Could you just pop into the network room and check- hello? The Away Team. They're... gone Friday is upon us once again, and as the week disappears into the rear-view mirror we have another tale from those princes and princesses of the pager in our regular On Call column. Today's helpdesk ticket comes from "Christopher", a member of that hardy tribe that like to refer to themselves as "On-call engineers". …
Testing the PDU's in some racks to make sure none of the servers had both PSU's plugged into one side.
Dull ol' me turned off one PDU - good, nothing went down. Then for reasons I still don't understand, I reached in and turned off the second one. Which might not have been quite so dumb had I at least turned the first one back on, but no...
Back in the distant past when I used to fix hardware to component level, I've had many a PSU go bang whilst working on it - dry electolytic capacitors being the favourite, of course.
Also, years ago whilst working in a electronics depot we were killing some time by rebuilding a time code display in order to get it to count backwards (long story) and someone wired in a rather large (physically) electrolytic cap into the power supply.
Upon powering up the unit we were greeted with a increasingly loud screech immediately followed by a very loud BANG. upon opening the unit we found the entire box packed with small bits of wax and aluminum shards. every crevice and under every component.
That was the end of that project (nobody wanted to pick out all the bits).
Ah, brings to mind, a time in college. A morning after a inordinate amount of tequila, I strolled into the electronics lab. Took over from my not so compitant lab partner and immediately inserted a cap backwards...
The aged professor not amused, turned a worrisome color, the breadboard was worse for wear.... the shower of fillings was pretty though
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I lost my hearing for a couple of days when a large electrolytic capacitor decided to disassemble in close proximity to me. Even 6 months later, well after the acrid vapours had passed, we were still finding bits of paper and plastic in completely illogical places.
The other unanswered question is how exactly the cram so much stuff into such a small package as its clear after they go pop that it shouldn't have been possible to fit it all in there in the first place..
I remember an occasion in the mid 1960s when a pair of 50,000u caps committed suicide. They were fitted to a seriously meaty 48V PSU. This was also at the time some of them instead of having +/- or red/black markings, had a square and triangle (I still can't remember which was supposed to be which). It's hardly surprising that one got through to final test - fortunately to a old and grey test engineer (who'd already complained that you had to reach over the kit to turn the power on).
Well, they exploded with such force, that the cans themselves shot out of their clamps and embedded themselves in the asbestos roof. Any other guy would have been killed instantly, but this old bird apparently instantly realised something was very wrong and dived under the bench.
P.S. I was the most junior of junior trainees at the time.
1970s. The rectifier 7 on the TV chassis failed short, putting mains across the 400uF + others multisection capacitor. Valve TV (or mostly). I ducked when it warmed up and I heard a very loud hum. Then the capacitor exploded putting bits of aluminium in the concrete block wall. Amazingly the TV did work just with putting a BY127 and a replacement multisection cap from a scrap TV.
Fast Forward to 2005
Fitted a PCB to an old Racal designed Transmitter/Receiver, NOS that had never been fully assembled. About 1/2 the tantalum caps ejected glowing orange beads of doom with a massive bang. As far as we could tell there was a batch of the blue bead caps that had been printed on the wrong side. The board worked fine with replacement caps from Farnell.
Solid (MnO2) tantalum capacitors in a large enough case (size D or larger) are damaged simply by the manufacturing process (reflow) and if they are decoupling a low impedance source (such as the output of a power supply) they can become quite spectacularly pyrotechnic and produce enough magic smoke to take out the entire box.
On another occasion, the regulator for an FPGA which should have provided 3.3V had the input and output pins shorted (solder blob) so the FPGA was being driven by 5V. By the time I figured out something was wrong, the shape of the silicon die had actually been imprinted on the plastic case.
Fun times indeed.
Many years ago - had a phone call from a user asking if it was normal that her CRT monitor was leaking smoke out of the top and that there was a funny smell..
Before I could say the immortal words "turn it off!" I heard a large bang and a very loud squeak from the user. Her CRT had just imploded..
Luckily, her phone was off to one side so she hadn't been caught by any of the bits of coil that were ejected post-implosion. We did have to replace her PC though - the (onboard) video card was utterly fried. She also got a shiny nice new CRT as well - and a very, vey clean desk as we thought it was a wise idea to clean up all the brown-grey residue..
Many years ago, while working in a PSU factory, we suddenly had a spate of units going up in flames in final test. It was spectacular, but annoying. The problem was traced to the brand-spanking-new new, and amusingly named, ATE system I was working on. I'd just finished the test programme and was trying it for the first time on a batch of high voltage PSU PCBs. The ATE results were printed on till-roll sized bits of paper. We needed to compare the ATE results with final test so I just folded these up and stuffed them into any convenient nook/cranny on the PCB where they wouldn't just fall out during the final assembly. The bit that I didn't give too much thought to was that the paper was that silvery thermal stuff that's also conductive........
That wasn't the Marconi System 80\ATE was it? - That's a nasty flashback to my Racal days.
Icon exploding electrolytic (Had 4 fairly beefy ones in a Racal manufacured 24V military vehicle power supply - That erupted spectacularly if wired up incorrectly).
The other thing that I recall about these power supply's is that they were mounted on two strip's of wood (painted metallic blue) during testing & one of them was fitted with roller balls to move them around on the test bench, the other acting as a brake.
There had been a time when they were mounted on two bits of wood, both with roller balls, but one had rolled off the work bench, on to the testers foot, flattening it in the process & the top of the steel capped shoes he was wearing was pushed back into his toes effectively amputating them either as the direct result or after they cut away enough of his shoes to extract the metal from flesh.
At college learning about electronics many years ago....
The first exploding capacitor was accidental - the rest were not.....
Dealing with 19" CRT monitors as a trainee in the last centry, the caps were the size of a small drinks can, and were not soldered on, but screwed on. I had to change one for some reason, some one had scratched a "+" on the PCB. I'm not going to follow that, I'm going to put the cap in according to the proper manufacturer's markings printed on the board.
Once the smoke cleared, I was informed that particular model of board had an error with the markings on the board.
"The first exploding capacitor was accidental - the rest were not....."
At one training centre I attended, I was informed that anyone attaching 1000uF caps backwards to the 48V supplies and hanging them out the 2nd floor windows would be subject to disciplinary action.
Apparently there had been a lot of complaints.
Back in high school, a friend of mine and I built a railgun for a physics class. (I suspect that teacher doesn't work there anymore...) Being on a near-zero budget, we went by quick film developing places to get used disposable cameras (minus film) to scavenge the capacitors from them. We soldered 150 capacitors, of about 150 uF each, to a couple of metal rails.
I was, regrettably, not there when he hooked it up to a bridge rectifier and 120V to test it out. Apparently one capacitor was connected backwards, and it did not disappoint - a bang and a 3-foot jet of flame!
First year Electrical Engineering lab class. Somebody (not me) discovered that charging a Sprague Orangedrop 0.01 µF capacitor to 200-300v and tossing it to a classmate would elicit a satisfying howl.
Forty years later, and I still avoid catching stuff tossed to me by surprise.
A similar thing here. Back many years ago in college I had an electronics class. There were two levels, an into class and an advanced class. We shared the lab and lecture hall (there were large windows between the lab and lecture hall). They had it scheduled to where the intro class would have lab first, then lecture, and for us in the advanced class it was the opposite.
We had a couple of variable DC power supplies that would go up to 400V. The favorite thing was to take a few mid sized electrolytic caps, charge them to 400V and leave them laying around on the benches for the next class to discover. Have the big windows between rooms made for great entertainment!! Al least it tough the into students to respect capacitors and to discharge them before working with them!
