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Johnny Aztec posted:As a dumbass kid.... My "the hard way" lesson was cutting out a resistance heating element in an induction hvac unit. I turned off the power at the unit but didn't test it properly. Turns out it was back-fed and when my pliers cut the lines it shorted 277v to the neutral. There was an ear-ringing bang and I was fortunate that the unit contained the chunks of the cutter that exploded. Tenants in the suite thought it was gunfire, but no, just an idiot tripping an 80ish amp breaker with a direct short. Oh, and it was Federal Pacific gear too, so I was really lucky it wasn't worse.
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Jan 29, 2018 17:47
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I'm just lucky I only ever get bit by 120V in one hand. Just a little tickle to wake you up. Anyways, reading through the last couple of pages, were there people thinking we (USA) use 120V three phase? Because that's not quite right. You typically see 208V, 230V, or 460V on our three phase systems (line to line voltages). On occasion, you'll see a 575/600V site like our Canadian friends like to use. What's really fun is when a motor is built for 230 or 460 operation, but it's labeled as being "able to work" on 208. The trick to that is that it really needs to be 208 or higher. Even a slight variance down to 206V can be enough that motor overloads start tripping and poor techs out in the field are pulling their hair out over it.
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Jan 29, 2018 18:55
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Johnny Aztec posted:As a dumbass kid.... 
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Jan 29, 2018 19:38
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Memento posted:A friend of mine is a property manager. He has a block of 8 apartments in a nice neighbourhood where the roof partially lifted off in the big storms we had here in late 2016. It lifted up in a big gust of wind, then slammed back down, causing structural damage to the building as well as messing up a lot of the plaster and paint inside. They got an engineer to get into the roof from the inside and check out the roof ties, which were obviously hosed in one way or another. That seems completely normal... for a traditional hut in the Alps...
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Jan 29, 2018 19:42
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Johnny Aztec posted:As a dumbass kid.... I lost my electrocution virginity at about 10 years old to a 15,000 volt (30ma) neon sign transformer what could easily pull 3 inch arcs. I got a little too close one day while screwing around, and it bit me, and lit me up. It's still sitting on the shelf in my garage.
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Jan 29, 2018 19:57
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Explosionface posted:I'm just lucky I only ever get bit by 120V in one hand. Just a little tickle to wake you up. Yeah, but 208V line-to-line is 120V line-to-neutral, which is why you see 208Y/120 or something like that.
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Jan 29, 2018 20:00
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Phanatic posted:Yeah, but 208V line-to-line is 120V line-to-neutral, which is why you see 208Y/120 or something like that. Right, which is why it tends to be popular (in more office type settings). 208 for bigger stuff, and three legs of 120 for anything else.
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Jan 29, 2018 20:13
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glynnenstein posted:My "the hard way" lesson was cutting out a resistance heating element in an induction hvac unit. I turned off the power at the unit but didn't test it properly. Turns out it was back-fed and when my pliers cut the lines it shorted 277v to the neutral. There was an ear-ringing bang and I was fortunate that the unit contained the chunks of the cutter that exploded. Tenants in the suite thought it was gunfire, but no, just an idiot tripping an 80ish amp breaker with a direct short. Oh, and it was Federal Pacific gear too, so I was really lucky it wasn't worse. I was 4 or 5 years old when I got my taste of electricity. I was walking barefoot on the backyard, right after my grandma cleaned it up. Pools of water everywhere. I look down, and there's an extension cord that's half plugged in to another extension cord. I grab it. I remember falling down, completely rigid and paralyzed and bashing my head against a nearby plant pot. Next thing I know, I'm on my father's lap, 1/3rd of my index finger covered in a 3rd degree burn, and another smaller 3rd degree burn on my middle finger. First and only really dangerous accident I've ever been in
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Jan 29, 2018 20:21
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I'm confused about what sort of mess in a yard requires water at all to clean, let alone enough to make pools, and why there'd be a live extension cord in one of those said pools.
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Jan 29, 2018 20:23
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Baronjutter posted:I'm confused about what sort of mess in a yard requires water at all to clean, let alone enough to make pools, and why there'd be a live extension cord in one of those said pools. Electric power washer on a deck or patio comes to mind.
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Jan 29, 2018 20:27
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Baronjutter posted:I'm confused about what sort of mess in a yard requires water at all to clean, let alone enough to make pools, and why there'd be a live extension cord in one of those said pools. gently caress if I know, I was just a young capacitor
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Jan 29, 2018 21:11
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Collateral Damage posted:When I was a kid I learned that if you have a helium balloon that's partly deflated it will stick to the front of your crt TV. I also learned the hard way that said balloon turns into a big capacitor and will shock the poo poo out of you if you touch it after a while. My first difficult lesson about electricity was when I mistook the cooling slots on the top of the TV for a piggy bank when I was 4
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Jan 29, 2018 21:36
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Jan 29, 2018 21:40
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Look, they make the claw on the back of a hammer for a reason
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Jan 29, 2018 21:42
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Its just a fingernail
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Jan 29, 2018 21:43
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Synthbuttrange posted:Its just a fingernail boooooooooo
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Jan 29, 2018 21:44
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Dude's lack of peripheral circulation is the real danger
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Jan 29, 2018 21:57
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shame on an IGA posted:Dude's lack of peripheral circulation is the real danger his vasoconstriction couldn't possibly be related to the flood of epinephrine released from a nail driven into his finger
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Jan 29, 2018 21:59
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Car looks american, I vote diabeetus.
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Jan 29, 2018 22:01
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Synthbuttrange posted:Its just a fingernail 
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Jan 29, 2018 22:02
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Synthbuttrange posted:Its just a fingernail 
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Jan 29, 2018 22:22
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'Hurt' by Nine Inch Nails begins to play in the background.
