back to article A time when cabling was not so much 'structured' than 'survival of the fittest'

The right tool for the job is a motto to live by. But in this week's Who, Me? a Register reader recalls what happens when the wrong tool is used by a right tool. Today's story, from "Keith", takes us back to the heady days of the 1990s and the expensive funnelling of market data to customers keen to maintain their edge. The …

  1. Anonymous Coward
    Anonymous Coward

    Something similar!

    Someone putting up a bracket in the machine room for something - drilled through the drywall perfectly between 2 wires, shorted them out and the whole comms room went dark (which happened to be the room on the other side of the wall).

    Fun times!

    1. Anonymous Coward
      Anonymous Coward

      Don't mix power tools and alcohol

      My Dad managed to do that once. He was drunk, and my Mum was upset about a mirror not having been put up. She really should have saved that outburst till later. He decided this was the perfect time to embark on such a task, and proceeded to drill into the wall, hitting those two wires with astonishing precision. The drill was plugged into the very socket those wires were powering, so there was a loud bang, followed by purple smoke. Mercifully he wasn't hurt, and thankfully this sort of thing was not a common occurrence in my house.

      1. Arthur the cat Silver badge

        Re: Don't mix power tools and alcohol

        Given the way electric drills always seem able to find hidden infrastructure with pin point accuracy, I'm surprised the military haven't funded research into the phenomenon. It's certainly better than any targetting technology the military actually uses for weapons.

        1. ShadowSystems

          Re: Don't mix power tools and alcohol

          The military should have done some serious testing on my dad before he died. That man could locate every wire in the place with nanometer precision, but only after he'd grabbed the wrong power tool for the job. Need a hammer? He'd grab a power auger & !ZAP! blow all the breakers in the state. It got so bad that mom flat out told him "If you trip the breaker you'd better start running before I can target your ass with a nail gun."

          Or maybe the military could examine her instead, she could target hitting me with a thrown shoe for misbehaving from across the property & thwap me no matter how hard I tried to duck & dodge. =-Jp

        2. KarMann Silver badge
          Coat

          Re: Don't mix power tools and alcohol

          Yes, when I was watching something recently about some dowsing rod nonsense with my SO, and it was saying that they have a device that supposedly locates underground pipes and wires, I naturally had to say 'I know! A backhoe!'

          Then I had to explain/show what a backhoe is, because either they're called something else here in the UK, or she just didn't happen to be familiar with that particular wire-targeting device.

          ETA: Now that I think about it, I believe it was something on a recent ElectroBOOM, which makes it even more relevant to this discussion. He certainly shares that knack with the head of comms & backhoes.

          1. Phil O'Sophical Silver badge

            Re: Don't mix power tools and alcohol

            Backhoes are known in the UK as JCBs, after the name of the best known manufacturer - Joseph Cyril Bamford.

            1. KarMann Silver badge
              Thumb Up

              Re: Don't mix power tools and alcohol

              Ah, I know of JCBs, I've driven past at least one of their plants a few times, but didn't realise the name might be specifically applied to backhoes and their ilk, rather than just any of that yellow construction equipment. Thanks!

              1. Contrex

                Re: Don't mix power tools and alcohol

                If you wanted a term that was not brand-specific, you could say 'digger' or 'excavator', as many equipment hire companies in the UK do.

              2. John Brown (no body) Silver badge

                Re: Don't mix power tools and alcohol

                That specific style is also often known simply as a "digger". ie it has the big wide bucket on the front and the smaller articulated bucket on the back. I'm not sure why it's called a backhoe in the US though as the bucket digger on the back is nothing like any hoe I've ever seen :-)

                1. Paul Hovnanian Silver badge
                  Devil

                  Re: Don't mix power tools and alcohol

                  Nothing like any ho' I've ever seen either.

                2. J.G.Harston Silver badge

                  Re: Don't mix power tools and alcohol

                  I thought a backhoe was specifically the tool on the back of the digger, not the vehicle itself. 'cos it's got a scoop on the front as well as a hoe on the back, and it's attached to the back. Wiki appears to agree with me: "a digging bucket on the end of a two-part articulated arm. It is typically mounted on the back of a tractor or front loader"

                  Edit: ah, and it's *back*hoe as the digging action is backwards towards the vehicle instead of forwards pushing away from the vehicle. As in the term as used in gardening, backhoeing, when you dig towards (backwards) yourself.

                  1. Terry 6 Silver badge

                    Re: Don't mix power tools and alcohol

                    Greg Wallace ( he of Masterchef) was doing his "How it's made" in the factory gig a week or so back at JCB. And they specifically called the digger at the rear of the JCB the backhoe.

                  2. Robert Carnegie Silver badge

                    Re: Don't mix power tools and alcohol

                    Re garden tools... surely you can only pull a hoe to you? I don't think you can hoe fro?

            2. Allan George Dyer Silver badge
              Thumb Up

              Re: Don't mix power tools and alcohol

              @Phil O'Sophical - Thanks for clearing up the mystery of what JCB stands for.

              1. tiggity Silver badge

                Re: Don't mix power tools and alcohol

                Some people think this when they see JCB

                https://www.jcballs.co.uk/

      2. NorthIowan

        Re: Don't mix power tools and alcohol

        Best tool for anyone drilling or nailing into walls. Non-contact AC Voltage detector, I like the adjustable voltage one. You can make it more sensitive for 24 V AC wiring or less sensitive to get a better feel for where a wire is. Never assume it's 100% right, but they are wonderful.

        I first learned about them when I was having my dead dishwasher replaced. The installer used one to test that we had the right breaker turned off. The dishwasher was hard to turn on, so we couldn't just try to turn it on to be sure the power was off.

        1. Anonymous Coward
          Anonymous Coward

          Re: Don't mix power tools and alcohol

          Doesn't work on water pipes though - Don't ask.

        2. Dave314159ggggdffsdds Silver badge

          Re: Don't mix power tools and alcohol

          Those were always largely useless, and are even more so where metal studwork has been installed.

          Very simply, cables should not be fixed in place without being protected by trunking. If you can drill into them, the wiring is not to spec - if they're loose, the drill just pushes them aside. So, if it happens, the one drilled cable is the least of your worries, because the entire building urgently requires a rewire.

          In the UK, commercial buildings have to close pending rectifying work, when that sort of thing is discovered.

    2. big_D Silver badge

      Did that in our new house. I was putting in skirting boards and drilled a hole in the wall in the bedroom, only to short the wires coming up from the ground floor into the first floor, everything went dark!

      Somehow, I managed to just brush the wires or the spinning drill caused enough interference to break the circuit. The drill was still fine and after resetting the breaker, I could carry on, putting the drill back in the hole was fine, but spinning it up caused it to trip again - so not a normal power surge.

      Luckily an electrician friend of the family was there putting in some new plugs and light switches downstairs and he could quickly repair the cables in-situ, without having to break open the whole wall...

      1. John Brown (no body) Silver badge
        Facepalm

        "The drill was still fine and after resetting the breaker, I could carry on, putting the drill back in the hole was fine, but spinning it up caused it to trip again - so not a normal power surge."

        WTF? See icon ----------------->

        For full clarification, you drill a hole, cause a power outage, turn the power back on and do it all over again in same hole? Really? Maybe you ought to have asked your electrician friend to look into it BEFORE you put the drill back into the same hole.

        1. NXM Bronze badge

          Logic dictates ...

          ... that people don't try it again. Bit I've seen loads of occasions when someone, for eg, touches something live, shrieks 'ow!' and then does it again to see if it really was live.