"The favorite thing was to take a few mid sized electrolytic caps, charge them to 400V and leave them laying around on the benches "
Not so funny to me.
In my high school second year electronics, another guy was trying to save the stereo part of a tube console TV stereo. Of course the power supply was in the TV chassis. Wanting to modernize it a bit, He rewired the power supply to use silicon diodes. When he first tested it on the bench he was mystified it didn't work. The stereo tubes all lit up and the voltage on the filter cap was good. I happened by and took a quick look.
And put one hand on the bench.
One howl later (ok maybe more than one) and I had a suggestion as to where to look for the problem. My guess was the ground wire was missing between the two chassis. The chassis happened to be one hands width apart. My hand had completed the circuit.
Later I saw that I had a small white spot of burned skin on my knuckle.
They used to do that to apprentices in the repair center I worked at to teach them not to try & catch things. They also had this nice conductive paint. It was only conductive once it was dry, though...
Cue someone* painting the prongs of a 240VAC plug, replacing it in the GPO & wandering off... Nothing happens at first, but then as it dries, it starts conducting a little via high resistance. I^2*R=>heat. Paint starts drying faster. The faster it dries, the more heat...
I'm told it was about 20 minutes later that the power point exploded.
*I was told about it. It occurred before I started there.
They also had this nice conductive paint
My dad used to regale us with tales of what he got up to at Uni - one of which was to make nitrogen tri-iodide[1] and then, while still wet, paint it in thin strips across the cycle-path.
It would then dry[2] and, once dry, make a nice bang[3[ as someone rode over it. He was politely[4] asked to desist by his course tutor.
Pharmacy students eh?
[1] Don't try this at home people. It''s incredibly unstable and, in sufficient quantities, can do serious damage.
[2] Sometimes. Other times the rain would wash it away. He went to Uni in Birmingham.
[3] In small quantites it's pretty benign. In larger quantites, not so much. Please don't try this at home, no matter how much you dislike cyclists..
[4] The first time. The second time, not so polietly with a distinct overtone of "do this again and you are out". He didn't do it again.
capacitor to 200-300v and tossing it to a classmate would elicit a satisfying howl
As does wiring up a Van der Graff generator to the classroom inside brass door handle and then turning it on. Which only works if it's connected to the outside door handle by a nice metal bar of course.
Err.. allegedly.
I will admit to trying to impress girls by using a VDDG to light Bunsen Burners by standing on a milk-crate, putting one hand on a running VDDG and then pointing a finger at a turned-on bunsen at close range. It lit the bunsen but that's about all it did..
I'm amazed that I survived childhood.
FYI...
Defibrillator Capacitor
Capacitance range: 32 to 200 uF.
Rated Energy:150 to 500 Joules.
Dissipation factor 120 Hz: 2.5X10-3.
Rated voltage: 1800 to 6000 VDC.
Test Voltage : Between terminals: 110% rated DC voltage for 10 seconds. Terminal to case: Up to 10 KVDC.
Typical operating life: 2000 to 10,000 Cycles.
Temperature range: -40°C to 65°C.
I've worked with these for 20 years and never seen or heard of one exploding. Suddenly I feel very glad of that. I suppose to overload one of those to the point of detonation takes more than one wall socket.
The first exploding capacitor was accidental - the rest were not....
Ditto for 12v transistors. The first time we accidentally put 415v through one was an accident, the following times not so much.
They can glow like an LED for a short while - before the top departs upward at high speed. We were made to replace the suspended-ceiling tile above our bench as the sight of several transistor tops embedded in it wasn't thought to be good as it might encourage others..
. . . .the time: 1998
The place: Capitol College, Lanham, MD (just north of DC)
I was teaching a course to develop the first set of Windows Admins/Engineers for a large, unspecified Federal Agency in the Fort Meade, Maryland, vicinity.
Part of this was A+, part was Windows NT4 MCSE, and part was Linux and Cisco.
I jokingly referred to "magic smoke" being the key to computing. One of the students demanded I show them some "magic smoke".
Luckily, we were in the lab, I had a whole stack of discarded AMD K2 motherboards, and a number of variable power supplies.
Wired it up. set the 5 volt feed to 30 volts, and the 12 volt feed to 75 volts. Inside of 5 seconds, hilarity ensued. Capacitors were popping with little bursts of flame and large bursts of. . . "magic smoke".
But as I was pointing out the "magic smoke" to the class, I had neglected to power down the supplies.
And someone asks, "Is the CPU supposed to do that ?".
I take a look back at the mobo, and the CPU has deformed about half an inch. . . and suddenly BANG, burst of flame. . . and no CPU. Well, at least on the mobo: it had embedded its' remains in the ceiling, 10 feet above.
Now, **THAT'S** entertainment. . .
Just recently walked into a small comms room on one floor of a very large building. The temperature was toasty because the aircon had failed. There was a non IT manager working in there on the single PC in there who commented how nice and warm it was for once. I immediately said it shouldn't be anything like this temperature and that I needed to use the phone. Whilst dialing building services to get this fixed the manager points out that on the wall box behind her there are only three lights on. She then confessed that had made her nervous and had considered flicking the switch on it. I said that there are only supposed to be three out of the four lights on. "That's the IT power supply switch for the room and the left two indicate that we are using supply 1 and it is healthy. On the other side are identical lights but only one is on indicates we're not using that power supply but it's there if we need too. Don't touch that box or indeed anything else in this room except that PC."
Arrived in Lagos in August 1993 to carry out network support, 2 hours before there was the coup that put Abacha into power. Not any explosions as I recall but I did see someone being executed by firing squad.
Arrived in Bangkok morning of 19th September 2006 to solve router problems, just as there was a coup. Had the new router smashed by a Thai squaddie, but not many explosions on that trip.
Had to fix a domain server in Washington DC on 4th July once - plenty of explosions.
Obviously, you were the one organizing the various coup. Are you sure you don't want to post under anonymous identity?
2006 coup was very uneventful if you were just outside of Bangkok: a couple of armed trucks parked along the road, but else, it was business as usual.
Can you please keep me advised of your itinerary, so that I know what places to avoid!
Many thanks.
Back in the early 90s, I was working for a company that ran elections for countries. We had one project in Angola. I was asked if I wanted to provide local support... But I had "misplaced" my passport.
The people on site were staying in a villa with large grounds, the guards showed them a point 50 feet from the house and said, if they went beyond that point, they were on their own! If they left the compound, they had to radio in every 5 minutes during their journey.
The day of the election came and the incumbent won, which the rebels saw as collusion and the election team had a running gun battle back to the airport!
I was so glad, that I had "misplaced" my passport.
At FCO there was one chap who was a very senior member of the Queen's Messengers (diplomatic couriers, of which there are only around 25 or so). He had travelled to just about every war zone on the planet, including delivering to the UK mission in Saigon during the evacuation, helping to evacuate our embassy in Tehran upon Khomeini's return, being held in Kuwait upon Iraq's invasion and countless other conflicts. We always used to consult with him before travelling to any suspect countries as he always seemed to know which ones to avoid .. even several weeks in advance of a coup.
The closest I got to something remotely similar was while doing a software training of a new customer in Kuwait. About a month or so before the second Iraq war. Air raid sirens went off. Attendees all laughed, saying 'yeah, normal, just exercises or prep for when it really happens. it would have been announced in the local newspapers.'
That was my code brown moment :-)
Years ago, in a different life of wearing uniforms...
