cut somebody will lose power.
Now I want to to see how the reconnect the "live" wire!!
I will not be surprised if they cut the power.
Ralph
Like Marv said about his father having to switch power at a substation to kill lines in certain areas while leaving others live. This would be by far the preferred method.
Since we have no way of knowing where the line terminated on the other end I will make a summation that the main line probably fed a metropolitan area and the branch line they cut possibly went to a substation which for all we know may have been in the path or at risk of being overtaken by a wild fire or possibly sustained damage due to a storm. We can only hazard a guess, but it is clear to me that there must have been a load on it somewhere down stream they were unable to clear otherwise there would have been very little to no arc when the line was cut
Mylar ballon + power line = internet sensation. This is available as a GIF too, but then you don't get the awesome sound. 21-second video:
https://www.youtube.com/watch?v=zqFm52C1n5Q
17-second video. You can hear the branch screaming as its steaming:
https://www.youtube.com/watch?v=g4ph-h7l_aM
Downed power line on swingset.
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Good thing no one is leaning on the fence.
I personally think the fireman is standing a bit to oclose to the fence. Those rubber boots do have a voltage breakdown point I am sure. That is a primary line of several thousands of volts. If it was a secondary line it would have popped a fuse on the transformer.
wouldn't want to pay the electric bill for that one
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What am I missing here? the guy has hold of the end of a downed high tension power line which is obviously still energized as evidence when it hits the ground, yet it was not showing any arcing while hung on the metal street lamp pole.
Frank, I was bothered by this as well. I looked for a link, but only found the news story that had the police officer interviewed. But It lacks any technical explanation (TV news media source). I'm believing this was a low tension line, appears to have insulation, and somehow a high voltage short contacted it right at the same time it hit the ground. But even that seems remote in probability.
There clearly is something else going on that is not being told.
What draws my suspicious nature; that sky looks early evening when the rain suit guy whips the loose end. Then, suddenly it's dark. No flaring from overexposure, it's uniform.
This really did occur. I watched it Tuesday morning on ABC news.
This was taken from a police car dash camera. Manchester New Jersey.
The camera exposure is affected by the brightness of the arc flash.
https://www.youtube.com/watch?v=jHW_R4xCM_Q
Ok I think I saw a transformer flash a couple of times You are probably right it did look insulated at least if the black color had anything to do with it. If it broke from the secondary side of the transformer it would only have been energized by being back fed from where ever it went to down line. The transformer could have had dozens or shorted coils inside and possibly instead of sending 120 or to 240 single line voltage it may have sent a couple 1000 colts to the switchgear panel or what ever it was connected to. and being shorted the fuses may not have blown for some reason or they could have charred and not fell out of connection. it might not have been until the fault reached the substation that the power finally went off.Quote:
Originally Posted by metric_taper
Electricity can be funny in the way it finds away, almost as if it has a self preservation to life at times.
A line man showed me some pictures of a pair of 35/50 transformers sharing a pole with another pair, both had their tops blown completely off yet somehow the secondary's were still energized for a while.
Also the news story on CBS said the worker was wearing insulated boots gloves and insulated suit, that was not rain gear.
Ralph
I wonder if his underwear was insulated. I know if that had happened to me I would have filled mine up......
It is strange that he just grabbed the cable with his hand usually they use a pole.
The news report also said they would be a review if all standard practices were followed.
Apparently some announced the line was dead, even the cop had been told it was dead.
Ralph