          I've done it myself when brain was offline. Recently I released a gate which acted like a massive spring, bloodied my nose and launched me backwards into a pile of shit ... which I should've done from the /other/ side so it couldn't get me.

          You live and learn, as long as you continue to live.

          1. John Brown (no body) Silver badge

            Re: Logic dictates ...

            "You live and learn, as long as you continue to live."

            ...and the rest get Darwin Awards :-)

            1. lglethal Silver badge
              Trollface

              Re: Logic dictates ...

              You live and learn. Or at least you live...

            2. Sgt_Oddball Silver badge

              Re: Logic dictates ...

              So long as you haven't procreated as I was lead to believe. Only the childless get added since it meant you'd removed yourself from the shallow end of the gene pool.

          2. Rob Daglish Bronze badge

            Re: Logic dictates ...

            Ahem. Yes. A younger, but not necessarily more foolish me once touched a screw in a Tenerife hotel socket that had become live. I wasn’t sure if the tickle was a rough edge on the screw or a genuine electric shock, so I did the only sensible thing - lick the finger and have another go.

            After getting up from the floor, I decided it wasn’t a rough edge on the screw head…

        2. Chris G Silver badge

          "BEFORE you put the drill back into the same hole."

          Check there isn't an old bloke with a beard and Victorian clothes hanging around.

          He mat just be waiting to give you an award, posthumously!

        3. big_D Silver badge

          Given all the other work going on, the first time, I though we had just overloaded the circuit. We'd had about half a dozen outages over the previous few days, due to too many drills, jack hammers etc. being used at the same time.

        4. Paul Hovnanian Silver badge

          Be kind. He's probably in the IT biz. Let's turn it off and back on. And see if it does it again.

          1. RockBurner

            Reproducibility of a phenomenon is the very root of true science.

      2. Old Shoes

        You installed my TV

        I think we have met. You installed my TV!

        Three blokes, very professional, matching company polo shirts. Marched in with the TV and broad smiles. Penciled out the marks on the wall where the bracket would go. Giant power drill to blast into the concrete.

        “Hold on a moment,” I said. This penciled in hole is directly above the power point. “You’re going to hit the cable feeding that power point.”

        “No problem,” the foreman replied. “Circuit breaker.”

        Sure, that’ll save your life, but I’ll have a dead power point and fixing a busted cable inside a solid concrete wall will not be easy. I convinced him to wait long enough for me to find the builder (he was at another unit downstairs) and confirm that the power was not fed from above the fitting.

        A job well done.

    3. DS999 Silver badge

      Was there no conduit?

      Commercial electrical code in the US forbids running wiring through walls without conduit, and I would assume the UK/EU is the same. Or was it plastic smurf tube type conduit (that someone drilling a bit overeagerly might not notice encountering) instead of metal?

      You'd think a "machine room" would use only metallic conduit for anything running behind a wall, but I suppose this was one of those machine rooms that wasn't built as such but repurposed from a meeting room or classroom or something?

      1. John Brown (no body) Silver badge

        Re: Was there no conduit?

        Something built to standards or code at the time is still classed as "safe" and legal up to the point where you are refurbishing or modifying, at which stage it needs to be brought up to current standards/code. But even then, it depends on the work you are doing as to whether you need to rip everything out or just make sure the new additions/changes are up to current standards. When I had some electrical work done 5 or 6 years ago I was legally obliged to replace the old fuse box with wire fuses with a modern "consumer unit" with trip switches, but not all the existing wiring, that just had to be tested top make sure it was safe, no shorts or earth leakage etc.

        1. Potty Professor Bronze badge
          Facepalm

          Re: Was there no conduit?

          I recently built a shed and wired up the lights and power sockets. I put a new Distribution Board alongside the existing one in the garage, but was not allowed to connect it to the meter tails myself. My Landlords sent their electrician to check my work and connect it up. So now I have the old plastic DB for the house and garage, with the new steel DB adjacent to it for the new installation.

        2. Dave314159ggggdffsdds Silver badge

          Re: Was there no conduit?

          "Something built to standards or code at the time is still classed as "safe" and legal up to the point where you are refurbishing or modifying"

          Sort of. Sometimes it's only that no-one knows, and as soon as it is discovered, the building has to be closed until it can be fixed. If an installation is dangerous, there are no grandfather clauses that protect the owners from prosecution.

          As I explained above, it should not be possible to drill into cabling. If it is possible, it's a serious safety issue. Immediately turn off the power at the main breaker, evacuate the building, everyone can WFH until the building is entirely rewired. And yes, I have done that in a major office building in the West End, fairly recently (although pre covid).

      2. Anonymous Coward
        Anonymous Coward

        Re: Was there no conduit?

        "Code forbids ___": famous last words of many a worker who forgets that "built to code" in the US can mean "inspector was paid off" instead of "safe-ish".

        1. Gene Cash Silver badge

          Re: Was there no conduit?

          Look up NEMA 10-30 standard plugs in the US that don't have a dedicated ground pin for 220v, because the appliance companies argued it would be too expensive.

          The inspectors got paid off at the very highest level. They're no longer code, but I have one for my dryer.

          1. Allan George Dyer Silver badge
            WTF?

            Re: Was there no conduit?

            @Gene Cash - I'm very glad I've never met a NEMA 10-30. Before today, I would have assumed a 3 pin mains plug included an earth connection.

            Were they actively trying to kill people? (see icon)

          2. DS999 Silver badge

            Re: Was there no conduit?

            Those date from when there were also NEMA 1-15 receptacles, and like those have been deprecated for years.

          3. Robert Carnegie Silver badge

            Re: Was there no conduit?

            I see that as of recently, there are enough NEMA 10-30 outlets in home garages for Tesla and compatible suppliers to sell a car charging cord. "Fits most dryer outlets installed in homes built prior to 1997." "Since the 10-30 outlets only have three conductors, the ground and neutral are shared, and both are present on the outlet’s L-shaped slot. Our EV adapter has been designed to route the ground connection from the 10-30 outlet while leaving the neutral alone." (Note, not actually Tesla.) So, what, the L-shaped pin is two-sided??

      3. J.G.Harston Silver badge

        Re: Was there no conduit?

        UK electric regs forbid bashing holes in walls directly above or alongside any outlet, or within (mumble) of horizontal and vertical corners. Similarly, the sparks are required to run cables only within those lines. So, the electrics is all complianty installed, it's the drill-wielder who's operating non-compliantly. *He* is the one who is *required* to assume all verticals and horizontals are forbidden areas and is *required* to not drill through them - even if in reality there is no cable there. See link.

        1. Dave314159ggggdffsdds Silver badge

          Re: Was there no conduit?

          No. That is wrong.

          Cables must be loose - that is, not-fixed in position - or must be protected by trunking. It is not possible to drill into cabling where it is correctly installed* - barring switching drill bits and persisting until you get through the trunking.

          *Well, except right next to sockets, switches, etc, where the cable is held by the socket, switch, etc. But there you can take the faceplate off and see exactly where the cable is, move it aside, and so on.

          There are also rules about how to run cables, but they're belt-and-braces compared to how to _install_ cables.

          If you do manage to drill into cables, it is almost - 99.99%+ - certainly a dodgy installation. Even idiocy of a high degree is rarely enough to manage it in a compliant building.

          1. MarkTriumphant

            Re: Was there no conduit?

            I suspect the person that you replied to is talking about Wiring Regs for home use.

