What this MCCB carries — and what it doesn't
The Siemens 3VA1110-4EF32-0JC0 is a SENTRON molded case circuit breaker rated for 100 A continuous at 40 °C, with a 121 kA interrupting capacity at 240 V. That 121 kA figure at 240 V is the headline — it tells you this breaker can safely clear a fault up to that level without welding contacts or venting plasma into the panel. At 415 V it still holds 75.6 kA, and at 690 V it's 11.9 kA, which tracks the physics of arc extinction in air. This is a line-protection design — no ground-fault module, no communication function, no undervoltage release fitted from the factory. It ships with a shunt trip (STL) and two HQ auxiliary switches. The 3-pole footprint (76.2 mm wide × 130 mm tall × 70 mm deep) fits standard SENTRON panel cutouts and busbar arrangements.
Thermal derating — the real continuous current
The 100 A rating holds flat from 40 °C through 50 °C. At 55 °C it drops to 98 A, at 60 °C to 96 A, at 65 °C to 94 A, and at 70 °C to 91 A. If your panel ambient runs hot — say a sealed enclosure next to a furnace line — that 91 A at 70 °C is the number to size against, not the catalog 100 A.
Panel fit and integration
The 70 mm depth and 76.2 mm width match the standard SENTRON 3VA1 family mounting footprint. It's designed for DIN-rail or screw-mount installation in distribution panels. The shunt trip (STL) and auxiliary switches are factory-fitted — no field-assembly required for those functions.