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Three-Phase posted:Anything we have over 4160V uses VPI, where you take the windings and put them in a vacuum tank to suck all the air out and replace it with some kind of varnish or epoxy or whatever. I think it was class H insulation for a 185 degree C rise. I think there's also this extra layer of black "corona tape" that I saw these guys using for motors or generators above 4160V. yeah we get that sort of job here and there. I hadn't worked on a vpi yet but I heard they get crazy amounts of insulation, like 8+ layers. The corona is a bitch, it rubs off everywhere and will ruin a coil if you don't clean it out of your stands.
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Nov 30, 2015 02:11
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kalstrams posted:Yes, 4th degree burn can imply up to (?down to?) necrosis of even bones. 
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Nov 30, 2015 02:53
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What is this and when is it going to burn down the building it's in or kill someone? 
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Nov 30, 2015 13:12
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Air-cooled transformer 
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Nov 30, 2015 13:16
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Cheez posted:What is this and when is it going to burn down the building it's in or kill someone? It's an AC transformer... I have no idea what the gently caress it's doing there... step-down for a 12v something? Shouldn't that be in a junction box?
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Nov 30, 2015 13:51
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GnarlyCharlie4u posted:It's an AC transformer... Doorbell?
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Nov 30, 2015 13:55
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spog posted:Doorbell? Ding-dong! I think we have a winner!
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Nov 30, 2015 14:06
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Gorilla Salad posted:From the schadenfreude thread, one of the most hair raising videos I've ever seen. I feel a hell of a lot more confident in my fall harness, now. Holy poo poo.
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Nov 30, 2015 14:26
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GnarlyCharlie4u posted:It's an AC transformer... The doorbell transformer itself is fine where it is, but the wire nuts should be in a junction box.
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Nov 30, 2015 17:22
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Cat Hatter posted:The doorbell transformer itself is fine where it is, but the wire nuts should be in a junction box. Not really. It's made so the threaded nipple can be inserted through the wall of the box and have a conduit nut installed to hold it in place. The exposed 120 volt conductors are a no-no. That's not to say there aren't literally millions of these installed around the country like in the picture.
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Nov 30, 2015 17:24
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ncumbered_by_idgits posted:Not really. It's made so the threaded nipple can be inserted through the wall of the box and have a conduit nut installed to hold it in place. The exposed 120 volt conductors are a no-no. That's not to say there aren't literally millions of these installed around the country like in the picture. I'm just saying that the transformer itself doesn't need to be in a box, only the nipple that would go through a knockout in a junction box. That being said, I'm wondering why it has ears for mounting on a stud in the first place. Sure it would add stability, but the transformer isn't very heavy and should be secure enough just attached to the junction box.
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Nov 30, 2015 17:39
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Cat Hatter posted:I'm just saying that the transformer itself doesn't need to be in a box, only the nipple that would go through a knockout in a junction box. That being said, I'm wondering why it has ears for mounting on a stud in the first place. Sure it would add stability, but the transformer isn't very heavy and should be secure enough just attached to the junction box. We use similar transformers in our control panels at work, when needed. You can just secure them directly to a panel box chassis or just the side of the box itself.
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Nov 30, 2015 17:46
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Sagebrush posted:I really hope that the blue glow is because he's holding up some kind of phosphorescent paper, and not because he's created an x-ray machine powerful enough to produce a visible image without any kind of sensitized detector The blue glow isn't Cherenkov radiation like Xerxes17 said, but is probably just x-ray fluorescence. This is easiest to understand when compared with UV fluorescent--when you put white paper under a blacklight, electrons in some of the molecules present will be excited to higher-energy states, and will emit photons when they relax back to their ground states. However, when x-rays illuminate paper, they can have enough energy to cause electrons to be freed from molecules. If an inner shell electron is ejected, a higher-energy outer shell electron will take its place, causing a photon to be emitted (like with UV fluorescence) to make up the energy difference between the states. (i am bad at explaining physics)
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Nov 30, 2015 19:42
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So what you're saying is a wizard did it.