            1. Dave314159ggggdffsdds Silver badge

              Re: Was there no conduit?

              Perhaps. Those are broadly the same as for commercial. The point is that you ought to be able to drill holes pretty much at random without any fear of hitting a wire.

              1. MarkTriumphant

                Re: Was there no conduit?

                Unless they've changed wildly in the last 9 years, I thought that home stuff did not have to be run in metal conduits - lots of plastic options. Thus the restriction on cable placement. Isn't that so any more?

      4. phuzz Silver badge

        Re: Was there no conduit?

        I would assume the UK/EU is the same.

        Our office (including the server room) is in a 150 year old building. It wasn't built with electricity in mind, let alone any kind of 'building code'.

        Still, it looks like most of the electrics were updated in the 1950's, so it's pretty modern really. My electricity supply at home (in a similarly old house) is shielded with tar coated canvas.

  2. Anonymous Coward
    Anonymous Coward

    Guilty as charged

    Decades ago, I was asked to swap a cable round on the back of a server.

    Said server had a LED on the back, which would light if you pressed the matching button on the front, to help identify it when you were round the back.

    I was told to press said button, which I did.... which resulted in a catastrophic power-off. Which idiot designs two buttons next to each other?

    1. Arthur the cat Silver badge

      Re: Guilty as charged

      Which idiot designs two buttons next to each other?

      Potentially there's about 7.7 billion of them.

    2. phuzz Silver badge
      Facepalm

      Re: Guilty as charged

      Last generation (and maybe current gen as well?) HP servers have disk caddies with a big red LED on them.

      I got an alert about a disk failing in a mirrored array on a server, so I went down to swap it. Looking at the server, it had only two disks, one of which had the red light lit up. I assumed that it was an error light, so that was the drive I removed.

      Apparently someone at HP thought it was much more sensible to turn on the light when the drive should not be removed, so I mistakenly pulled out the good drive. Now the machine had one bad drive, and one blank one, so it quite messily halted.

      Fortunately, although I messed up some currently running tasks, once I rebooted the machine with just the good drive in, I could then add the new disk and it happily rebuilt it's mirror.

  3. Version 1.0 Silver badge
    Happy

    Sounds like us (sic)

    A good story El Reg - I've seen this happen too. Messing around with AC power is something that people do not worry about in the USA, 120V is a little itch, not a shock so this story sounds like it might have happened in the US, not the UK. I see people do live wiring all the time over here, putting wires into terminals and tightening screws with a little spark most of the time.

    I remember my first 240V shock in the UK, I was a kid and wet myself when I picked up the box I was working on and my finger went over the back of the power switch. Ouch!!! OK, I need to change my trousers!

    1. Potty Professor Bronze badge
      Boffin

      Re: Sounds like us (sic)

      When my father was posted from University College, London, to University of Louisville in 1963, he caused an uproar when he checked to see if a socket was live by touching one terminal with his finger. All of the medical staff had fits, "You mustn't do that, it'll kill you". "Nah, it's only 110V, it just tickles" was his reply.

      Personally, I used to work for a large electrical manufacturer, we produced equipment for 1100V, 3.6kV, and 7.2Kv, and I was authorised to work on live equipments at all of those voltages. I wasn't authorised for 11kV because that kit was produced at another site, and we didn't have any test sets for that voltage anyway. I still work on live equipment to this day, but the only voltages I touch are 415V or less, but I still take all the precautions I had drummed into me back at GEC.

      1. Allan George Dyer Silver badge
        Alert

        Re: Sounds like us (sic)

        Apparently, my grandfather's preferred method for checking whether the bulb or the fuse had blown was to, while standing on a wooden chair, lick two fingers and put them into the bayonet cap light socket. However, this would have been before UK electricity was standardised on 240V.

    2. Dave K

      Re: Sounds like us (sic)

      Yeah, 240v can be unpleasant. I once got a nasty belt in my parent's old house. We had a hanging ceiling lamp downstairs in the hallway with 3 bulbs in it and one of the bulbs had blown. I changed out the bulb and switched it on. All looked well! I noticed the lamp fitting was swaying back and forth due to my recent work on it, and reached up to steady it. Cue a nasty zap from the fitting which felt like someone had yanked my arm off. Thankfully, no worse damage to me than that.

      Later that evening, we removed the fitting from the ceiling and found that the genius that had fitted it originally had just twisted the bare wires together from the fitting and the house wiring (no connector block, not even some insulating tape around them), then screwed the (metal) fitting of the lamp over the top. Unsurprisingly, one of the cables had come to rest against the light fitting. Result? Every time the light was on, the whole fitting became live.

      1. John Sager

        Re: Sounds like us (sic)

        I did that at the age of two. My grandma had a switch hanging on flex over the bed, which wasn't that uncommon in older properties in those days. They put me down on her bed for a sleep and I just unscrewed the switch & stuck my finger in...

        My other grandma then promptly knitted a cover for her similar switch! I've had several 240v belts since then but not in recent decades. Perhaps I've had wisdom shocked into me!

        1. W.S.Gosset Silver badge
          Happy

          Re: Sounds like us (sic)

          > My other grandma then promptly knitted a cover for her similar switch!

          I am loving the quiet bricoleur genius of this.

          "Haha! That's ridic... ... ... wool's an insulator...

          "And a wide knit with a wide yarn creates and compels an air-gap..."

          Grandma, yet again your homespun traditional skills, routinely eye-rollingly dismissed by the young'uns, have risen to the challenge in protecting your family even in the wildly distanced/disassociated newfangled field of electricity. And challenge not just met, but nailed.

          Sure you could have some proper factory-fitted plastic shield and some proper electrical work. But when you look at this, you know Grandma kept you safe. Which makes it better.

          .

          For some reason an image keeps flicking into my head and I keep laughing:

          PFY walks in to find BOFH completely encapsulated in a whole-body balaclava, like a sealed-off (giant) sock, very woolly and determinedly hand-knitted, with only eye-holes.

          PFY: "What...?"

          BOFH: *muffled* "Granny Sager is henceforth to be regarded as off-limits."

          1. W.S.Gosset Silver badge

            Re: Sounds like us (sic)

            (Weatherwax vibes.)

          2. Doctor Syntax Silver badge

            Re: Sounds like us (sic)

            Perhaps her rationale was that it would stop anyone else unscrewing the switch.

        2. Terry 6 Silver badge

          Re: Sounds like us (sic)

          I did that as a kid. Old enough to want to know how the light switch suspended over my bed worked. Not old enough to know that unscrewing the thing could be a bad experience.

          The switch was a bakelight globe thing, probably about 3cm diameter, that was in two halves with an external push arm and then the live gubbins inside. Easy to unscrew for even a small child.

    3. Anonymous Coward
      Anonymous Coward

      Re: Sounds like us (sic)

      I remember my first 240V shock in the UK

      I got my first experience with 380V when I moved to Belgium and had to disconnect an electric cooker - the plug came apart in my hand and I accidentally brushed over a live contact. I found 240V bad enough, but I was very glad I did this one handed because that didn't half pack a punch, enough to encorage me to not ever doing that again without fully cutting power first..

    4. anothercynic Silver badge

      Re: Sounds like us (sic)

      And then Americans laugh at the Brits having a switch by the socket... "Whyever would you need that?" they say...

      Well, do *you* wanna find out how much fun 240V AC is when you're trying to remove your broken plug from the socket? While it's live? Be my guest! Don't pee yourself or all over the carpet please... it's from the Victorian era.

      You're welcome.

