At 40 °C, 45 °C, and 50 °C the breaker holds a full 100 A; it only starts to derate above 55 °C, dropping to 91 A at 70 °C. That means in a warm panel — say 50 °C ambient — you still get the full 100 A without oversizing. The 75.6 kA at 415 V is the figure to check against your utility transformer or generator fault current; at 240 V it jumps to 121 kA, so it handles most North American secondary-side faults easily.
The 3VA1110-4EF32-0BC0 measures 76.2 mm wide, 130 mm tall, and 70 mm deep — a standard 3-pole MCCB footprint that drops into most SENTRON or third-party distribution panels without re-drilling. The undervoltage release is wired in; the two HQ auxiliary switches give you one N/O and one N/C contact for PLC or status lamp feedback.