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Nov 30, 2015 20:04
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Slanderer posted:The blue glow isn't Cherenkov radiation like Xerxes17 said, but is probably just x-ray fluorescence. This is easiest to understand when compared with UV fluorescent--when you put white paper under a blacklight, electrons in some of the molecules present will be excited to higher-energy states, and will emit photons when they relax back to their ground states. However, when x-rays illuminate paper, they can have enough energy to cause electrons to be freed from molecules. If an inner shell electron is ejected, a higher-energy outer shell electron will take its place, causing a photon to be emitted (like with UV fluorescence) to make up the energy difference between the states. You mean as caused by an optical brightener, right? That is, untreated paper (like U.S. banknotes) wouldn’t have glowed.
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Nov 30, 2015 20:21
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Platystemon posted:You mean as caused by an optical brightener, right? Interesting. I am curious though if that has something to do with U.S. currency being linen based (not that I can think of any reason wood would glow better) and if regular bleached paper would/wouldn't glow under a black-light.
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Nov 30, 2015 20:35
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Platystemon posted:You mean as caused by an optical brightener, right? That's correct. Basically all white paper will use an optical brightener so that they don't look yellowish. US bills won't fluoresce much since they're printed on cotton, but they do have a fluorescent strip for detecting counterfeits. Modern laundry detergents have fluorescent whiteners too. Teeth whiteners also work the same way. However, even untreated paper can still fluoresce, just probably not noticeably (but detectable with spectroscopy). I think some plastics will fluoresce naturally, but lots of plastic (or silicone, or any other moldable polymer) components in modern stuff use fluorescent coloring to make them stand out more (which is effective, but only accelerates color changes from prolonged UV light exposure).
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Nov 30, 2015 20:45
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I'm staggered that someone can be smart enough to construct a power supply for one of these tubes (it's a non-trivial exercise), but completely oblivious to the obvious danger. Jesus.
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Nov 30, 2015 20:47
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Cat Hatter posted:Interesting. I am curious though if that has something to do with U.S. currency being linen based (not that I can think of any reason wood would glow better) and if regular bleached paper would/wouldn't glow under a black-light. You'll be hard-pressed to find modern white paper without it. However, try it on an old library book, or maybe the paper in a drug-store romance paperback.
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Nov 30, 2015 20:47
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Cheez posted:What is this and when is it going to burn down the building it's in or kill someone? I think I can out do you pretty easily with my doorbell transformer - tapped into knob-and-tube wiring (yes, still in use) Just to ice the cake - I'm pretty sure it's mounted to a square of asbestos. 
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Nov 30, 2015 21:03
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Slanderer posted:You'll be hard-pressed to find modern white paper without it. However, try it on an old library book, or maybe the paper in a drug-store romance paperback. Try a check/cheque book.
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Nov 30, 2015 22:16
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Ponderous Saxon posted:I'm staggered that someone can be smart enough to construct a power supply for one of these tubes (it's a non-trivial exercise), but completely oblivious to the obvious danger. Jesus. I'm pretty sure it has to be the combination of combining just enough knowledge to be dangerous with living with a low life expectancy and lack of opportunities. You kind of have to up the ante for thrill seeking to even begin to feel like you're living on the edge. Like in the US, kids just read Erowid and trip off research chemicals they ordered over the internet. Russian kids do Krokodil. That's a pretty good example, I think. Edmund Sparkler fucked around with this message at 23:14 on Nov 30, 2015 |
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Nov 30, 2015 22:51
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Looks like its about to explode... actually i think its fine... actually nope gonna explode. https://www.youtube.com/watch?v=osy2cGfmEAQ
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Nov 30, 2015 23:01
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Applebee123 posted:Looks like its about to explode... actually i think its fine... actually nope gonna explode. What the hell
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Nov 30, 2015 23:34
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Applebee123 posted:Looks like its about to explode... actually i think its fine... actually nope gonna explode. I've had a girl do that to me once.
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Nov 30, 2015 23:37
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ReagaNOMNOMicks posted:I've had a girl do that to me once. Gotta watch those liquid metal girls. 
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Dec 1, 2015 00:31
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-Zydeco- posted:Crosspost from the Russia Thread I felt unsafe just watching that. Wasn't helped by the fact that I could hear other people in the house
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Dec 1, 2015 03:35
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 Chainsawing on the forklift in Korea.
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Dec 1, 2015 07:19
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I was on vacation in NYC this past week and I was walking back to the hotel after lunch on Thanksgiving, when a ton of sections of streets and avenues are closed to traffic for construction of poo poo like holiday markets. One of the traffic signals was opened up at the ground, and the wiring they had pulled out of the post caught my eye. I'm not an electrician, so how does this look?
