If one is experienced in high voltage stuff professionally one does not have any of such equipment at home nor does one go in the direction of such devices if not strictly necessary. Knowledge of the possible results of slight human errors are enough to keep clear. I have seen some DIY tube amplifiers with high voltages combined with definitely lethal possible currents, no PE, shielding or safety and built so so in homes with pets and children. All too often such a builder brags about having 2.5 kV in a device where an experienced tech will shake his head.
A tech here survived 10 kV from a very old open switch that was supposed to be deenergized and checked by the person in charge. As he is the cautious type (helps surviving ones job) he insisted on wearing safety boots, a mat and he used a plastic ladder besides all the usual PPMs like a mask and insulating gloves. When acting like that one gets ridiculed by fellow techs (sissy, too cautious etc.). Long story short: he survived a jolt with only a burn wound and 1 day kidney trouble. All limbs are still there which is very unusual for 10 kV incidents.
People working in energy distribution use the expression kilovolt or kV. Not KV or kv. Current in ampère or A, mA, kA etc. Sloppiness in expressing oneself can translate to being sloppy in other areas as well.
A tech here survived 10 kV from a very old open switch that was supposed to be deenergized and checked by the person in charge. As he is the cautious type (helps surviving ones job) he insisted on wearing safety boots, a mat and he used a plastic ladder besides all the usual PPMs like a mask and insulating gloves. When acting like that one gets ridiculed by fellow techs (sissy, too cautious etc.). Long story short: he survived a jolt with only a burn wound and 1 day kidney trouble. All limbs are still there which is very unusual for 10 kV incidents.
People working in energy distribution use the expression kilovolt or kV. Not KV or kv. Current in ampère or A, mA, kA etc. Sloppiness in expressing oneself can translate to being sloppy in other areas as well.
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Opcom, I read through that linked thread but the event mechanism was a little unclear to me. One description was that he was clear of any HV, and was just repositioning an internal cable - albeit blindly with one hand. There was a photo of an in-line Millen connector, mated to a chassis socket, with a HV wire with red insulation that was supposedly feeding into the Millen connector, but had been somewhat wrenched out of the connector, and skin on the metal outer of the Millen connector.
I guess my main query is if he had unintentionally started to reposition the HV wire with red insulation, rather than another internal wire !? The red wire didn't appear to be close to any other internal wiring or plugs, but there were only one or two photos to look at.
It's not fair to make judgement without a good awareness of the situation, but some of the description indicates a lack of preparedness, let alone risk assessment and adequate mitigation.
Some of the thread discussion went on to HV coax, where I guess that provided at least an extra layer of protection if the braid was adequately grounded. To me, that implied he accidentally grabbed the red insulation of the HV wire, and leakage was sufficient in that grab location for conduction, although the Millen plug outer was likely grounded, or was he disconnecting that plug?
It's a salient point for all that if you don't need to adjust/move/etc anything in a live area of circuitry, then don't. And if you do, then assess and mitigate, as that forces you to think about all the things that could accidentally happen.
I guess my main query is if he had unintentionally started to reposition the HV wire with red insulation, rather than another internal wire !? The red wire didn't appear to be close to any other internal wiring or plugs, but there were only one or two photos to look at.
It's not fair to make judgement without a good awareness of the situation, but some of the description indicates a lack of preparedness, let alone risk assessment and adequate mitigation.
Some of the thread discussion went on to HV coax, where I guess that provided at least an extra layer of protection if the braid was adequately grounded. To me, that implied he accidentally grabbed the red insulation of the HV wire, and leakage was sufficient in that grab location for conduction, although the Millen plug outer was likely grounded, or was he disconnecting that plug?
It's a salient point for all that if you don't need to adjust/move/etc anything in a live area of circuitry, then don't. And if you do, then assess and mitigate, as that forces you to think about all the things that could accidentally happen.
Long time ago (~2010), one colleague arrived crying in the work. People asked what going on, and he replied: one friend of mine died yesterday. He are making maintenance of some ~6kV high power industrial equipment, and something goes wrong (no explanation if it was operator error or catastrophic equipment behaviour). Anyway, this always makes me to remember to untrust others and equipment when high voltages or dangers are present. Even lower voltages, if are present at dangerous places.
Routine and getting used to dangerous situations (leading to overselfconfidence) both can be lethal.
The old saying "familiarity breeds contempt". Some get away with mistakes and shocks everytime, but I wonder for how much longer with that escape tactic until the big one comes ? Simply, the old rescue adage of the glass TV era of never let one´s body complete the cardiac electrical circuit....by toughing two electrical parts on a chassis. A tube amp isn´t a difbiliator.
I´ve seen and come across some dreadful electrical accidents in my time, some others created by an over enthusiastic user approach and others from sheer ignorance. Walking through a utility substation with 400kV buzzing around with an odd flash-over from a long transformer insulator is an eerie threatening feeling. I don´t like it.
