What this 100 A MCCB does on the line
The Siemens 3VA2010-5JQ32-0HH0 is a 3-pole SENTRON molded case circuit breaker rated 100 A continuous at 40 °C, with an ETU560 electronic trip unit that handles line protection. At 415 V and 440 V it still holds 121 kA, and at 690 V it drops to 3.4 kA, so the voltage class of your distribution determines which SCCR column you read.
The 100 A rating holds flat from 40 °C to 50 °C, then steps down: 96.25 A at 55 °C, 92.5 A at 60 °C, 88.75 A at 65 °C, and 85 A at 70 °C. Dimensions are 105 mm wide, 181 mm tall, 86 mm deep — standard SENTRON 3VA footprint for a 100 A frame, so it drops into the same DIN-rail or mounting-plate cutout as other 3VA100/200-series breakers.