We had been operating a comms relay station in a remote and presumably rather safe location. One lazy afternoon, one of our microwave links went down. That wasn't so unusual and I sent a team to check antenna and amplifier which were a few hundred metres away. As I talked to them on the phone, trying to isolate the problem, he suddenly said: "WE'RE UNDER ATTACK" And the line went down.
In the end all of us were fine. But somehow I'm still amazed how quickly a whole, snoozing squad can reply.
I once had to call out an "away team" to fix a microwave link in rural mid-Wales.
Contractor reports back "WORK ABANDONED DUE TO UNDESIRABLES AT BASE OF TOWER".
I wasn't having any of it... "It's in the middle of nowhere, and it's on the top of a hill. If I find out those 'undesirables' turned out to be nothing more than a flock of sheep, I WILL be escalating this call !"
"It's in the middle of nowhere, and it's on the top of a hill. If I find out those 'undesirables' turned out to be nothing more than a flock of sheep, I WILL be escalating this call !"
Personally I've always found sheep to be undesirable - except, perhaps, when roasted and accompanied by mint sauce.
Meanwhile, in Australia .......................
I once designed a rack of TTL and CCD shift registers. I had a habit of swapping cards without powering down the rack. Once, when I did this, there was a large POP and a tinkling sound as parts of a chip cascaded down the rack. Inspection showed that the ceramic casing of one of the CCD shift register chips had blown off and all that was left were the pins and some of the silicon chip. I never did figure what happened (perhaps the chip was plugged in backwards). It did make me jump though.
Yes, I did continue to swap cards with the power on.
floor tiles in a comms room to pull a cable and your hand comes out wet
It's even worse if your hand comes out wet and then you notice copious rat droppings are now stuck to your wet hand..
I know of one datacentre where they (very, very unofficially) have a pair on on-site cats since their rat problem couldn't be solved by the usual exterminators (fumigation would have done it but that would involve shutting down the whole DC).
Took the cats 3 months to clear the rats - the problem was that cats (generally) won't eat rats unless they are very, very hungry. So there was an amount of checking under the raised floors to clear up corpses until the place was clear.
(Turns out that there was an old drain in one corner of the site that had crumbled where one of the new walls rested on it, leaving just enough space for the rats to get in. And rats seem to like the taste of cat-5 insulation..)
A little different, our desks were moved (I was working on the Helldesk at the time) and BOFH sent the PFY down to move the power and networking tank in the floor.
I don't know what I had done on that day to annoy the BOFH and the PFY, but the PFY rotated the tank 90° before plugging it back in (which should have been impossible, but you know the PFY and prodding things in holes where they don't belong)...
Anyway, long story short, I plugged in my PC and BANG! A 2 foot spark shot out the back of the PC's power supply, accompanied by an ear splitting bang and lots of smoke. I regretted that I had started with the PC, the monitor was on its last legs, but management wouldn't replace it.
Now, I am the local BOFH.
In another office, in Germany, the wall sockets have the earth exposed, so that it is the first thing that gets contact when plugging in equipment - it is also jolly useful when using anti-static equipment, you just clip it onto a spare earth prong... Only the electrician must have been half asleep as he wired up the socket in my office. I was standing against the window, concentrating on my whiteboard, when I lost my balance and reached out for the windows ledge behind me. I missed and stuck my hand in the socket. Not a problem, the earth gives a little jolt if you have a lot of static build-up on your body (nylon clothing, for example), but otherwise totally harmless.
Only, ZAP! I was flung away from the wall and my shoulder hurt badly and my whole arm, come to think of it! I reported it to the technicians, they didn't believe me, until they stuck a tester on the earth prong... The electrician had crossed the earth and phase, so the full 230v were flowing through the earth prong! I had a lucky escape, all things considered.
It's not stupid to make a mistake - happens to all of us sometime.
Where the failing was (imho) is in not testing the socket afterwards. I have a little tester (cost a tenner on Amazon) which plugs into a socket and uses a set of LEDs to show whether the connections are correct or not. I would expect any electrician to use something similar after installing/replacing any socket, especially one with exposed metalwork...
In Germany electricians have to do an apprenticeship and the head an electrical firm has to have his Meister Certificate (Master Craftsman).
The guy who did the wiring was a Meister, but accidents happen... Unfortunately, the company had been out of business for over a decade when I "discovered" the problem - in all that time, nobody had (luckily) ever plugged anything into that socket!
Hm. Smug English Person talking trash about the electricity supply. Time for a tale:
I got home from school and turned on the lights. They seemed very bright. Turned on the TV. That seemed very bright. Powered everything off and waited for Dad to arrive in theatre from his Technical College Teacher job.
Told Dad, who dug out his Avo and did some poking around in a socket, then at the fusebox. Then got on the 'phone to the Electricity Board to complain about there being a 44ov supply Chez Us. Was ridiculed by EB phone guy, but they dispatched a technician when Dad trotted out his Chartered EE status in stern tones.
Technician arrives in full "pooh-pooh" mode, pokes a tester into the nearest socket, squeaks loudly and grabs the phone to yell that there is indeed a 440v supply at Chez Stevie and probably for the whole street and the next one too.
A quick trip to the little substation in the next street proves what Dad already knew: some "properly qualified" electrician had connected our street supply across two phases instead of the phase and CT.
All this went down in in the Early to late summer evening, Merrie England. Whitmore Park, Coventry to be exact. The little substation was on Harborough Road, top of the hill, next to Rotherham Road. It's the shed with a green gate these days, according to Google.
Ah, the days when technical teachers were tradesmen who could actually do the stuff they were teaching.
My physics teacher: former British Steel metalagist.
My chemistry teacher: former ICI industrical chemist.
My electronics teacher: former electronics engineer
My geography teacher: former olympic javelinist (ok, analogy falls down a bit there)
My electronics teacher: former electronics engineer
At polytechnic we had one lecturer that *everyone* respected - he'd spent 30+ years as a GPO engineer and was also a major in the Territorial Army (as it was then).
He knew his stuff and was also a very, very good lecturer - he made the digital electonics and signalling courses enjoyable and we actually learnt stuff.
His colleages however - one had all them empathy and teaching ability of a lump of granite and the other one was doing his masters and seemed more focussed on chasing the female students than actually bothering to teach.
Which is (one reason) that I failed the analogue electronics part of the course and ended up dropping out. Which was a shame because the computer modules I was averaging 90% and about 70% in the signalling modules.
The engineer installing one of our machines was told that he had to let the customer's electrician wire it in - because he was the shop steward.
Said electrician wired up a bog-standard MK Electric switch box without connecting the neutral lead.
The electronics in the machine thus found itself connected across two phases (the machine included a bloody big squirrel cage motor using three-phase) and let the smoke out.
I've run across "we're union and we're in charge so everything stops because we say so" nonsense occasionally. My standard answer is to ask "Is your union fully certified in the installation of equipment that uses dynamic bandwidth allocation over adaptive differential pulse code modulation?" ... usually shuts the idiots up, sends 'em off with their tail between their legs and allows me to get on with the job.
Tee hee. My first job was in the late 70s and in a closed shop running under the iron screwdriver of the ASTMS (at least, the IT bit; there were several other unions in the mix as this was a manufacturing plant).
I come in one morning and our chief programmer is whining because the heat is off and her little one-bar electric heater has a blown fuse. She is moaning because this has happened before, and it took hours for the Electricians to dispatch someone to fix it. No problem I say, do some quick arithmetic (1000w/240=4 anna bit amps) and I fit a 5 amp fuse I just happened to have in my pocket no I don't remember why.