      1. Precordial thump

        Re: Sounds like us (sic)

        That rug really tied the room together.

    5. Anonymous Coward
      Anonymous Coward

      Re: Sounds like us (sic)

      Having had a few 240V belts over the years I now have a distinct aversion to getting a tingle, to the extent I am very reluctant (like bloody won't do it) to even try this missus' TENS machine.

  4. DJV Silver badge

    Screwdrivers in wrong places.

    Not IT related but I've got a couple here:

    1) Back when I was a teenager my second job was an apprentice TV engineer. Poking around in the high voltage areas of a TV with a screwdriver and not a lot of teenage wisdom would occasionally result in accidentally earthing part of said screwdriver's shaft to the chassis while the tip was in contact with something very much NOT at earth potential. The resulting spark would often temporarily spot weld the screwdriver to the chassis! Good job this was back in the valve days as those things were far more resilient to weird voltages being thrown around than the transistorised replacements that had started coming along around the same time.

    2) A few years ago I had a guy out to do the regular yearly service on my gas combi boiler. He'd cleaned everything up and partly re-assembled it and was testing how well the water was heating up before putting the main case back on. At the same time he was looking around for a screwdriver that he'd misplaced. Then he noticed a "slight" irregularity through the small window that gave a view into the burner - he'd found his screwdriver! A hasty disassembly and the screwdriver, whose plastic handle was by now slightly melted, was recovered! The following year he was still proudly using the same screwdriver...

    1. Version 1.0 Silver badge
      Thumb Up

      Re: Screwdrivers in wrong places.

      Ah yes, the old days when, after your first shock, you always remembered to short out the CRT tube before pulling it out to replace it after the CRT heater died. Sure, it was kilo volts stored in the CRT but only a few micro amps.

      1. Patched Out
        Facepalm

        Re: Screwdrivers in wrong places.

        When I was just a teenage nerd, I acquired an old all vacuum tube Dumont oscilloscope along with complete service documentation. One Saturday morning I decided to give it a full service/alignment. Not being totally stupid, I knew I needed to discharge the CRT. However, I basically jumpered a large insulated handle screw driver to the chassis without any kind of limiting resistor to allow the charge to drain off in a controlled manner. As I moved the tip of the screw driver close to the terminal, an enormous spark jumped the gap and made a CRACK sound loud enough to wake the dog upstairs and set it to barking.

      2. Will Godfrey Silver badge
        Unhappy

        Re: Screwdrivers in wrong places.

        Have you noticed the tube manufacturers used to put the anode cap exactly where your thumb lands when you go to pick it up.

      3. Neil Barnes Silver badge

        Re: Screwdrivers in wrong places.

        SOP in BBC engineering was to discharge the CRT. Then do it again, a couple of times... the first time never emptied it completely. The CRT anode on a broadcast monitor often ran in excess of 25kv.

        Before the days of transistors everywhere, the flyback efficiency diodes were glass valves; part of the mandatory safety instructions was to surround that with a lead-glass tube to keep stray x-rays in check...

        1. Mast1

          Re: Screwdrivers in wrong places.

          I was "trained" that there were 3 reactions possible when carrying a replacement CRT and accidentally touching the anode cap:

          (1) Idiot : you drop it immediately below you and shower your legs with imploding glass. (pedant alert: yes it IMplodes: the EXploding is the rebound after the implosion).

          (2) Sensible : as you drop it you throw it as far away as possible so that imploding glass does not shred your legs.

          (3) Macho : you stand there and think "I can take it : what is 15 kV?"

    2. Doctor Syntax Silver badge

      Re: Screwdrivers in wrong places.

      Also back in the days of valves I was working on a PA amplifier. The anodes, at about 350 - 400V IIRC, of the output valves were on the top caps and somebody, for some reason, had cut and resoldered the lead to one of the caps without insulating the joint. Replacing the steel cover without switching off...

      1. Peter Gathercole Silver badge

        Re: Screwdrivers in wrong places.

        My worst experience. HT inverter on a CRT TV.

        A few days ago, I noticed I still have the scar from the HT burn on the back of my hand 45 years on.

        Another still visible scar is from where I was reaching in to replace a tube in a guitar amp, which was to be fair turned off, but the belt from one of the still charged capacitors caused my arm to jerk back, causing me to gash my hand on some of the sharp metalwork.

      2. albegadeep

        Re: Screwdrivers in wrong places.

        A couple workplaces back, there was a small UPS that needed its batteries replaced. But what size batteries? We couldn't shut the system down at the time (that's why it was on UPS!), so I simply removed the side cover, checked the size and count of batteries inside, and went to put the cover back on. Still not sure what exactly went wrong, but the spark was quite impressive.

  5. Chris G Silver badge

    Evolutionary manner

    One place I worked at in the early nineties decided to finally embrace the notiion of a PC on every desk.

    It was a small 4 story building from the thirties and still had the original wiring overlaid with five decades of upgrades and telephony so the general mangler decided that ripping all of the old redundant cables out for a fresh start with the modern age.

    Six weeks later, and a couple of skips the old stuff had been removed the floors and walls reinstated and a start made on the new network, the second day one of the installers discovered an old mains incomer in three phase, with his drill, that tripped the local sub-station due to the bit being welded between two phases.

    The incomer didn't go anywhere, it was just taped up and left in the wall under the stairs.

  6. seven of five

    They had it coming.

    > The work included checking out the devices and power supplies. Not a problem

    > for the 100 or so servers in the ops room and their tidy cabling. It was an

    > altogether different challenge for Keith in the comms room and its less-than-structured

    > approach to cable management, however.

    Unfortunetaly, this is exactly what I have come to expect from comms teams and their racks. Sure, there are offenders in both camps. Tidiest are the mainframe guys. Comms and telephone tend to be on the other end of the spectrum, with the excuse usually being "Oh, we don't have time for that now."

    1. Anonymous Coward
      Anonymous Coward

      Re: They had it coming.

      To be fair, if I hear the stories of the contractors we occasionally get in that could very well be accurate. They're not given much time for a job.

      1. seven of five

        Re: They had it coming.

        Problem is, if you don't have time for it now, you'll have even less time for it later on, when Murphy strikes. Do it right the first time hardly ever comes to bite you. It is just a bit sad for the work invested when plans change and you have to undo it prematurely. It is rather easy to live with that.

        1. Doctor Syntax Silver badge

          Re: They had it coming.

          "you'll have even less time for it later on, when Murphy strikes"

          It works the other way round. That's when you do have time for it.

      2. Terry 6 Silver badge

        Re: They had it coming.

        "They're not given much time for a job"

        There's a whole world of wisdom tied to that. Whenever I find a cock-up in some corporate process, from cleaning to completely rebuilding a school there will always be a point where some fuck witted bean counter has said one of "We need to get that done in n number of days", fewer than the experts have assessed it, or reduced the budget to less than it's possible to complete the work with, or said "We'll find money for that bit later". ( They never fucking well do, though.).

        So you end up with inadequate storage space/cupboard doors that don't quite fit/ the promised and essential electronic locks that weren't installed/network sockets with no computers ( or vice versa), but staff who need to use them and so on and so on.

        1. Fred Daggy Bronze badge
          Terminator

          Re: They had it coming.

          Had that done to me exactly once. Learnt my lesson.

          Q: What are the design requirements?

          - Come up with a spec

          Q: What is the budget?

          - Bean counter produces budget

          Q: Where can you save some money to meet the budget?

          Statement: Can't be done

          Beancounter looks me in eye. I flinch. I live to regret it.