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Jan 29, 2018 22:27
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Jesus!
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Jan 29, 2018 22:30
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Stoatbringer posted:Jesus!
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Jan 29, 2018 22:31
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Look it says sturdy what more do you want?
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Jan 29, 2018 22:59
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LifeSunDeath posted:Look, they make the claw on the back of a hammer for a reason It actually took me like 3 looks over this to realise the nail is through his finger. I thought it was something dumb like he was holding it next to an exposed 500kv wire or something.
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Jan 29, 2018 23:07
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dis astranagant posted:Nearly everyone has experienced a shock in the tens of kV from good old static electricity. I don't know what the voltage was, but my shocking moment was with a paper shredder that had jammed due to a fuckton of shredded material ending up in the inner workings about 4 years ago. I had disassembled it down to the main mechanism on top of the collection bin, and I tried lifting the circuit board out to clean under it....without unplugging the machine (I had it plugged in to test some stuff with the blades to see what was jammed). It felt like my fingers were suddenly vibrating rapidly until I dropped it.
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Jan 30, 2018 01:19
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I had an ex whos parents had a house. When the lived they they wired up some deck lights with a length of romex attached to the outside of the deck, held on with wire staples. They eventually moved out and rented the house to her aunt and family. The family hooke the dogs leash to the romex and let him use it for a run and after a while it rubbed through the wire. It was raining one day and the father came home and fount his wife and kid both dead in the yard, as near as anyone figured out the kid went out to unhook the dog and was electrocuted, the mother saw her kid and went to help and suffered the same fate. the dog was fine though.
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Jan 30, 2018 01:32
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chitoryu12 posted:I don't know what the voltage was, but my shocking moment was with a paper shredder that had jammed due to a fuckton of shredded material ending up in the inner workings about 4 years ago. I had disassembled it down to the main mechanism on top of the collection bin, and I tried lifting the circuit board out to clean under it....without unplugging the machine (I had it plugged in to test some stuff with the blades to see what was jammed). It felt like my fingers were suddenly vibrating rapidly until I dropped it. I had encounters with an improperly trimmed comb rail and a screw terminal with very liberally stripped conductors. I know that feeling.
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Jan 30, 2018 01:38
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4th of July from a show being launched off the end of a pier. I don't think the one on the bottom was supposed to detonate only 50ish feet over the technician's heads:
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Jan 30, 2018 02:05
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Fabulousity posted:4th of July from a show being launched off the end of a pier. I don't think the one on the bottom was supposed to detonate only 50ish feet over the technician's heads: Happens all the time.. shell not fully at the bottom of the mortar, or insufficient lift charge from poor manufacturing or shipping damage etc. “Low Break!!” If you have good PPE you’ll be fine 
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Jan 30, 2018 02:28
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Phanatic posted:It's not the amps *or* the volts. It's the joules! I can understand the need to kill yourself when you put in in those terms.  (USER WAS PUT ON PROBATION FOR THIS POST)
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Jan 30, 2018 02:40
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Explosionface posted:What's really fun is when a motor is built for 230 or 460 operation, but it's labeled as being "able to work" on 208. The trick to that is that it really needs to be 208 or higher. Even a slight variance down to 206V can be enough that motor overloads start tripping and poor techs out in the field are pulling their hair out over it. I think you can use a autotransformer to go up from 208V to 240V or down. Or 277 down to 240. But you cannot use an autotransformer to go from say 277V to 120V or 4160V to 480V because it provides no isolation like a regular two-winding transformer does. Also here are all the AC voltage combinations I heard of: 69/120 120/240 (Edison two pole) 120/208 240/400 277/480 347/600 580/1000 (mining equip???) 2400/4160 4160/7200 7200/12.5k 13.8kV 34.5kV 69kV 138kV 345kV 500kV 1000kV (one test transmission line in Japan)
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Jan 30, 2018 03:12
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chitoryu12 posted:I don't know what the voltage was, but my shocking moment was with a paper shredder that had jammed due to a fuckton of shredded material ending up in the inner workings about 4 years ago. I had disassembled it down to the main mechanism on top of the collection bin, and I tried lifting the circuit board out to clean under it....without unplugging the machine (I had it plugged in to test some stuff with the blades to see what was jammed). It felt like my fingers were suddenly vibrating rapidly until I dropped it. Lucky. I'm from Alabama, so of course we had a beer fridge outside under a shed, with nonexistent grounding. I go to get a soda in drizzly weather, and my bare feet complete the circuit. The muscles of my hand clench around the refrigerator handle, and I can't let go. Thankfully, dear ol' Dad put the electrical receptacle at about eye level to my 10-year-old eyes, and I was able to unplug it while screaming like a banshee. To his credit, Dad hammered down a 6-ft grounding rod later that day.
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Jan 30, 2018 05:17
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Three-Phase posted:I think you can use a autotransformer to go up from 208V to 240V or down. Or 277 down to 240. But you cannot use an autotransformer to go from say 277V to 120V or 4160V to 480V because it provides no isolation like a regular two-winding transformer does. The soviets had an 1150kV line for a while in the 80s but it's since derated to 500.
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Jan 30, 2018 05:41
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Jan 30, 2018 06:22
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Floppy disks are less floppy than I remember.
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Jan 30, 2018 07:31
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 https://i.imgur.com/fbM7DK0.jpg
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Jan 30, 2018 08:18
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Character design looking good.
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Jan 30, 2018 08:22
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Nice eye bolt.
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Jan 30, 2018 08:23
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