I go out of the office to do some stuff in spares and come back to chaos. I am called into Mr Rumbold's office (in fact this is the guy who was in every way the model for Dilbert's boss, down to the hairstyle and dimwit observations) where the head electrician is sitting. I get a lecture about how I am not a member of the electrician's union, how my doing electrical work results in an unsafe installation that could "kill someone".
When Mr Sparky has wound down and Mr Rumbold has finished mournfully shaking his head I ask if I can speak.
I point out that the electric fire had been repaired by a union electrician the year before. Mr Sparky agrees. I then pull out the blown fuse I took out of the plug and drop it on the desk in front of him.
"In that case I don't understand the fuss. The qualified electrician fitted this 13 amp fuse that is about three times more tolerant of a problem than the five amp job I put in after working out the proper expected current load. Clearly I am making a better job of staff safety than the electricians are in this case."
Mr Sparky's eyes do the AWOOGA thing and Mr Rumbold hastily says "Well I think you've learned your lesson and we can agree this won't happen again", and waves to show I should leave now before I "accidentally" trigger a factory walk-out.
Another time we moved offices and had to call union desk movers. It was agreed in a lengthy meeting that Carpenters would move the wooden desks, managers for the use of, and Tinsmiths would move the steel desks, programming staff for the use of. All went well until they came across a wooden desk with steel drawers fitted. Chaos ensued. After another lengthy inter-union negotiation it was agreed that one Carpenter and one Tinsmith would move that desk. I don't know what process was used, nor how long it took, for them to decide who got which end.
I remember back in the early days of my career, I worked for a small (now defuct) fledgling ISP. Being small, money was tight and everything was done by the seat of the pants but there was demand for our hosting service - more than we could have predicted. I remember my boss buying a "new" UPS to power our rapidly filling server racks. The boss decided to get the father of our of our engineers, who was a qualified commerical electrician, to fit it.
A few weeks later, one of the junior engineers was in the server room and came back to the main office complaining the room smelled of fish. A few moments later, the building went dark. We went over to the server room to investigate and were greeted with clouds of smoke.
When everything calmed down, one of the battery packs attached to the UPS was heavily blistered and it looked like that was the root cause. Being child like of course, we never let the unfortunate engineer who's father had connected the UPS for us at mates rates, live it down!
A friend of mine reached behind a large bank of relay racks and managed to get his Rolex watchband across the 48V supply ... The resulting loud "CRACK!" and fans spinning down, coupled with the smell of roasting/burning pork, were rather disturbing. To say nothing of the screaming. I managed to calm him down & get him to the ER ... X-rays showed little balls of gold melted into his wrist behind the 3rd degree charring. The surgeons later told him he was lucky to still have full use of his hand. Today, 35ish years later, the scarring is still impressive despite skin grafts. He got a new band for the watch, and now wears it on his other wrist. It still works.
And people wonder why I always take off my wedding ring when working on electrical stuff. Yes, that includes the cars, trucks, boats etc.
That's why my work (industrial maintenance these days) watch is always a Wal-Mart special with a rubber watchband. Minimizes both electrical and mechanical hazards.
My wedding ring either stays in the truck or goes into my pocket when I'm working. Although several of my co-workers wear those silicone rubber rings in place of their wedding band while working.
==> Icon: I still have all my digits.
De-gloving & metal watchstraps.....
Having only suffered a light buzz from a metal watchstrap being in proximity to a 250W RF amp combiner (Racal again) I present the following short stories of horror.......
Mr "K"Nornan (The Knorr soup adverts where prevalent at the time) our history teacher told a tale of one his fellow teaching students working on the railways during the holidays, open goods carriage door, moving train & a ringed finger in wrong place then very suddenly a distinct lack of either.
HNC student & former TV Tech (Tossing the charged cap) while working on a old ladies TV, had to drop his arm between vertically mounted boards to make an adjustment, his metal watchband hit the HT, screams & a rapidly pulling of his arm away resulted in lots more shocks & deep scratches from the solder joints as he did so, until standing there shaking & bleeding over the old dears carpet.
IT stores guy had a incident with a exploding coffee pot that sheared off his thumb, reattached & post surgery visit to the doctor who examined it & calmly pronounced.
"I'm afraid to say your thumb is dead, the surgery was unsuccessful!"
"Will I need to go back to hospital to have it removed?" Resigned but otherwise relaxed having just been told the bad news.
"Ohhh no I don't think so!"
A scream and stream of expletives issued forth that a Born Again Christian* shouldn't really utter, as the doctor swiftly & suddenly pulls off the now dead digit away from his hand without any further warning.
*Tommy was rarely taken as being a BAC, due to the fact he didn't let his faith interfere with his swearing.
When I was on a camping holiday in Italy with my parents, my father had trouble with his old 56 Chevrolet, one of the hydraulic lifters had collapsed and the engine was making an irritating clicking noise every time that valve opened. We stopped by the side of the road, and took off the rocker cover so Dad could screw the lash adjuster down to make the hydraulic lifter become effectively a solid lifter. Unfortunately, he accidentally shorted the live battery post to the earthed battery clamp with the metal strap of his watch, and the resultant current heated the strap and burnt his left wrist. He pulled the strap away from his wrist, thereby burning the tips of two of the fingers of his other hand, causing him to let go, and the spring loaded strap sprang back and burnt his wrist again, about an inch further up his arm, and he then repeated this action again, resulting in further burning of more of his fingers and a third burn on his forearm. He was in a lot of pain, and spent the rest of the holiday taking pain killers and liberally massaging Nivea cream into the burns. I had to do most of the driving for the rest of the holiday as Dad was feeling groggy and couldn't operate the turn signals with his burnt right hand fingers.
Worked at British Telecom back in '87, doing exchange maintenance. The exchanges had massive interleaved busbars for the 50V DC supply running above the racks, + were copper with insulation, - were aluminium uninsulated (IIRC).
Smaller strips down the height of the rack, with threaded holes every inch or so. To hook up a new unit to supply, poke a hole through the insulation on the +ive, then just screw on terminals. One day my mate Ron was doing just that, using a cable lacing tool that looked like the eye of a really big darning needle mounted on a wooden handle. I saw a bright flash and heard a 'crack!', looked over to see Ron, hand shaking, holding a truncated cable lacer... he'd pushed through a bit too hard, chipped some metal from the rack frame and shorted it. Neat puddle of metal on the floor.
My line manager also had a neat circular scar around his ring finger where his wedding ring used to be...
My uncle, a talented car-tinkerer (although maybe not as talented as he thought), was working on his old Subaru here in Oz when he managed to short his watch strap across some HV line under the bonnet.
Still has the banded scarring and inability to fully use his left hand.
Nasty stuff, that electrikity.
I always take off my wedding ring when working on electrical stuff
OldestBrother (tree surgeon) has two wedding rings - the normal one for when not swinging from branch to branch and a very thin fragile one for when working up trees - one that will snap easily if he gets his fingers caught.
One of his previous colleages no longer has a ring finger on his right hand because it got too badly broken after being trapped and crushed and his wedding ring was what trapped the finger.
I remember a visit to Apricot during the 1990's, where they were demoing their new Shogun server (levely machine back in the day...). It had a built-in UPS, and the particular machine in question had a wedding ring welded to the (permanently live when not isolated) bus bar.... it seems that an engineer had found out the hard way not to forget to flick the isolation switch before messing about inside the machine.
It was the depths of winter. I had left my last regular slave-job and registered my own company.