          Now, I look beancounters in the eye and am become death. I know that while the beancounter will be backslapped and rewarded for saving money, the one that will be paying is me. In extra call-outs, user dissatisfaction and general stress.

          NO. THANKS.

    2. swm Silver badge

      Re: They had it coming.

      If you ever saw the connections between incoming cables and the line link frame in a telephone company (in the era of wired phones) where 10,000 twisted pair wires connected cables to the switch you would be amazed. All black and white pairs lying on several shelves. Records are a must in this situation.

      1. Anonymous Coward
        Anonymous Coward

        Re: They had it coming.

        Nah, they have line warblers for that. They set up the signal on one end, and then they start probing the bundles until they find one with the warble sound, and then it's a matter of spliiting bundles in ever smaller portions until they find the exact pair.

        This approach also has the benefit of totally ignoring any erroneous or not updated records, plus it makes zero assumptions.

        It does what engineers like: it works under pretty much any circumstance.

    3. Norman Nescio Silver badge

      Re: They had it coming.

      > The work included checking out the devices and power supplies. Not a problem

      > for the 100 or so servers in the ops room and their tidy cabling. It was an

      > altogether different challenge for Keith in the comms room and its less-than-structured

      > approach to cable management, however.

      Unfortunetaly, this is exactly what I have come to expect from comms teams and their racks. Sure, there are offenders in both camps. Tidiest are the mainframe guys. Comms and telephone tend to be on the other end of the spectrum, with the excuse usually being "Oh, we don't have time for that now."

      Not sure I completely agree with that.

      Datacomms guys want to run a new bit of twisted pair line under raised floor of datacentre to carry muxed character-based terminal traffic (Datacentre has IBM mainframe clone plus lots of VAX equipment). Tile is pulled.

      I'd swear it was seething like Medusa's hairdo. The floorspace was completely stuffed with bus-and-tag cables. The very nice raised cable trays that held the 10baseT Ethernet and muxed terminal cables were completely covered by an overlay of piles of bus-and-tag cables laid diagonally across the cable tray runs. The datacomms manager was 'unhappy' that his nicely planned and executed cable layout had been completely stuffed by the mainframe installers. A cable must have been disturbed when the tile was pulled, as when the tile was put back, it actually sat slightly proud, resting on the cables.

      The tmux cable ended up being partially routed around the walls, to avoid the chaos underfloor. I'm not sure if it was ever completely sorted out. The datacomms manager's teams' wiring was always extraordinarily neat, so I'm sure the mainframe installation was done without his team's involvement..

      As for telephone/telecomms installers, I have a story about that which I might share if I get the time.

      1. Norman Nescio Silver badge

        Re: They had it coming.

        Apologies for the braino, that's 10base5, not 10baseT. I was thinking Thicknet=T. It's been a long time* since I used it.

        One of the many reasons the datacomms manager was 'unhappy' was that dumping the bus-and-tag cables on top of the 10base5 cables could have disturbed the 'vampire' connectors, which would not be fun to sort out. In fact, thinking about it, I think that is just what happened, as I distinctly remember helping the comms guys dig their way through a pile of bus-and-tag cables to get to a tap - but not on the day of the attempted mux cable installation.

        *Ouch. 35 years, give or take.

      2. Hazmoid

        Re: They had it coming.

        I worked for a Government department many years ago ( so long ago that the department has split and reformed twice since then) however they had a large data centre with raised floors from the days when they ran multiple VAX systems. The cost to rip out the data centre walls and resize when they went Banyan Vines and then Windows servers was not something they wanted to pay, so the room remained pretty much empty except for a single rack of servers in one corner. When the Vaxes were finally removed, the systems manager decided it was time to clean up the under floor. We pulled out 3 utility truck loads of cables that went to the recyclers.

        The good thing was that the room had dedicated airconditioning, so I moved my desk in there, and the only people who could access the room were IT staff :)

      3. JWLong Bronze badge

        Re: They had it coming.

        https://www.pinterest.com/kokandre3/electricians-nightmare/

        This is the kind of shit I get to work on.

      4. Peter Gathercole Silver badge

        Re: They had it coming.

        I had to lay some fibrechannel and ethernet cables a few years ago (it's not my primary role, but hey ho). Unfortunately, the person arranging the supply of the cables made a mistake and ordered cables about three times too long, but the timscales on the project were just too tight to go through the process of getting the correct length cables.

        No matter how hard I tried with cable ties and serpentine routing, I could not keep the extra length tidy (especially the fibre, because of the minimum bend radius). As time goes by, every time I look under the floor, I regret not pushing back about the too long cables. It's just a complete mess now.

    4. Jeremy Bresley

      Re: They had it coming.

      You've obviously never seen the work of old union telco guys doing waxed twine lacing. Bundle of wires running all the way across the room and we need to run a couple more, step 1 cut off all the waxed twine all the way down, step 2 run the new cables, step 3 spend hours lacing them all into one nice tight bundle. Beautiful to behold, but velcro wraps were such a massive time saver, it's pretty much a lost art these days.

      1. irrelevant

        Re: They had it coming.

        Bloody hell, I remember that. I was taught how to lace up a wiring loom, 1982, Ferranti Training Center, Moston. When I finished the year there, and moved over to Cheadle, everything was already using plastic cable ties.

  7. Will Godfrey Silver badge
    Unhappy

    I managed to to this with a panel pin

    Putting up a picture hook, tap, tap, tap...Hmmm, why have all the lights gone out?

    It had gone between earth/neutral so it was the main RCD that cut out. The embarrassing thing is it was a cable I'd put in the wall myself some 20 years previously.

    1. John Doe 12

      Re: I managed to to this with a panel pin

      Don't feel bad. I cannot remember things I did 20 months ago - sometimes 20 weeks ago ;-) It's a good sign that you had better things to think about than holding onto where you buried some cable for 20 years!!

      1. Pascal Monett Silver badge
        Coat

        Do you remember what you had for lunch 20 days ago ?

        1. phuzz Silver badge

          The only reason I can remember what I ate for lunch twenty minutes ago, is by burping and getting a re-taste of it.

        2. albegadeep

          Yes, but only because I pack the same thing for lunch every weekday!

    2. Dave314159ggggdffsdds Silver badge

      Re: I managed to to this with a panel pin

      And did you fix the cabling, having discovered your dangerous error?

  8. big_D Silver badge

    Stuck a finger...

    I stuck a finger where it shouldn't matter.

    German (and most European) sockets have an exposed Earth connector, so that plugs are earthed as they are inserted. Sort of the opposite of the UK system of the Earth prong being longer and pushing a blanking plate out of the way for the life and neutral.

    This exposed earth connector is also very handy for earthing yourself when working on delicate electronics. Just connect your earthing strap to the socket. Job's a goodun!

    Anyway, years of no problems grabbing earth connectors. I was standing in my office concentrating on my whiteboard on the other side and I lost myself in thought and felt myself falling forward. I reached behind me and managed to get my thumb on the window ledge and 2 fingers in a power socket, where they touched the earth connector. BANG!

    I got a jolt up my arm, my shoulder was killing me and I was a little shaky. I went to reception to report the incident and called up the technicians. They laughed and said I was imagining things. We then went to my office and they tested the row of sockets. Earth dead, earth dead, earth dead, "see, you imagining things", earth LIVE, "oh f*** what the hell?"

