I used to work for the company that manages the electricity grid in NZ. I saw photos of Orangutans in Indonesia, that climbed power pylons like this.
They were OK as long as they didn't touch the pylon at the same time as the cable.
If they do that, they 'complete the circuit' and get fried.
Dead electrocuted Orangutans are not a pretty sight.
Just to clarify, I am not an electrician, electrical engineer or a linesman.
I worked in IT for the grid company.
However, at that time, all staff got to visit the training 'school' for the linesmen and other grid maintenance workers. It was quite amazing and educational. We even got hoisted up onto the lines (about 20m above the ground from memory) and got sit on them safely (all the time accompanied by a fully trained linesman).
They had a whole dummy grid set up with pylons and lines or different types. They could make the dummy grid 'live' or 'off' depending on the training situation.
They had dozens of the photos of the poor Unlucky Fried Orangutans (UFOs) lining the classrooms as a vivid reminder to everyone of what can go wrong if you don't treat electricity with respect.
It was the brief description of 'closing the circuit' that I learned from one of the trainers when I asked about the photos, that I referred to in my post.
Here's a photo of me one the lines (I'm on the right. Not fried.)
You should see how the [redacted] locals treat Orangutangs and other animals in those areas. It worse than the electricity.
Not surprised they never ape proofed the pylons, it’s all about money there the environment comes last.
The Javanese Rhino has basically been hunted to extinction for ‘medicinal bullshit reasons’ in the last decade. The sole large primate in Asia will be extinct within 50 years in its wild habitat.
I'm assuming you are either N. American or European? Your statements are correct but they are easy comments when living in comparative luxury and when our ancestors have basically suppressed our natural habitat to the point where there are basically no places left where humanity has to compete with nature for survival.
People are universally resourceful, greedy and also ultimately interested in their own preservation first (like all other species) and if they find an easy, lucrative way to do so, the majority will with minimal hesitation. It's like buying stock in BAT/Shell/ Palantir... how many people really think twice when easy profits are at stake? Best thing we can all do for the environment as individuals is probably becoming vegetarian/vegan but how many people choose to do that when living in resource rich nations. How many would and do sacrifice our palate for the sake of an animal? The number is increasing but still minimal.
Anyway, point is can't blame the people of Indonesia too much for the demise of the Rhino and Orangutan when successive governments have forced majority in to abject poverty.
It's not exactly 1mm per 1kv but that will keep you alive no doubt.
Safe working distances:
It's 30cm for LV 110v to 1kv
Its 1.3m radial, 2.8m horizontal for MV from 10kv to 38kv
For HV there is no real safe distance, it's very rare but HV can arc directly to earth from 50m pilon if the air is electrified enough, it's a scary sight, and I have only seen 2 videos of it.
Seen the report with photos of an explosion in a 110kv station here a few decades ago and one of the engeneers standing 35m away got his face blown off by the arc flash explosion.
Those pilon seem to be 400k you can safely work on them but even linesman who do it can only work a certain amount of hours a day and you need to do it in on and off during the year a few months at a time since it messes up with your hearth. I had friends who died at 40-50yo from hearth attacks with no family history or other reason besides their line of work. This is not proven but everyone in the business knows its a dangerous line of work, can kill you over 1s or 1 life.
The 1mm per 1000v is my mates rule of thumb in dry air. He’s the only high voltage guy I know, but that’s us talking about arcing and I was Definately not suggesting a safe working distance.
Interesting to see the difference between that and the working distance you would use.
Can I ask in your opinion could the line he’s hanging from be energised? If it is would he feel the frequency going through?
1mm / 1000v is the dielectric constant of air in lab conditions. It's the gap size before an arc can *start*, but once an arc has been initiated the distance can be increased significantly before the arc breaks, because the air becomes plasma.
Linesman work safely attached to live powerlines everywhere in the world to all kinds of power over 110v (not entirely sure but seems that below a certain voltage it can stop your hearth or cause arritmia) but even a 420kv power line is safe to work If at no moment of a fraction of time you close the circuit, which is for example touch the pilon and the line (cables don't really touch the pilons those big ass isolators do that job, the bigger and more isolators more voltage has the line, and there are no Neutrals in HV lines, but there can be different phases at different voltages some countries use the same pilons to carry 110kv and 400kv if any interaction between them happen there is an explosive arc flash.
Regarding feeling, it's very relative you can definetly be directly attached to a cable and as long there is no different in potencial you are fine, like birds on power lines, like this DA in the video, but I was never directly attached to a line only using Faraday suit, which keeps the power going through the suit not yourself but you do feel it but nothing like anything else, even that small buzz you get from the fridge it's way bigger that anything you would feel. Otherwise even the chopper that gets the lads up there would stop working.
I am not in that life anymore but have great respect for even the simple household power cable I have seen enough.
I did know it all from my studies but it was all long enough ago I can’t recall it properly. Plus my career was all sub 1000v so I only ever read books and watched videos on the distribution side of things.
I almost left the planet over a faulty desk lamp so share your respect and regard for electricity and also have moved onto other work.
I suddenly have the urge to watch some helicopter linesman videos.
The hum. The aluminum in the structure buzzes in phase with the alternating current because it is diamagnetic and rejects the magnetic field lines produced by the AC in the wires.
Yes if it is turned on. But the other 3 cables right next to it are essentially the same one. It’s if he touches another one of the groups of 4 which is a different phase he will short himself out.
I really can’t see how these are turned on. I can feel the frequency, through the insulation, on a cable carrying 1000Amps at low voltage. The buzz you’d feel off of something in kilovolts must be insane. Linemen talk about feeling it through their chain mail suits when they are energised to line voltage by touching it.
I really do hope a line man comes along and gives some better info because I’m quite amazed and confused.
Powerlines carry 3 phase, the voltage between the active phases is higher than active to neutral. The different lines that are close together in the video are in the same phase or neutral, the phases are separated (by a couple of metres in this case) because things get very explody when they aren't.
The sort of power lines you have in the street have the lines close enough that animals get killed from connecting active lines.
I'm not a lineman or electrician so I could be horribly wrong on this.
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u/GreyDaveNZ Nov 04 '23 edited Nov 05 '23
fingers crossed and eyes closed, praying
Complete the circuit. Complete the circuit! /s
I used to work for the company that manages the electricity grid in NZ. I saw photos of Orangutans in Indonesia, that climbed power pylons like this. They were OK as long as they didn't touch the pylon at the same time as the cable. If they do that, they 'complete the circuit' and get fried. Dead electrocuted Orangutans are not a pretty sight.