Someone had a short fuse? Got an open one to replace ...
Impressive. My personal record is 315A, but that was three of them. And, we also triggered the 1250A circuit breaker that sat upstream. The EE surveying the problem (which turned out to be a busbar short on the load side of an UPS that the UPS compensated for by going into internal bypass and frying its solid state relays and the upstream fuses) muttered something about "improper selectivity" and reprogrammed the circuit breaker to be a tad slower to trig.
A problem that plagues three-phase systems, especially temporary ones, is the tendency to connect the big load on phase one, a boom box on phase two, and some festoon lights on phase three. Repeat for 10 consumers and you have one glowing and two idling phases. This had me swapping the phase one 150A fuse in a outside distro cabinet in a forest, in the middle of the night, in pitch black darkness. Except for the photons from one small Maglite.