The Siemens SENTRON 3VA2440-5MN32-0KH0 is a 3-pole molded case circuit breaker (MCCB) rated for motor protection duty, carrying a continuous current Iu of 400 A through the full 40–50 °C range before derating begins at 55 °C. Its interrupting capacity hits 187 kA at 240 V and 121 kA at 415 V, which means it can clear high-fault currents on large motor feeders without cascading upstream — a practical spec for panel builders sizing the main breaker on a 400 V distribution board feeding multiple drives.
Ratings & derating
The ETU350M electronic trip unit provides phase failure detection and a voltage trigger, with a shunt trip (STL) auxiliary release built in. Power loss maxes at 63.5 W, so ventilation in a sealed enclosure matters at full load. The breaker carries 2 auxiliary switches plus 1 trip alarm switch (HQ version) for status feedback to a PLC or annunciator panel. Derating curve: 400 A flat from 40 °C to 50 °C, then 384 A at 55 °C, 376 A at 60 °C, 368 A at 65 °C, and 360 A at 70 °C. Operating range is -25 °C to 70 °C; storage from -40 °C to 80 °C. For a 400 A continuous load in a 55 °C panel ambient, you lose 16 A — plan the cable and bus accordingly.
Dimensions & panel fit
Footprint: 138 mm wide × 248 mm high × 110 mm deep. The 138 mm width is a standard 3-pole MCCB form factor for Siemens SENTRON — drops into existing panel cutouts and busbar systems designed for the 3VA platform. Latching endurance rated at 15,000 operations, which covers frequent switching in motor control centers.