spitballing, i haven't designed a DC myself (yet)@star@mei edit: conclusions of this post are disputed
first you have a power consumption buffer on each of the power supplies. usually around 20%, to ensure long-term stability (in case efficiency factor degrades over time, plus to account for random short spikes)
it’s unlikely that all breakers trip at the same time (they’re actually designed not to!) so even if you managed to bring down your own rack / your own rack plus adjacent ones, you wouldn’t get a resonance cascade up to the main breaker because of the suddenly lowered load.
ALSO breakers are (i think?) specced not for a sum of server PSUs, but for a design value according to the wire gauge. and that is overspecced x1.5 if not more
altho, if you managed to install a killswitch in a lot of power supplies that launched a servo which could, hypothetically speaking, bridge live to neutral… and then you activated a bunch of them at once… maybe you’d knock out one of the phases :D
