Wearing rings, watches, bracelets or any other metal items while anywhere close to electricity is a mistake many people only make once, regardless of their ability to learn.

Even the non-fatal cases can do things like permanently weld your wedding ring to your flesh and leave a painful injury to remind you for the rest of your life.

I am, coincidentally, expecting delivery of a replacement wedding ring today, having lost my original "somewhere" in the house...

It has been generously sized for this very reason, I like all 10 of my digits the way they are now!

I can't remember right what I was going but I was working on my car and something tickled my wedding ring. Nothing bad because as soon as I felt it I moved it well away.

As you say, you only make the mistake once. Sometimes you can be lucky to tell other people about it. Doesn't always work out that way though.

I posted [1]this here last year in a thread titled Field support chap got married – which took down a mainframe

I can still remember, in the early 80's DEC VAX field service engineers removing their wedding ring before working anywhere near the computer's backplane. Apparently the current available from the power supply could heat the ring to red heat in only a short contact.

[1] https://forums.theregister.com/forum/all/2025/06/09/who_me/#c_5086867

Indeed. I've done a lot of work with car batteries - lead acid - which will red-heat a wedding ring, or indeed a carelessly placed spanner. A couple of weeks ago I was building a 15kWh 50v battery... my ring stayed firmly off my finger, and my watch off my wrist. I hate to thing what the short circuit current might be - but the system is fused at 500A.

I don't know if it still gets used but my grandpa, who tinkered with electrical stuff sometimes/helped invent radar, used to say "it's volts what jolts and amps what kill" and it really stuck with me.

A friend of mine reached behind a large bank of relay racks and managed to get his Rolex watchband across the large 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 ... the X-ray machine 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, over half a century 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 cars, trucks, bikes, boats, etc.

For the record, the power supply was no worse for the wear, and the equipment in the relay racks automatically powered back up as if nothing had happened ... Thank you, Lorain.

Note that the Levis 501 "watch pocket" is the perfect place to park a ring for the duration ... I don't wear any other jewelry, so you're on your own for anything else.

When a high voltage low resistance battery short circuits, then everything becomes a fuse.

Busbars and gold rings do not just melt, they evaporate.

I knew this story sounded familiar. Was wondering if I was having one of them Deja-Vu moments.

I once designed and soldered together an experimental PC board with PC/AT bus with a load of LS-TTL electronics to control the exposure time of a CCD video camera and microscope illumination. Inserting this into one of the lab's image processing stations and switching it on caused a distinct feeling of apprehension. I was half expecting some "KZZEERRT" type noises, some smoke, and the distinct smell of burnt silicon. However, nothing happened, which was a huge relief. I started up the controller program to detect the presence of the new board, and nothing continued to happen, which was less encouraging. I then poured over the design, and checked the documentation of the PC/AT bus. It turned out I had missed a thin line over the ACK pin, i.e. it was logically NOT ACK. Luckily I had a spare NAND gate on one of the 74LS00 chips on the board, and could use that to invert the ACK signal. The board worked flawlessly after that. I soldered together some 6 of them, and each time inserting them into a PC and switching it on made me nervous, but happily no fireworks ensued.

Pored.

I used to work at a board manufacturer and almost every time someone started up a new board, someone would time their walking behind and clapping their hands to induce the maximum panic reaction.

A remember Dr. B (if you are reading, Hi) turning on a 6U board and it showing no activity on the front of the board. I asked him what the orange LED at the back of the board signified - It was VME backplane power pins shorting and glowing!

And how many here have had that jumper ping across a system after a long day? Damn, it's right under the system board. How the bloody hell did it get there? It _shouldn't_ short, but ya can't leave it.

(No interesting story here, I just wanted to use the subject title :D )

There’s rather a lot of electrical stuff under the average drivers car seat these days. Very good for capturing and retaining loose stuff you stow in the footwell behind. I’ve no idea if there’s any airbag stuff under there but I didn’t want to find out.

There will almost certainly be a seatbelt tensioner, which is an explosive charge that pulls the seatbelt receiver down to tighten it in an accident.

There may also be airbag wiring - a lot of cars have side airbags in the seatbacks, but I haven't heard of any airbags in the seat bases.

I haven't heard of any airbags in the seat bases

I think that's more getting into James Bond ejector seat territory perhaps?

As I found out when stuff (nothing important!) stopped working after my new puppy decided the wires looked tasty!

"But I too learned my lesson," he admitted.

Sounds like the lesson here is that one can just blag it, and probably something else will come along to cover your tracks. The [1]dead cat effect if you like.

[1] https://en.wikipedia.org/wiki/Dead_cat_strategy

Many moons ago I worked in hardware maintenance. We had contracts for a county council (no names, no pack drill), and they had a problem with a monitor attached to an old Amstrad PC (the first ones they did). These particular PCs had the PSU for the whole thing buried in the monitor rather than a separate ones for display, CPU etc. One power cable means less mess, right?. Amstrad had obviously learned a lot from their CPC range of home computers.

I turned the monitor on, saw that nothing happened, and went for it. I did the usual of re-solder the joints on the tube neck PCB, checked for dry joints elsewhere, checked a few capacitors, and made sure that the distinctive smell of magic smoke was not present. With the case of the monitor still sat on the floor, I reached to the back of the monitor and pushed the power button.

After a fleeting, well known tingle, all the lights went out in the room I was in. And the un-occupied room next door. The wall sockets weren't working either. It turns out that the tingle was due to my little finger resting across the two solder points of the main fuse in the monitor and throwing the RCD. It turns out that little fingers are amazingly good conductors of 240v AC electricity.

