I get a disturbing amount of equipment that does not take into account the inrush current of starting many loads at the same time. While each individual device is protected by a breaker that can handle the inrush of it's load the main breaker for the equipment is not sized to handle every load starting at the same time. The fix is to include logic that starts things up one at a time but convincing engineers, project managers, and machine owners that they didn't think of everything is an uphill battle.
We used to have a turbopump that would trip the breakers every time you turned it on from cold. The pump seemingly attempted to spin up to max RPM before settling down to a more sustainable load. The only way to get the thing to stay on was to turn it on once, let it warm itself up on the initial attempt, trip the breakers, and try it another cycle now that it had some momentum and would pull slightly fewer amps. Sometimes took a few attempts to get that rolling start working.
That's a great way to lose the breaker though. If you're lucky the latch will fail. If you're unlucky it will weld shut.
loading story #50328595
Reminds me of computer fans, some bioses seem to do that ramp up for no reason thing as well.
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I assume you are talking beyond what (in the DIN rail world) type B/C/D breakers are meant to handle?
It's sort of a solved problem - the ones I'm aware of are things like LynTec sequenced panels built exactly for this, and Siemens' SENTRON semiconductor CBs where you can control then curve to your spec.
Convincing stakeholders though, is almost a job of its own.
These were all across-the-line, 3-phase 600v starters so there was no option to slowly start things up. Soft-starters would have been ideal but they are 5x the cost.
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