Splashed out a lot of money on a shiny (OK, beige) new state-of-the-art Pentium Pro mid-tower, to be my main workhorse. Acquired a Slackware CDROM and bootstrapped the system. Was working at this machine when ... bangBANG! Puff of smoke, machine went off. Dead.
The big BANG was the thunder outside. It might be an oversimplification to say so, but basically my shiny new 'puter had been struck by lightning. Cue an anxious few days (it being New Year) before I could take it in to the shop to know the worst. Happily the power supply had taken the hit, and once replaced the machine was fine, though the motherboard was ever after blackened and blistered in places.
US POTS lines had gas tube and/or carbon surge protectors where they entered the building. Back when things were done right.
Of course, fiber doesn't need that, and the data rate is much higher!
But watch out for any in-house wiring -- it acts like an antenna and even a near miss lightning strike generates enough of an EM field to induce equipment-damaging surges.
I have had a VOIP box and multiple consumer-grade Ethernet switches/routers damaged by induced EMP from near miss lightning. Garage door openers also (the light-beam safety wiring is the usual culprit -- $100 for a new control PCB). The consumer stuff has basically no protection at all on the ports. Luckily, my friends in IT keep me supplied with excess previous generation commercial gear, which does much better!
A relative needed to hook up his fax machine and phone. He only had 2 phone cables - a 6-foot one and a 100-foot one. So, the 100-foot cable ended up between the fax machine and phone, 3 feet apart, with the remainder of the cable neatly coiled under the desk.
Lightning struck a block or two away. The induced current was multiplied by the nice, hefty coil of phone wire, to the point that it blew out the fax machine and melted the insulation off of the coiled cord. Surprisingly, the phone was fine.
Moral of the story: do **NOT** use overly-long cables and simply coil the excess!
"Back in the days of dial-up, I twice had a PCI modem die after the telephone line was struck by lightning. Both times the PC was fine, and all that was needed was a new modem."
On one occasion I was woken by a flash of lightning and the sound of plastic blown off the top of one of the modem chips flying around the inside of the PC.
I was talking to a friend somewhere in small town USA. He was just recovering from a lightning strike at home. And what particularly annoyed him was that he'd recently spent $50 on a surge protector for his PC and all its gubbins.
Lighting had killed both PC (not just the PSU) and monitor, as well as TV and a few other things. When testing his surviving gear after the strike - one of the few things still working was this surge protector.
Well working in the sense of passing through power. Presumably surge protection was more of a hobby?
That won't save you. You don't need to have a direct hit for damage to occur.
I have a 65m high cellular tower with a brand new copper grounding system (to replace the one stolen by copper thieves a few years back -- never heard a thing), 300m from my house. I regularly (every year or two) have EMP induced damage.
It's the current surge what does it. Once the lightning opens an ionized channel between the cloud and earth, some very high currents begin to flow down that channel until it dissipates. That current pulse (insert right-hand-rule figure here) generates a transient magnetic field, which induces current flow in nearby conductors as it grows and diminishes. Said induced current flow can roast your electronics if they are connected to wires of any significant length (tens of meters) without appropriate surge protectors.
"It's not nice to fool with Mother Nature"
Beg to differ - the phone & cellular companies have to deal with direct hits regularly.
It's a multi level protection.
1. The tower is grounded to a buried array of radials (watching them put this in is very interesting)
2. The antennas are designed to have their tips well connected to the tower through the mounting bracket. If possible, they're designed to have their exposed metal at ground potential. All exposed metal is galvanised, and dissimilar metals protected from moisture where they can't be avoided entirely
3. The outer conductor of the coaxial cable is bonded with a heavy wire to a ground terminal where it enters the equipment shelter
4. The above ground terminal is well connected to the buried grounding radial system
5. There is a (grounded, of course) metal plate, containing gas tube surge suppressors through which the coax passes as it enters the equipment shelter. The tubes serve to remove surge energy from the center conductor and pass it to ground
6. More suppression inside, but the energy doesn't get there if the outside stuff works as designed.
It's actually quite interesting to do a Google for antenna lightning protection and see the guides these companies put out, of which this is an example.
If you ever get a chance to get a tour of a cell site, it's definitely worth it. Ask a tower maintenance tech, if you ever spot one, they're usually glad to talk about what they do.
I've been hit directly once: I was walking out of a cave when the lightning hit the rolled up metal ladder clipped to my belt and then travelled down the sodden fabric seam of my wetsuit to ground. It removed the fabric seam, but left the rubber of the wetsuit, slightly burning my skin and leaving me deaf in one ear for many months. A cave is not a safe place to hide in a thunderstorm - the column of negative ions rising from the damp, cool entrance is a very attractive conduit!
And indirectly once: I was crouched down and had unplugged the TV aerial about 2 inches from the socket when the aerial was hit. It spasmed my legs so much that I hit the wall 14 feet away and dropped down onto the sofa next to my mother. She went deadly white as I asked her what was wrong. I couldn't bluff it out completely though as I struggled to walk for a few weeks as my leg muscles were very sore.
Under a tree is also not safe. One day myself and farmer friend flat-out crawled up a hill to try and scare his sheep away from a tree before an impending thunderstorm made its way across the valley. We were about 100 yards away when the lightning struck and 26 sheep just silently fell over dead. It raised our hair and it hadn't even started raining at that point! He was very happy I had been so paranoid about the lightning to insist we crawled.
>I had been so paranoid about the lightning to insist we crawled.
That's what killed the sheep. Front and back legs 0.5m apart and both connected to ground, strike creates electric field in ground, legs = potential difference = current through the sheep's body.
If you expect a close by stroke you are supposed to crouch down but only have your feet in contact with the ground and close together.
Did you actually crawl or more like hunch down still on 2 legs only? Keeping low is good but laying down is not good when lots of current flows in the ground. All those sheep were probably killed because they have 4 legs so ground current could pass their hearts. For humans that ground current usually don't reach the heart. Or so I have believed.
I work at a school. I had been explaining the reasons behind having fibre between buildings, even if they were small local runs of only a few feet, especially if the electrical phases between those buildings could be different (now or in the future!). Pretty much, everyone ignored me because the cabling had been in place for years and they didn't see it was worth changing it.
One night, a *huge* tree that is on the site was hit by lightning. It coursed down the tree, found some aerial cables including the cable that ran between a wooden maintenance shed and a permanent building... blew the telephone in the shed into smithereens. The other way, it entered the building and damaged a 48-port switch (which I still have to this day... the middle 24 ports are absolutely dead, and some of the others won't give PoE but everything else works, including the cloud management... we swapped it out and it's now our "test bench" switch).
From the building, it also managed to find some random and exotic bits of hardware, another telephone line that went through the air to some staff accommodation a hundred metres away, blew that up, took out a DSL router and a computer connected to it (not just the PSU, but the whole machine).
However, that same switch also ran a fibre back to the next building where several dozen machines and other critical pieces of equipment were all copper-cabled, not to mention several dozen phone lines, connected to all kinds of electrical equipment, all underneath where the boarding pupils lived. Not a dicky-bird, because the power couldn't get down the fibre. Everything else just stayed up. Fortunately, that building was only fibre all the way out to any other building.
And, again fortunately, I had the sense to run not just fibre between buildings, but also fibre between distant buildings (so if A is connected to B is connected to C, via fibre and switches at each, then I also connected A directly to C with more fibre so that when B was offline A and C could still talk). And then also connecting C to D and D back to A so that STP could do its job and provide a redundant route.