I found my site contact, made my excuses, said I needed to take the monitor to the workshop for repair, and left quickly.

As a follow-up to little fingers being good conductors, I once discharged a different CRT monitor through me by having said small phalange touching the screwdriver I was using to short the tube to earth before dismantling it. That was in the workshop though so no real damage done.

I started in a new job, and to say the server room needed a bit of TLC was an understatement.

I thought a good thing to get started on was to see what was plugged into what UPS and how much current were they drawing.

Most had the nice nice networked management, but one just had the serial port, labelled as a serial port, with the instructions giving the baud flow control etc, you know serial port stuff.

So I plugged in a serial cable, read out the details and disconnected it.

What I didn't know that unless you use the specific APC serial cable, the act of plugging in a serial cable tells the UPS to shut down the outputs, cue a big chunk of servers / switches going off line (yes some had both power plugged into the same UPS I *DID* say it needed some TLC)

Once I found this out I quickly restarted and confessed, fearing the the worst, bringing down servers a few days into my new job.

The outcome? I was taken for a beer after work, the general consensus was that it was F_ing stupid design and there is no way that plugging a standard serial cable into what appears to be and has every indication of being a standard serial connection should do anything except give a serial connection.

That was when I knew I was working with really great guys.

unless you use the specific APC serial cable

I may have a couple of those lying around somewhere, despite the fact we no longer have the APC UPS's that they were used for, but you never know so just in case!

I've learned to never discard any cable, plug, gender changer or adapter that has a DB-9 or DB-25 in at least one end. Some 20+ years ago getting onto the console port of a stray Cisco CSS 11500 load balancer (previously known as Arrowpoint; now known as Obsolete) in our data center to zeroize and dismantle it took me five separate plugs and cables (since our sometimes too diligent DC manager had already kindly removed all cables from the box, including that one super secret pinout console cable we kept for that one remaining unit in the network segment everyone hated), but I got there in the end. The Adapter Cluster(tm) extended at least 10 cm out from the faceplate and required careful balancing on top of my laptop screen not to come apart.

Icon: Mine's the one with the light blue DB-9 to RJ45 cable in the pocket.

I was always fairly careful of rings and wrist watches (especially with metal bands) for this particular reason but had never encountered anyone who had suffered an unfortunate outcome from their jewelery. Even working in the vicinity of cryogenic magnets I always wary of any ferrous material and wondered about relatively non-magnetic stainless steel watch straps and watch cases.

Screwdriver bits falling out of the driver into the electronics caused grief on more than one occasion. Epoxying a proper rare earth magnet into the driver fixed that but then I needed a pair of pliers to change bits.

Tungsten carbide rings were a fad a couple of years ago (may still be) and at the time given the relatively low electrical conductivity of WC (~0.2 μΩ·m) I wondered whether they would be a better bet. At the time they were popular with tradies. I use to joke if they fell into a pool of molten metal their ring would survive. (Aqua regia or HF - possibly not.) At the time the WC rings were all pitch black perhaps with some gold inlay; too close to Vetinari's stygium signet ring. ;)

Regrettably, there are stainless steels that are nicely magnetic.

I was strongly-impressed by the hazard posed by various clothing items and jewelry when as a young child I met a friend of my father's.

This friend worked in a rare-metals refinery. One day an accident flung molten metal about the area. Some of it ran down inside this fellow's glove, and capillary action held it between his wedding ring and his finger.

He lost the finger.

Edna Mode in The Incredibles elaborates:

https://m.youtube.com/watch?v=1z_GF0KAAkg&pp=ygUYdGhlIGluY3JlZGlibGVzIG5vIGNhcGVz

A guy I know had the city-slicker habit of tucking his jeans into his cowboy boots. He managed to spill about three quarters of a cup (~240ml) of liquid nitrogen right into the top of his left boot. Being the typical macho city-slicker cowboy boot wearer, he neglected to tell us of his mistake for over half an hour. The eventual skin grafts ran from the inside of his shin, wrapping around the top of his foot and down to the middle third of his sole. The doctor commented that it was the first time he had dealt with second and third degree frostbite of the foot that didn't involve the toes ...

Not only dangerous, but I've spent a bunch of time around real cowboys and all of them wear their trousers over their boots.

No sex, no drugs, no wine, no women

No fun, no sin, no you, no wonder it's dark

Ex Apple Geniuses will recite with glee BOBSMEDS. The second B is "Bling"

I was 10 or 11, and messing about with old mains radios, usually getting them working too!

I wanted to swap one for another that was on a long extended cable that snaked round the skirting board to a wall socket - one of the old big three pin round types. with a festoon of adapters and several identical 2 pin plugs. I dutifully unplugged the cable, then not wanting bother to unwrap all the insulating tape on the cable joint chopped through it with wire cutters. There was a near deafening bang and the cutters were now welded shut and had two neat holes through the blade edges.

Dad came racing in from the lounge. I think he was more shocked than I was. Remember I mentioned the identical plugs... well they also had identical cloth covered cables, and I'd unplugged the wrong one. Oh, and that socket had been on a 30A rewirable fuse down in the cellar.

There was an electrical engineer in the year above me at Uni. He was super smart but a mechanical klutz. He was part of a joint electrical-mechanical engineering project developing an electric vehicle. During one session, he managed to drop a spanner directly across the battery terminals, shorting everything and melting the spanner! He really put the 'spark' into 'sparky'! Once in industry, the rumour was that he was chaperoned on-site by an electrician, to make sure he didn't electrocute himself or bring down the whole plant.

I switched on my laptop on my first day and it's been downhill ever since.