What you're bolting in
Siemens SENTRON 3VA1110-5EF32-0AM0 is a 3-pole molded case circuit breaker rated 100 A at 40 °C, carrying a TM240 thermal-magnetic release. That 100 A holds flat through 50 °C — only drops to 98 A at 55 °C and 91 A at 70 °C, so you don't lose headroom in a warm panel. Breaking capacity is the headline: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, 17 kA at 500 V and 690 V. That's serious fault-interrupting muscle for a 100 A frame — keeps selectivity downstream and avoids cascading upstream breakers. Base switch is 3VA11105EF320AA0 with 2 auxiliary HQ switches plus a short-circuit alarm switch built in.
Power loss maxes at 25 W — plan ventilation accordingly if you're packing several in a row.