    It also hadn't tripped the breaker, for some reason! They turned off the power to my office, then dismantled the socket and found the electrician (some 10 years earlier) had somehow managed to cross-wire one socket and, in those 10 years, somehow nobody had ever used the socket to plug anything in. Unfortunately, they wouldn't let me plug in my rickety of PC, before they re-wired it.

    I had a lucky escape that day.

    1. DJV Silver badge

      Re: Stuck a finger...

      Back when I was an apprentice TV engineer whenever we had a lot of work on we'd call in a retired engineer to help out. The guy was in his late 60s and, having worked in the trade for donkeys years, he seemed to be completely immune to electric shocks. I once saw him check to see if a ceiling light bulb socket was live by deliberately sticking his fingers in it. "Yep," he said, a few seconds later - so we replaced the bulb.

      1. Anonymous Coward
        Anonymous Coward

        Re: Stuck a finger...

        Back when a student earning a few pounds in a TV shop doing deliveries and repairs, we regularly worked on TVs when live. A screwdriver held about 1/2” from the cap of the line output valve would draw an arc - if it didn’t you knew the fault was in that section (usually the valve or the LOPT). Was seconded to a workshop in a neighbouring town and tried the same trick on a TV with a suspect line output fault. Unfortunately they ran their workshop off an isolating transformer and ELCB - killed all power on the premises. Easily sorted…

        On another occasion (when still a student) I was sent to an office to check why a microfiche reader wasn’t working. First check is for mains power so eased the plug partially out of its socket and put a “mains test” screwdriver on the live pin. A loud bang and whole ring main on that floor went down. I hadn’t noticed, in the dark corner, that the socket had one of those fancy brushed steel covers!

        A third tale, from when I was a toddler. My gran’s house had pre-13A wiring and one of the sockets on the wall beside the tea-table was a co-axial mains affair (never seen one anywhere else and nobody knew what it was for). I poked my finger in (as one does as a toddler): luckily, my finger just shorted live and neutral so the current had a short path across the tip of my finger and no current went through me. A jolt and slight burn.

      2. W.S.Gosset Silver badge

        Re: Stuck a finger...

        Reminds me of the collection of old ICL stories, and one of them was the old chap in the engineering workshop who would (accurately) measure (quite high) voltages across bus bars by hand. Literally.

        1. Bowlers
          Joke

          Re: Stuck a finger...

          Prince Andrew would be able to do that, he dosen't sweat either.

      3. Man inna barrel Bronze badge

        Re: Stuck a finger...

        I had safety testing done on some gear, intended to be used where there is flammable gas. One requirement was that the battery compartment could not be opened without the use of a tool, in order to prevent sparks. The guy at the test lab had fingernails that appeared to be tougher than the screwdriver I used to open the cover. We had to strengthen the plastic a bit. No, the test lab guy did not look anything like Wolverine.

    2. Anonymous Coward
      Anonymous Coward

      Re: Stuck a finger...

      We had this in a building in Malta - at odd moments, the RCD would trip, kicking the office into backup generator power, with the equivalent of an HGV engine rumbling two floors up supplying us with enough juice for systems and airco until we flipped it to live again, only for this to repeat itself hours later.

      After a few weeks of this, electricians began to check every newly installed socket and the very last socket they tested was wired incorrectly (typical). As it was only feeding something small, it apparenly hovered just around the current required to trip the RCD.

      That really was a swine to find.

      1. A.P. Veening Silver badge

        Re: Stuck a finger...

        and the very last socket they tested was wired incorrectly

        Of course it was the very last they tested, after they found it, they stopped testing.

        1. W.S.Gosset Silver badge

          Re: Stuck a finger...

          Yeah that's one of my favourites for expanding young'uns minds, introducing the concepts of rotations & boundings of a problem definition to their toolbox. Which steppingstones into active set definition and (rotating again) useful research critiquing. And into the dry droll delight of CS/mathematical/wisdom jokes...

          When they're just starting to get enough repetition of experience to realise a lot of cliches aren't old people being old but simply statements of common patterns:

          "It's always the last place you look."

          "OMG!! *laughing* That's so TRU-UUUE, Dad always used to say that but it's actually so true!"

          "By definition, actually, if you think about it. Because after you've found it, you're not going to keep looking for it, are you? Because that would be stupid.

          "So you'll ALWAYS find it in the last place you look.

          "...By definition."

          "Heyyyyy..." And there's that flicker moment of startled eyes widening, and that almost-audible >crack< of minds widening, and then there's the disbelieving laughter as they realise they'd been looking at a truism and a joke hidden in plain sight the whole time. And the next generation takes a step forward and you've just saved them some time.

          1. Dave314159ggggdffsdds Silver badge

            Re: Stuck a finger...

            I mean, that's the joke. Who hasn't got it by the age of maybe 8?

            I think the look of dawning enlightenment is when they realise something about you...

            Anyway, the real solution here is to _keep looking after you find it_. That little bit of extra effort means things will not always be in the last place you look, and are now much easier to find.

            1. W.S.Gosset Silver badge

              Re: Stuck a finger...

              > I mean, that's the joke. Who hasn't got it by the age of maybe 8?

              Depends on the person, mate. Not everyone's like you. Most people routinely hear it as a Murphy's Law-like groan about larger life in general. Perhaps 99%, in my experience.

              Different perspective.

              Not everyone's like you.

              Nor "should" they be.

              Nor is any one perspective "ideal". The real world's a damn sight bigger and more complex. Growing/adding-to perspectives, such that you can see more ways of looking at things, well that can't hurt and could help, and I always look out for that same possibility myself for myself.

              Perhaps, so could you?

              >crack<

        2. Woza

          Re: Stuck a finger...

          Why assume there was only one problem?

          1. Anonymous Coward
            Anonymous Coward

            Re: Stuck a finger...

            .. because after that we could stop refilling the generator's diesel tank on the roof?

            Bit of a giveaway. They did check other sockets afterwards, but as the problem only emerged after new power socket bars were installed it made sense to start there and lo, they found something. It was confirmed by jacking in something that drew a bit more power and so tripped the RCD pretty much instantly.

          2. Robert Carnegie Silver badge

            Re: Stuck a finger...

            Another angle on this... Ben Aaronovitch's "Rivers of London" urban-fantasy series combines magic, rather a lot of horrific violence, and what I believe to be a well-informed and maybe even realistic portrayal of ethical and diligent police work at street level. Anyway, several times in the series, the officer we're usually following, Peter Grant, explains to us that he's just found the clue he was looking for - but that you still keep looking for anything else that could be relevant, because that's the job - doing it properly.

            Of course this doesn't really apply to you looking around the house for your car keys, because when you find them, you are reasonably sure that there aren't more sets of car keys that you can usefully find... though, come to think, there are some important keys that I've lost track of. Maybe if I just kept looking, I'd find everything.

  9. chivo243 Silver badge
    Go

    Nothing like a disaster...

    to get your off your ass and after the disaster... As I took on more responsibility, I found lots of things that had been bodged just good enough, and it was as far as installations had gone. I found keeping things neat, and allowing for maintenance was a good balance!

    1. Anonymous Coward
      Anonymous Coward

      Re: Nothing like a disaster...

      @chivo243

      It's a new year so I have upvoted you even though you have spelt "arse" wrong...

      1. Doctor Syntax Silver badge

        Re: Nothing like a disaster...

        He probably can't afford a horse.

        1. W.S.Gosset Silver badge

          Re: Nothing like a disaster...

          Hoss.

          1. John Brown (no body) Silver badge
            Coat

            Re: Nothing like a disaster...

            What's Little Joes big brother got to do with it?