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Dec 1, 2015 08:05
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chitoryu12 posted:I was on vacation in NYC this past week and I was walking back to the hotel after lunch on Thanksgiving, when a ton of sections of streets and avenues are closed to traffic for construction of poo poo like holiday markets. One of the traffic signals was opened up at the ground, and the wiring they had pulled out of the post caught my eye. I'm not an electrician, so how does this look? Looks right to me. I did traffic signal installation and maintenance a few years ago.
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Dec 1, 2015 08:55
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chitoryu12 posted:I was on vacation in NYC this past week and I was walking back to the hotel after lunch on Thanksgiving, when a ton of sections of streets and avenues are closed to traffic for construction of poo poo like holiday markets. One of the traffic signals was opened up at the ground, and the wiring they had pulled out of the post caught my eye. I'm not an electrician, so how does this look? Reminds me of this https://www.youtube.com/watch?v=juZqGU9iuq0
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Dec 1, 2015 10:19
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No. 9 posted:Reminds me of this Surely it would be cheaper to install a permanent pillar containing a compressor and air drier? (assuming that they're using purge nitrogen continuously)
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Dec 1, 2015 11:51
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chitoryu12 posted:I was on vacation in NYC this past week and I was walking back to the hotel after lunch on Thanksgiving, when a ton of sections of streets and avenues are closed to traffic for construction of poo poo like holiday markets. One of the traffic signals was opened up at the ground, and the wiring they had pulled out of the post caught my eye. I'm not an electrician, so how does this look? On a related note, is it bad for the cover to open like that? Occasionally I see someone has taken the cover off one of the light poles around town. Nobody around, no work being done, likely the work of a hooligan. The first time I noticed one I called city hall so the maintenance guys could fix it since it might not be noticed by city workers for days or weeks, and it seemed bad for rain and rats to be able to get into the hole. I've seen it a couple times since then and just frowned at it as civic duty wrestles with social anxiety. Is this something I ought to call in, or it is fine for the access hole to be open for a few weeks?
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Dec 1, 2015 12:15
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Not your problem, don't worry about it.
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Dec 1, 2015 14:37
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Angela Christine posted:On a related note, is it bad for the cover to open like that? Occasionally I see someone has taken the cover off one of the light poles around town. Nobody around, no work being done, likely the work of a hooligan. The first time I noticed one I called city hall so the maintenance guys could fix it since it might not be noticed by city workers for days or weeks, and it seemed bad for rain and rats to be able to get into the hole. I've seen it a couple times since then and just frowned at it as civic duty wrestles with social anxiety. Is this something I ought to call in, or it is fine for the access hole to be open for a few weeks? Some people (meth-addicts mostly) like to steal the covers off light poles to sell as scrap. Unfortunately for the city, the covers are kind of expensive and that's assuming they're even still available so they usually just stay open until someone electrocutes themselves and then they have to go weld blank plates over the holes that will have to be cut off for maintenance. ...or so I've been told. I don't have any firsthand knowledge.
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Dec 1, 2015 15:41
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Stolen from the GBS thread about Jewish women: Yeah,. sandals at a military base, REAL good idea. Also, does SA not care about image leeching anymore? I originally copy and pasted the link from the original thread, and it was straight from some Israeli blog, not Imgur or some other image host.
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Dec 1, 2015 16:25
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DrBouvenstein posted:Also, does SA not care about image leeching anymore? I originally copy and pasted the link from the original thread, and it was straight from some Israeli blog, not Imgur or some other image host. E: My memory isn't as good as I thought it was, image leeching rules are still enforced in some cases, so err on the side of caution. Alereon fucked around with this message at 01:30 on Dec 2, 2015 |
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Dec 1, 2015 18:17
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DrBouvenstein posted:Yeah,. sandals at a military base, REAL good idea. lmao
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Dec 1, 2015 18:22
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Alereon posted:it's been a long time since someone was probated for leeching I got quite the probation for it recently. 
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Dec 1, 2015 18:24
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No. 9 posted:Reminds me of this Yeah, I passed those last week as well. Nice to know they actually have a purpose and weren't just accidentally left there!
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Dec 1, 2015 18:56
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