Basically, the fried equipment was more than enough to potentially start a fire in three separate buildings, but luckily didn't. The network just saw a switch go partly offline and routed around everything else. And from then on, every connection that went through open-air or the ground was changed for fibre.
When I were a wee trainee programmer, I was sent on training course in another city (this is the IT angle) , and was on the phone to my then fiancee (we were married 2 weeks later) and we were , well, yes, having a NSFW conversation, when an almighty bang came down the line & the Mrs screamed & hung up (get your mind back in the gutter) .
Some fool had tried to blow up the Family Court in Parramatta ( https://en.wikipedia.org/wiki/Family_Court_of_Australia_attacks ) and we had a unit in the closest street just across the Parramatta River (100-200m as the crow flies) from the then courthouse (close to the ferry terminal for those who know the area) , two of our windows were cracked.
Whilst on the phone to a user, I heard a massive bang through the window before the line went dead. Then another flash and bang. The user's building had been hit by lightning twice at ground level... Over the next day, we observed that the strikes wiped out about 500 PCs, 30 switches, various IP phones and mobile devices hooked up for charging. Fortunately we were in the middle of several upgrades so there was replacement hardware at hand for some.
On another occasion, I was talking to a user who calmly stated that he was going into anaphylactic shock and could I phone one of his colleagues. Thankfully the user was a medic working in a building full of medics.
A friend of mine managed to have a sub arachnid stroke (apparently one of the worst types) at a hotel holding a conference on stroke medicine with several of the world's leading experts on sub arachnid strokes. It was a family trip, and two of her children are GPs (and were in the room with her), so she ended up getting the swiftest, most qualified medical care possible.
A "sub arachnid stroke" caused by a trapdoor spider? Subarachnoid hemorhage
I Was Technical Support Manager at an east midlands county council when the county was hit by a huge thunderstorm, all 6 of our main PABX's and almost every x.25 node was hit and a serious number of PC's were damaged as well.
We'd just bought a load of x.25 switches in preparation for an network expansion and luckily all the PC's had two serial ports. My team somehow managed to get all our equipment replaced in 48 hours and get the network back up, we had to swap the lead to several hundred PC's to use the functioning serial port. Not an easy job in a very large rural county. At the same time BT were working at getting a phone service working, whilst engineers were replacing damaged cards at the Police HQ, then the major hospitals another engineer was working on our PABX's to move extensions around so that the most urgent numbers could make and receive calls. Whilst we managed to return to a normalish service is 48 hours we were clearing up for several months afterwards. during the first 48 hours we lost track of where x.25 equipment was as we swapped damaged switches between sites (e.g. a 48 port switch with 20 working ports replaced a burnt out 12 port switch as we didn't have enough new spares to replace everything damaged at the time), w and we had to purchase and replace over 300 pc's as the insurance company wanted to write the damaged devises off immediately. We also had to schedule PABX downtime windows as the damaged cards were swapped out for repaired cards, due to the large number of cards affected we didn't dare change them all at once. After all that I then had an 'adverse' audit report complaining about my poor asset management processes. I must admit that did make me lose my temper as the team had done such a fantastic job. I ended up having a fight with a senior auditor who claimed that we'd 'lost' £250,000 worth of x.25 equipment when we could show them a working network a pile of written off switches and repair orders for the salvageable equipment which was away at the equipment provider. In the end we had actually discarded a couple of destroyed switches on remote sites where the chassis was so burned it was obviously irreparable. Sensibly site staff had taken out the smelly burned mess and dumped it in a skip, not exactly a normal process but the correct action in an emergency. The divine being icon is for my team who worked their collective asses off to get things back on the air including having to visit some very remote sites several times as kit damaged in the strikes but not replaced at the time failed completely later.
AS an IT techie working for a large mainframe supplier I had several 'interesting' experiences on MOD and Police sites
During a black alert for IRA activities I was banned from taking my car on-site at one base. I was directed down a dark lane to a patch of wasteland on the outside of 'the fence' I noticed that on the inside of the fence there was nothing but empty space. Walking back through security I confirmed my worst fears, the 'car park' was deliberately sited there so if a car bomb went off the site wouldn't suffer any damage. The Guard on the gate reminded me to look for suspect devices before starting the engine and asked if I had a torch and 'mirror on a stick' when I said no he just smirked and let me in. Returning to the car at at 11 pm I was genuinely worried but with no torch there was little I could do but pull up my big boy pants get in the car and turn the key. I was there for several weeks working very long hours and never did get the chance to buy the torch and mirror, bu as I would have had no idea what to look for anyway. Its amazing what you get used to.
Fast forward a couple of decades and I started work for the MOD in Germany a week after 911. Waiting in line at security to fly back the first week was genuinely frightening, there was obviously a very high alert status, they had turned the sensitivity on the hand held metal detectors so low they were going off for most passengers and it was taking 3 minutes to process each of us. On top of that there was a squad of very young looking German soldiers on the other side of security holding machine guns with their white knuckled fingers on the trigger. After a few weeks of using weekly hire cars I was persuaded to take a fleet car you can imagine how delighted I was to be presented with a British Racing Green rover with British Forces Germany number plates. The only thing missing was a bulls-eye on the roof. When a German driver wrote of the rover driving through me stopped at a traffic light I was actually relieved and thought I'd be back in a civilian hire car, When they delivered the new car I was astounded to find it was a duplicate of the first.
NATO HQ in Belgium, back in the days of the IRA and RAF we had unmarked civilian cars.
However somebody had a deal with a local dealer so we had identical white merc salons, but this subtle camouflage was offset by the row of brightly coloured NATO parking and security decals almost filling the windscreen .
So, once upon a time, as a senior engineer in charge of a NOC, I needed to call our sister operation in Texas to check on the progress of an issue. I called the NOC and it was swiftly answered.
"Hi, this is Graham speaking, how may I" and then there was a loud bang. The line went silent.
"Hello?" I said. Nothing in reply.
"Are you still there?" I could hear the usual noise from server fans and AC, but there was still no reply. What had happened? Was my colleague injured?
I asked an underling to go see if he could call the NOC from a different phone. I started leafing through my contacts for my opposite number in the States. Panic started to set in. Had i just heard the final moments of an engineer?
"......help you today?"
"Err, Graham, are you ok?"
"Of course! Everything's good" loud bang. Silence.
....
....
"here! How can i help?"
Turns out, Graham suffers from narcolepsy.
I once worked for TIME computers in the repair section. My colleague had a double PRNE (previous repair not effective) on his desk for a faulty modem that worked fine when testing.
If you released a double PRNE back to the customer and it didn't work you were for the high jump.
Working components would not be exchanged by the parts quartermasters. Blaming customer is not an option, so he was stuck.
So, his line manager suggested he short out a couple of contacts to pop a couple of capacitors on the board.
Next thing, BANG, cloud of smoke, small motherboard fire, evacuation.
.... bloody odd shaped power supplies in the smaller TIME and TINY systems.
Hated those machines turning up at Special Reserve, was always the bleeding power supply (We just had the standard size ATX Power Supplies and stupidly huge copper heatsinks) had blown just after going out of warranty.
One of our users once decided to be clever, and set a BIOS password on their laptop...which they promptly forgot. After trying a variety of different solutions, in the end my boss took the motherboard, and shorted a 9V battery all over it.
Motherboard duly fried, I rang it in for a warranty replacement. Thanks Dell!