  10. Blackjack Silver badge

    Of course a screwdriver is not enough, you need duck tape too. And a knife, and the whole toolbox and of course reading the darn manual.

    1. Boris the Cockroach Silver badge
      FAIL

      Who the hell reads the manual?

      Anyways... handy tip #1 for a long and happy life

      Never trust a power circuit after telling the apprentice which cable to pull out of the socket....

      oops bit a mistyping there.... long and happy life for your apprentice

      1. Doctor Syntax Silver badge

        Boris, don't you think your turnover of apprentices is a bit on the high side?

        1. J. Cook Silver badge

          I mean, that is why the 'chicken stick' (non contact voltage tester) was invented- saves on the paperwork of getting more apprentices. :D

  11. LordHighFixer
    Boffin

    Its not the voltage...

    Once dropped a wrench (spanner in the uk) while working above a 48V battery bank, used as primary power for the local city telco. Did it bounce and hit the floor, oh no, did it take out the power, or trip a breaker, oh no. As is 'normal' in these cases it dropped perfectly on to the 2 1/4"x4" copper rails running the length of the building. taking quite a notch out of said rails, and turning the wrench in to a puddle of molten globules flying through the air. The batteries and associated equipment didn't even notice.

    Also, back in the day, was disposing of a bunch of retired CRT's, procedure was take to dumpster, and break the nub off the back or the neck to safely pressurize them. Unfortunately I discovered that a CRT can hold quite a charge for a very long time, as I picked one up, and happened to grab on to where the cap would be fitted. Not wanting to drop a very large glass object in the shop, I just stood there as it drained through me. Only a second, kilo-volts at micro-amps, but it was an interesting experience.

    1. W.S.Gosset Silver badge

      Re: Its not the voltage...

      >48V battery bank...turning the wrench in to a puddle

      It's (all the) stories like this that for me instantly recall Edison insisting that AC was dangerous and that (his) DC should be the standard power supply running into every domestic residential home --and how close a thing that was due to him being such a dedicated and active public parasite-- which always trigger a quick cold chill flicker over me for what (the risks/costs of) ordinary life could have been like today, in terms of loss of life. If not for a touch&go historical chance at a tipping point. Which was based on Cost, Achievable-At-The-Time Financial Cost for nexus players, not Consequences for all.

      Look at how many anecdotes-of-jolts just on this thread that we'd never have read because that person's just a forgotten scorched corpse, sadly buried as an unavoidable side-effect of modern life. "Sad, but that's life."

      Cold chill, every time.

      1. Ian Johnston Silver badge

        Re: Its not the voltage...

        DC mains was widely used in the UK until the national grid forced standardisation on AC. I have a 1930 book of Electrical Experiments for Children which tells the youthful reader how to work out whether they have AC or DC mains using a length of flex with a plug at one end and bared wires at the other and a glass of salt water.

        1. Potty Professor Bronze badge
          Childcatcher

          Re: Its not the voltage...

          When my parents moved to a house in east London in the 50s, the supply was 100V DC. Some time later, the London Electricity Board (LEB) announced that they were going to change to 240V AC, and that any DC equipment would be replaced free of charge. My Dad went on an expedition and bought (or stole) every DC motor he could find, and attached them to all of our domestic appliances, the mower, the washing machine, anything that could be motorised, was. One afternoon, as I returned home from school, there was an LEB van outside our house, and a long line of new AC motors along the front hall. The next few weekends were spent changing all the DC motors out for the new AC ones.

    2. vogon00

      Re: Its not the voltage...

      >Once dropped a wrench (spanner in the uk) while working above a 48V battery bank

      I wasn't present for this event, but I did witness the aftermath so I believe the explanation given to me when asking 'What's that metallic staining' is true..

      It seems that at the provincial UK Power station I was visiting (courtesy of Best Mate's father, the head engineer[1] ) someone had been doing some work on the overhead beam crane, which was used to shift parts of the Rolls-Royce Avon turbine and associated generator below it during maintenance....and they dropped the very large spanner (TM) in use into the 'transmission trench', where the generator's direct output bus-bars headed off to the first step-up transformer. Que one bowel-loosening[2] large flash and bang, followed by the sound of the mechanical bits spinning back up to speed after the load imposed by turning said spanner into vaporised chrome-vanadium, plating the concrete walls of the trench for about 6 feet either side of the point of impact.

      One stand-out experience was how they monitored the oil levels remotely - there was a system of pipes between the mechanical stuff and the control room, which fed into old-school clear glass jam-jars (Jam=Jelly for left-pondians) with felt-tip pen marks for 'low','OK', and 'High' oil levels:

      The other stand-out was the cooling arrangement..the turbine and generator were covered with a very large yellow-painted hood that enclosed both, with perspex observation windows, This had a large gas inlet pipe at one end and an egress pipe at the other.. I was very interested in this until my 19-year-old self saw the 'H2' labels, at which point I moved in the general direction of 'away'. I got called a 'wuss' and was told not to worry as hydrogen isn't flammable/explosive as long as it's 98% pure!

      [1] Cracking bloke who taught me loads, sadly taken from us way too early - Cheers, David (G4VXR SK)

      [2] Not the words actually used!

  12. Anonymous Coward
    Anonymous Coward

    Oh

    I remember using a screwdriver to lever EEPROM chips out of their sockets when developing software for SBCs in the early 1980s. Never had a problem until the "pre-production, limited issue" DEC board which I discovered, slightly late, had a resistor or similar located under the EEPROM.

  13. Potemkine! Silver badge

    Have you ever stuck a screwdriver where you shouldn't?

    Yes, but I cannot elaborate ^^

    1. Anonymous Coward
      Anonymous Coward

      Was it chucked into an electric drill at the time? Mine was.

  14. Bertieboy

    Shocks

    A little off topic but still remember an amusing incident regarding a cement factory. Scenario; the kiln is down but due to be re-lit later that night. The daywork Electrical crew were tasked with doing routine maintenance on the starter gear to a fully isolated 3kV induction fan, located several hundred feet away from the kiln floor at the back of the kiln. Cue keen young shift manager (yours truly) who did not want a repeat of the last attempted light-up of this particular kiln where the aforementioned fan motor arced over owing to excessive dust in the motor. Said shift manager dispatches shift electrician (normally lazy bugger) to blow the motor out and check all was well with motor - we all wanted a quiet night. In a completely out of character move, the shift electrician goes over and beyond required duty and decides to megger out the cables as well - the screams of terror from the sparks working on the starter were really quite impressive!

    1. Inventor of the Marmite Laser Silver badge

      Re: Shocks

      I did hear one of our service guys, long ago, bemoaning having to replace several multichannel I/O modules. Apparently the site working grunts had taken it on themselves to do a full on job and Megger out all the I/O wiring they'd put in.

      After the midule hardware had been installed.

      Killed a lot of kit very dead.

      1. Anonymous Coward
        Anonymous Coward

        Re: Shocks

        Megger?

        I'm guessing from context that it means testing the cables in some way?

        1. Mr Humbug

          Re: Shocks

          500V insulation resistance test.

          Megger is a brand of test gear and is used as a verb in the UK (see also hoover)

          1. Anonymous Coward
            Anonymous Coward

            Re: Shocks

            Thanks for your answer Mr Humbug.

            Never heard of it before - and I am a Limey! There again, I'm don't do electrical stuff like that - apart from sort out the mess left behind from PAT testers.....