Bench Baron
I´ve seen and come across some dreadful electrical accidents in my time, some others created by an over enthusiastic user approach and others from sheer ignorance. Walking through a utility substation with 400kV buzzing around with an odd flash-over from a long transformer insulator is an eerie threatening feeling. I don´t like it.
Bench Baron
Was once in a 400 kV substation on a warm humid day and being electrosensitive normally is a good thing. Here it turned to fear. I felt the current of the field strength going through arms and feet while walking.
I was scared. Worse: fear from what I like.
I was scared. Worse: fear from what I like.
Some time ago my wife and I are cycling in a avenue that are crossed by 4x 500kV power lines, in a very dry and windy day. The bikes are making shocks/little sparks to us... We need to not touch in anything with metal in the bike. This with cycling normally... after crossing the lines, the shocks stopped.
I just work in a place where these lines originate (the Itaipu DAM, touristic famous here)... safety first always.
I can't comment on what more there may be to the story since I was not there, and the account is all there is available.
I got the living $#1+ shocked out of me lighting up fluorescent tubes up under 500kV lines. It gets brighter if you hold it wayyyy up in the air like this…. EEEYOWCH!!!!!
Hehe. BTW, my history needs a disclaimer: that the sparks are only tactile (very small), and invisible in the sunny day. And very short; only when almost touching the bike metal parts, are feel. For our luck...
Like the ones when we touch a car with cold dry climate.
The humidity can be under 14% these day, but is hot sunny day.
Now, why a line with nominal AC current are boosting electrostatic discharges, I dunno... but makes one remind about electricity and its effects.
Like the ones when we touch a car with cold dry climate.
The humidity can be under 14% these day, but is hot sunny day.
Now, why a line with nominal AC current are boosting electrostatic discharges, I dunno... but makes one remind about electricity and its effects.
There is no such thing as 14% humidity here. Back in Florida (where I got that particular zap) it’s rarely below 94%. You go out and listen at night and it sounds like bacon frying.
440V breaker cabinets are notorious for blowing up and enveloping some poor unfortunate in plasma from head to foot. One unfortunate tangled with a 2.3 kV motor starter cabinet by ignoring 3 basic safety directives and got death for his mistakes.
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I worked on an argon fluoride ultraviolet laser (193 nM, deep UV indeed) during a short stint in grad school at Cornell. My professor wanted a UV sledgehammer for knocking molecules apart. The laser was driven by a 25kV Universal Voltronics power supply, with the transformer and multiplier inside a 55 gallon drum filled with transformer oil. The inside of the laser box was lined with mylar sheet for insulation, which would absorb a monolayer of moisture during the humid Ithaca summers. As I would ease up the variac on the power supply control box, the laser would make a noise like a pan full of frying bacon, and my constant mantra was "please don't arc, please don't arc". Any arc would cause the supply to immediately shut down, as it was well-protected.
Low voltage high current installations are (here) statistically higher risk areas indeed. High voltage was a regulated strictly long ago as there were too many accidents. Since then working in high voltage needs special licenses, education and certifications so there are less people qualified. The way installations were built was also strictly regulated. The very old open installations are rarities which no one really likes.
This makes HV installations/rooms arguable safer working environments. Because of the high accident/severe consequences number the working procedures are hammered in ones head and one needs to refresh licenses every 3 years. No license no job. High(er) voltage DC is a special category.
Still one knows what happens when one makes a mistake.
This makes HV installations/rooms arguable safer working environments. Because of the high accident/severe consequences number the working procedures are hammered in ones head and one needs to refresh licenses every 3 years. No license no job. High(er) voltage DC is a special category.
Still one knows what happens when one makes a mistake.
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Interesting, some of these phenomenon are helped with humidity, and others not, I suppose... (the static electricity obviously helped by low humidity)
Yes, these insulators are audibly noisy at days with high humidity, even some ones from 13.8kV and 34kV "medium voltage" urban lines... BTW, humidity here varies a lot within the year and climate (here dries with La Niña, and rains like crazy with El Niño, so can varies from ~12% (but is rare to drop below 26%) to basically 100% from seasons.
It's a good thing I don't work in energy distribution. I would hate to be sloppy in my life or work. In electronics, all kinds of written communication and books where I live, KV is as common as kV because it's an acronym, and no snoots up about it.
You may be surprised at how many people routinely use 2-5KV at home, in gear they buy or build. Those include a subset of broadcast equipment engineers where the voltage runs up to 20-30 KV in TV transmitters which they maintain, who are also ham radio operators. In energy distribution, acording to the International Electrotechnical Commission, high voltage begins at 36KV, so even if citing these persons for their home hobby work, it would not apply to the voltages they use, except rather sloppily.
The lack of a direct description of what happened is what amazes me in that 'account', especially as many experienced people were commenting. Perhaps many posters didn't want to expose what actions the guy made, and rather would discuss other types of cables and plugs as being safer. Given the near death experience being exposed on a public forum, I would have thought it just as important to present an 'incident report' and to clearly identify root cause and mitigating measures.