I was in the little machine room I habituated (back in the day) when an HP engineer was fitting a replacement PSU to our HP3000 Series III. I was just checking the 50Mb drives (washing machine size) when the engineer powered up the new PSU that he'd had flown in from the USA. He said afterwards that I appeared to teleport past the drives, mostly because he'd forgotten to switch over to 220V and a Series III PSU was a big. meaty beast to go POP...
I liked the HP3000. I have Series 39 running MPE V that I rescued from being thrown away. Not quite the full rack a Series III was. Whopping 2MB of memory, I really liked SPL. It was well documented and nothing was off limits (even if you had to resort to inline assembly for some things).
The embedded Image/3000 database was actually pretty good (for its time anyway).
I woudn't mind a 3000/XL, but they don't tend to crop up that often. Given you can convert HP3000 9x9 to a HP9000 K-class, it should be possible to do the reverse. Maybe if I come across MPE/XL distribution, I'll try that.
Well we still use Pagers for On-call staff. Why? Because a pager only goes off if it's really meant to.
We used to hand out mobiles, but after a few times of staff being woken by Spam SMS or "Windows support" calls at silly-o'clock, we decided that pagers were much better.
I was DCM for a Local Authority in the UK "There's Lovely".
We had bought a new UPS - but we think it was being overloaded and actually went 'pop' with a spark when in use.
Result - no power to the DC.
I call the manufacturers and they suggest that I put it into bypass mode...
this involved cutting the zip-tie on the middle power handle ("cut the red wire, not the blue wire" went through my head as I squatted with a pair of cutters).
I cut the tie and removed it and gave the bypass switch a ¼ turn
"*** BANG ***" - I leapt so high that I think I banged my head on the ceiling and poo-ed my pants (metaphorically - but it was close).
The UPS was fine - my "friends and colleagues" had arranged that my operator was standing behind me with a metal serving tray and a rubber mallet(!?), so that, at the moment of switchover, he whacked the tray.
Anyway, I only received 5 years "suspended" for justifiable homicide :-/
thanks for listening DPM/DCM/RCT
My brother (sadly no longer with us) was a tinkerer. He would spend all his life taking things apart, putting them back together, and putting parts unrelated together to created Frankenstein machines. He seemed to know just how things worked before he had any formal training and this was well before the internet. He did win an inventors competition but making a remotely activated light up dog harness from some string and an old VHS recorder.
Where did this ability and curiosity start? I can't remember - he was always like it but one of the earliest examples was this...
The family were sat down to watch some TV - this would have been the early 80s. I would have been 12 and my brother 8. He was upstairs in his room tinkering as usual. After a while my Mum just mentioned that we'd not seen him for a while and as if on cue from behind the chair in the corner there was a loud, sudden phut! noise and a light as bright as the sun. Then the TV and all the house went dark.
My dad rushed to the chair to be met by my brother, in a bit of a daze and blind, holding a bulb from a torch in his hand to which he had soldered two wires, which he had plugged directly into the wall socket!. Thankfully the temporary blindness only lasted a couple of hours and he didn't actually manage to electrocute himself....
I do miss him so - the crazy fool.
My late father (born in the 19th century) was old school when it came to electrical wiring. To join two lengths of flex, the bare ends, stripped with teeth ( a habit it took me years to kick) were twisted together and folded back in opposite directions along the flex. Then the whole join was wrapped in what he called 'electricians tape' - a sort of cloth based tape soaked in a kind of black tarry goo. This seemed to work OK and was industry standard around our house even after I , as a curious 5 year old pulled one of these joins apart while trying to figure out how the 'wireless' worked. The ensuing flash and bang surprised but enthralled me.
The rest of the family were horrified, but strangely I have never been afraid of electricity since.
I was walking through an assembly area for banking controllers back in the early 80's, these machines had several pint pot 1 farad capacitors on the power supply rails, when I saw a test technician take a dive off his stool and away from the freshly assembled machine he had just turned on. A second later and there was an almighty flash and bang as the power supply exploded.
After checking that he was OK I asked him how he knew it was going to explode, and he told me that although rare this was not they first one the line had experienced and that they were taught to listen to the high pitch whistle the supply made as it powered up - and if it did not sound normal then get out of the way bl**dy fast.
Nowadays H&S would have a hissy fit, but then..
...go out to a GP Surgery who, for some reason (was still studying I think), had forgotten what the voltage switch did on the PSU. So switched it to 115v to see what it did. Then turned the PC on.
BANG!
A staff member came running to him to ask what had happened. He made up an excused and got it replaced :)
User did that - Expected result (BANG for those that haven't worked out the chain of events in this thread by now).
ReplacedPSU
Trashed the MBR so badly that the HDD was put aside, data transfer to new OS & HDD & then once working, imaged back to the original HDD to reduce the massive repair bill.
Was in the lab, prepping for a trip, when an old-style lithium battery decided to vent on me (this must have been around 1991).
Had to evacuate the lab, call security, the whole shebang. Meanwhile, I'm supposed to get on a plane the next morning, and I was only half done. I don't remember how I finished the prep, but somehow managed it. But it wasn't fun.
...watched while a Data Center UPS (size of a large freezer) w/ batteries simply run out of power (due to Maintenance Dept. error), and the entire Data Center was plunged into (crickets chirping) silence ... the next sound heard (from me) was a blood curdling scream for the site Senior Network Engineer.
When Dad was a lad finishing off his Mechanical Engineering degree, he had a course with some of the Electrical Engineering folks working on some project or another. There was a long bench along one wall, and one of the EE's was working on a project at said bench. Lots of wires, lots of expensive looking components, etc. So Dad being the practical joker that he is, manages to talk one of his buddies in on a prank. they run a thin length of tubing from the back of the bench out a nearby window, and Dad has set himself up with the other end of the tubing and a lit cigarette. When said EE flipped on the power supply to his project, Dad's friend signaled him, and he began to blow smoke through the tubing. Cue wisps of smoke seeming to come from the EE's project. Scramble, cut power, signal, and Dad quits blowing smoke. EE proceeds to start tracing wires, examining components, etc. Satisfied that his project wasn't going up in smoke, he flipped on the power supply. Cue the signal, cue the smoke. This went on for 5 or 6 iterations before enough smoke wafted towards the EE that he recognized it as tobacco smoke, not magic smoke. New cue - cue shouting, cursing, threats of grievous bodily harm, anatomically improbable threats, etc....
New DC, not *reaaaaaaly* finished yet. Prod systems, dev systems. Braaaaand spanking new Juniper hardware for networking. DC vanishes off the network. Call network team -- can't get logged into OOB connections. Dispatch network engineer from other site.
Facilities dude (HVAC type, not computer techie) walks into the open complex office, yelling "Who owns the new DC on the third floor?" - The HVAC guys had completed the "network closet" fairly early in the morning. And not connected the AC. And well, there was a "small fire in there now". *Then* the building firealarm goes off.....
The network engineer was already on the highway when we got to tell him the RCA.
Three days to clean that mess up and about two weeks of work by the build team to clean it back up.....
Torg: My lord, the ship appears to be deserted.
Kruge: How can that be? They're hiding!
Torg: Yes, sir. But the bridge seems to be run by computer. It is the only thing speaking.
Kruge: Speaking? Let me hear.
Computer: 9...8...7...6... 5...
Kruge: GET OUT!!! GET OUT OF THERE!!! GET OUT!!!
Computer: 2... 1...
Did I tell the story already where up in Northern Canada DECADES AGO where in a large secretive corporate Data Centre that was nearby a 400 Kilovolt Electrical Transmission Line which had a line going into the facility where we found an INTERESTING WAY to test and ENSURE the quality/validity of the VERY LARGE Fail-over switches during a UPS failover scenario?
