shop talk from my electrical engineering days:
I think my favorite power-related mishap involved the board layout engineer using the wrong DC barrel plug in the layout (center-negative instead of center-positive)
none of us caught it during layout review because we were focusing on the complicated things like the FPGA and the main component
the board is normally powered by USB so everything was testing fine on the first prototypes
until like Friday afternoon when we were like "okay let's make sure the DC power failover works" and we go to plug it in and the fuckin power-source-selection IC pops and leaves a crater
that was fun
My second internship we had a power supply known as the Trace Breaker. It was a 15V, 50A linear supply that weighed a fucking ton. You'd use it on boards with a short somewhere and ramp the voltage slowly while using a thermal camera. I actually had a board I designed fail and we couldn't break a trace even at max amps, because the PCB shop failed to etch a corner of the board under some connectors! It was a huge power/ground short that was like 20% of a layer. XD
@zetasyanthis @rey for stuff like that, i think an H-field probe is a lot easier to use
if a lot less impressive
remind us to tell you about liquid crystal hotspotting sometime
-F
@zetasyanthis @rey We once put a piece of #30 gauge wire wrap wire across the terminals of an "ultra high current" (capable of up to 1500 A) SMU and programmed it to just do pulses of current increasing until it breaks
it made it to several amps before it just melted
-F
@zetasyanthis @rey this actually had a purpose, believe it or not: we wanted to determine a rough measurement of the fusing current of a similar type of wire
figured this was a good enough approximation so put it in there and let it do its thing
it actually fried the socket we poked it into in the process, which indicates there was a lot of contact resistance
-F
@zetasyanthis @rey you should hear the clunking of the contactor when we turn it on
it can only do very short pulses of 1500 A, of course
It came with banana plug cables with a little mechanism inside the plugs that makes them expand when you twist a collet, to increase contact pressure. they're also on some #6 AWG welding cable instead of the more conventional for banana plugs #14 AWG
-F
@zetasyanthis @rey they're designed for it! these are specifically designed to be used for high current
-F