      2. Ian Johnston Silver badge

        Re: Shocks

        When I was working at <cough> University Engineering Department in the late 80s, a new and keen safety officer decided that all the IT kit in the building needed to have its insulation tested by megger. Every single terminal (kids, ask your parents) in the building was destroyed.

  15. aerogems Bronze badge
    Angel

    Should be: Whew It Wasn't Me

    Based on the story, this installment should be titled "Whew! It wasn't me!" When you investigate an issue and realize that it's someone else who cocked everything up. Even better when that someone else is your boss.

  16. ColinPa Silver badge

    How did that accident happen? Whoops just like that.

    My father told me about someone who cut the end of his finger off putting a steel plate in a guillotine, and managed to the end off his finger (just flesh).

    After the patched him up, someone from management (this was the days before health and safety person) came round to see how he managed to do it.

    Easy he said... and showed the manager - and managed to cut the end of the finger on the other hand!

    1. usbac

      Re: How did that accident happen? Whoops just like that.

      This reminds me of an old joke:

      Three men (a lawyer, a doctor, and an engineer) are all about to be executed for various minor crimes. In this particular country, the guillotine is still used as the only means of punishment.

      The executioner asks "who will go first". The lawyer steps forward. He is asked if he would prefer to face down, or face up? He says that "I want to see my fate coming, so I will face up".

      They close the neck of the lawyer in the guillotine, hoist the blade to the top, and trip the release. The blade comes down with a wooshing sound, then with a thud, it stops just above the lawyers neck. The lawyer shouts to the executioner "Let me out. I've read your laws, and if you try, but fail to execute me, I get to go free!" The executioner confers with the magistrate, and after a few minutes of heated discussions, agrees to set the lawyer free.

      After tinkering with the guillotine for a few minutes, the doctor is asked whether he would like to face up, or face down. He responded that he would also like to be face up. They lock him in the guillotine, hoist the blade, trip the release, and the same thing happens. The blade stops with a loud thud. He tells the executioner "I heard what the lawyer said. You have to let me go free". The executioner annoyed, agrees to free the doctor.

      After more tinkering with the guillotine, the engineer is asked the same question about facing up or facing down. He answers "well, it worked for the lawyer and the doctor, so I will face up". They lock him in, hoist the blade, and just before the executioner trips the release, the engineer yells "wait, I think I see your problem..."

    2. Terry 6 Silver badge

      Re: How did that accident happen? Whoops just like that.

      It's an old joke I heard when I was about 12 ( so >50 years ago).

      1. Ian Johnston Silver badge

        Re: How did that accident happen? Whoops just like that.

        When I first heard it the final candidate was Irish. How the world has changed.

  17. 4mula1

    Several years ago at work a maintenance guy was working inside the electrical cabinet of a machine and learned that an accessory mounted to the machine didn't have it's power controlled by the disconnect switch on the main machine. The power had been shut off to the machine by said disconnect switch and while doing whatever work inside the cabinet he needed to do he managed to touch the long screwdriver he was using to one of the, unbeknownst to him, still live power leads to the accessory and ground. It was only 208V (and just one of the 3 phases) but it's not the voltage that kills, it's the current.

    I was sitting in the office nearby at the time with my back to the production area but heard the loud BZRRT! and saw the flash of light on the wall. Two of us ran out to see if he was okay and he way on his back on the floor. When asked if he was okay he said "Well, I'm not dead since I'm talking to you."

    I don't know if they ever wired the accessory to use the disconnect switch but from that point on everybody knew to double check similar machines for the same condition.

    1. Gene Cash Silver badge

      "If God tells you it's locked out, double check with Jesus, then test it dead yourself."

    2. Sam not the Viking Silver badge

      You need hands....

      I have too many tales of near-misses with electricity, not all mine, but all my screwdrivers are insulated up to the tip.

      To prove to staff that a switchboard is 'dead' I demonstrate by placing my hands on the conductors. You need confidence to do this...... And padlocks for the upstream breakers.

  18. TooOldForThisSh*t

    DOH !

    Back in a previous life (before I invented personal computers - you're welcome) I was tasked with disconnecting & removing a large black and white photo processor in the family photofinishing business. Went to the power distribution panel in the warehouse and carefully shut-off power to the machine. No big deal as the black & white processor was clearly labeled as was the color processor that was right next to it separated by a wall. What could go wrong? Apparently the labels had been switched way back when the equipment as installed. When I got back to the black and white processor I proceeded to disconnect the power lines. BAM! Big spark and me sitting on the floor about 10 feet away. By the time my brain cleared, emergency services had already been called. Oh, it was 220V.

  19. Inventor of the Marmite Laser Silver badge

    Kzzzzrrrrt

    Workplace chum of mine had a previous existence working with some shopfitters. On one job hie had been tasked to drill a hole into the bottom of the display window, carefully avoiding the 440V 3 phase cable underneath which was very clearly shown on the authoritative site drawings.

    Unfortunately the site drawings didn't actually

    reflect reality.

    Apparently he was still smoking as he was stretchered to the ambulance.

  20. Franco Silver badge

    Never taken out a whole rack but did once blow a UPS when changing the battery. APC Smart UPS 1500 where the battery slid in the front, but it had a nasty design flaw where the cable could catch in slots that were cut for ventilation along the sides and slice the insulation. Which it did, shorted and the whole UPS and the brand new battery blew.

    Thankfully being a reputable UPS all I got was a bit of spark blacking on my hand but no actual damage, and our local APC supplier changed the unit free of charge admitting that whilst there wasn't a recall of the units it was a known issue that should never have got through testing.

  21. Anonymous Coward
    Anonymous Coward

    screwdriver wound

    Once, in the end of the 2000s, we were moving kit from one french DC to elsewhere.

    I was with an (excellent) indian colleague, a Sick by the way, and we were trying to unrack a particularly nasty one RU appliance.

    See, the sucker who initially racked it, managed to completely block it in an inappropriate rack so we were struggling (screwdrivers and all), the 2 of us, to get the thing out. Meanwhile, the movers were waiting to move the stuff into the lorry.

    There was a shock and I realized my colleague had his hands covered in blood. Apparently he scratched up his hand badly with the screwdriver. Shit.

    While he was telling me it was OK, I insisted it was not, and drove him out of the DC, called the health security guy, then HR etc ... All were bandaging him, while I was doing the french/english translation.

    Then, much discussion happened about anti-tetanus vaccination. The dude didn't recall he was covered and of course didn't have his papers, left in India.

    After, again, much discussion, HR sent him to a doctor and accompagnied him to get an injection.

    I came back to the darn rack, only to discover the movers grew impatient, and decided to unplug the rest of the kit, some in production. No shutdown. Oh dear.

    It all ended up well, my colleague was fixed, the "production" kit turned up to be used only in the imagination of the developper, so no-one even noticed it was gone.

  22. Ian Johnston Silver badge

    Spike?

    Could some kind person explain how an intruding screwdriver causes a spike? I can see how it might cause a dip (an inverse spike, if you like) by temporarily shorting live to neutral or earth, but I can't for the life of me think how it gets more than the normal voltage down live.

    1. Mast1

      Re: Spike?

      Ie screwdriver causes large current to flow in inductive load (all wiring has some inductance) which is then disconnected promptly by rapidly expanding cloud of vaporising metal. L.dI/dt does the rest.

  23. Anonymous Coward
    Anonymous Coward

    Have you ever...

    ...stuck a screwdriver where you shouldn't? Or tried to recover a configuration located only in the memory of the longest serving member of staff?

    Yes...that's IT in a nutshell.

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