For those of you who haven't yet read it in other posts, we who shall remain nameless, stuck a GIANT quarter/half of a pig onto a failover current bar which is generally like a giant fuse (it's like a metre long and two inches in diameter or so). We then tested the failover scenario and blew the pig into NOW VERY WELL DONE many bits and pieces of pork flown as far as many tens of metres away from the original flash point! While the meat actually ON the failover bar/fuse was well charred, the sheer amount of current which was in the MANY kilovolts/high amperage range, superheated the fluids within the pig meat and literally caused a steam explosion to WELL COOK ALL the meat within a mere 1/2 second or so! That much current flashing over WILL COOK EVERYTHING all at once!
After a bit of washing with hot water of the fried pork slabs that were blown well up into the air many metres, we got down to adding some spices and sauces and then enjoyed the fastest-cooked pork roast dinner ever made! Quite Delicious I must say! AND it wasn't the first time we did that current surge/failover test with slabs of various kinds of meat! Beef, Pork, Turkey, Chickens, Goat, even various fruits such as Pineapple, Watermelon and even Bread Dough! It ALL got cooked in less than a second! It was fun while it lasted!
We were quite the stupid but fun bunch of Specialty IT Services personnel! We entertained ourselves very well indeed!
AND I must admit that the FLASH-COOKED food tasted quite wonderful!
.
On that fateful morning I called Amex about a card problem - then I heard a boom and lot of screaming - the lady on the phone said: I don’t know what that was, the whole building shook. Let’s just complete this - Then she wished me a nice day. To this day I don’t know whether she survived and got out of the building.
I was sitting at my desk at Sun on Fabian Avenue in Palo Alto. The network alarms for equipment on top of the North Tower had started shrieking (sonalerts) a little over an hour earlier. I already knew that an airliner had hit WTC 1 ... Time was compressing for me, so my personal time-sense doesn't track the actual time of events.
I was talking to a compadre in the Sun offices in WTC 2 over a private line[0] about the problem (Sun had offices on floors 25 and 26). He said "What the fu ...", and the line went dead. Simultaneously, my network started shrieking again as the alarms went off. I hit the "kill the noise" button again & eyeballed the network ... only to discover that I could no longer see any of the equipment on the roof of the south tower. I echoed the "what the fuck?!!!??" sentiment ...
I reconfigured my telephone[1] to connect thru' the basement of WTC 2, and called my compadre. He allowed as to how rumor had it that a second airliner had hit the building. Again, I exclaimed "WTF??? Get the hell OUT! And take the stairs, not the elevators ... And make sure the folks who have issues get help getting out. NOW!"[2] ... His reply was "we're already on it" ... and the phone again went dead. They all got out[3].
[0] Cell phones weren't as ubiquitous then as they are now ... However, we had them. Unfortunately the cellular network was down at his end, for what should be obvious reasons.
[1] Was on an NET IDNX based network that I had admin rights to. I wasn't a Sun employee, I was a private contractor, acting as a NET liaison between Sun and IBM.
[2] I'm an ex-volunteer firefighter ... funny how training helps in emergencies.
[3] Sun employee Philip Rosenzweig was aboard Flight 11 ... RIP, buddy.
I was watching the news on 9-11 when I got paged in to work. Performance from my company's internal network to the overloaded CNN website was poor. We'd planned to install cache engines to improve general web performance. Our gear was ready to go but we had been having trouble getting approval to execute the change.
I ended up executing the cache engine go-live under a "poor performance" P1 during business hours on 9-11.
It didn't have to be a large capacitor to produce a worthwhile effect. I had a work colleague (can't now say friend) who was a draughtsman, who used an old-style drawing board. We always tried to get one up on each other, and my favourite was to wire up a small cap, say 10uF or so and reverse connect it to a variable PSU on the other other side of a dividing partition. The cap was secreted on the back of the drawing board and wiring concealed.
Method: Turn the current control down to zero, voltage up to say 20v and then turn the current up to max. After a couple of seconds the resultant bang, cloud of smoke and accompanying shout of dismay livened up many a boring morning. My colleague became so paranoid he used to check for hidden wiring every time he'd been away from the board - to help him I used to just wrap a short length of wire at random round one of the supports to unnerve him. Eventually this entertainment palled - to be replaced by putting a small air-operated diaphragm pump with the exhaust removed in the bottom of his waste bin and covering it with discarded coffee cups and paper. Turn on the air supply and the resulting roar of the pump and fountain of detritus... well
I am still ashamed of myself...
"Reminds me of an old "colleage" the introduced us to LEDs and 120V."
Reminds me of a story my late father in law (electronics engineer, radio ham and all-round boffin) told me. In the early 1950s, when he was working at a large British electronics business, they'd been provided with a few of these new-fangled transistors - replacements for valves/tubes. So they gave them to one of the lab technicians. After connecting a few to a 150 V supply he reported that these things were totally useless and didn't do anything :)
About ten years ago, shortly before he died, we had a lot of fun going through his stock of by now vintage electronic components. 1960s components are much more photogenic than modern ones. That was also the time when you could look at a schematic or assembly and within a few seconds make an educated guess as to what it did. Nowadays it's all just a collection of black blobs - could do anything. Apologies, strongly disliking nostalgia doesn't mean I don't occasionally succumb to it (esp. after my second glass of wine).
Got back from dinner in Tulum after a day cave diving.
One of our party had swopped batteries on their charger just before we went out. EXCEPT.....
Instead of plugging flat battery into charger flat was connected tp freshly charged unit.
Who says you can' make a battery pack look like a 200 year old church candle. Would have been hours of work for a skilled dribbler. [*]
Smell was interesting too!
Dave
[*] I feel a TP ref appropriate.
Some years ago I worked at a well known daily newspaper that had offices on City Road in London. The computer room was on the ground floor with big floor to ceiling windows looking out on a cemetery. On the other side of the cemetery was an Army barracks.
Some time before I joined, my predecessor was on the phone to his boss, who was somewhere outside London. Boss heard a loud bang, followed by total silence which went on for a long time.
The IRA had gone for the barracks, and blown in the windows in the computer room. Luckily there were heavy vertical blinds that were closed, so containing most of the flying glass.
Quite *why* they put the entire production system for the paper in such a vulnerable place (having previously had threats from the IRA themselves) is not known.
One of my responsibilities at a site, I would do the programming of variable frequency drive replacement units before shipping to customers.
This involved pulling the case, hooking up the 3-phase power, switching the unit on and finally sending a small configuration file from a laptop.
On one occasion a VFD unit was on the floor of the shipping dept while I was standing, looking down at it as I switched on the power.
I noticed a red LED had lit up that had never happened before.
Wondering what that could be, I turned around to switch off the power.
There was a loud bang just before I was able to break the connection.
When I tuned back around I saw a mushroom cloud where my head had been just a few seconds earlier.
I could see that 3 large capacitors had been vaporized.
As it turns out, a 220V VFD unit had been stocked in a 440V box.
Lucky my head is still in tact (mostly) and learned a valuable lesson for me.
I've never assumed a component size from it's packaging/description ever again.
A few years ago I was working with a subject matter expert in the UK. His spelling and writing style were a bit idiosyncratic but I got used to that after while. One evening I got a very strange e-mail from him which didn't seem to make sense. Gave me quite a fright as I got the impression he might have had a stroke or something. Didn't have a phone number so couldn't call him to see if he was OK. Half an hour later I got another e-mail from him - apologising for having sent me an e-mail he wrote using voice recognition, without checking it :)
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