400 A MCCB with undervoltage release — SENTRON 3VA2 platform
The Siemens SENTRON 3VA2340-6HN32-0CA0 is a 3-pole molded case circuit breaker rated for 400 A continuous current at 40 °C, with a maximum interrupting capacity of 242 kA at 240 V AC. It is designed for line protection in industrial distribution panels, and includes an integrated undervoltage release (UVR) for coordinated shutdown on loss of control voltage. The 400 A frame size means it handles main feeder or large motor branch circuits in 400 V to 690 V systems. The interrupting ratings step down from 242 kA at 240 V to 187 kA at 415/440 V, 121 kA at 500 V, and 7.5 kA at 690 V — so the available fault current at your service voltage determines whether this breaker holds the SCCR without cascading upstream. Thermal derating starts above 50 °C: still 400 A at 50 °C, then 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. If your panel ambient runs hot, the continuous load must be reduced accordingly.
Dimensions and panel fit
The breaker measures 248 mm high, 138 mm wide, and 110 mm deep — a standard 3-pole MCCB footprint for the SENTRON 3VA2 family. Verify the mounting hole pattern and bus bar spacing against your existing panel layout; the 138 mm width typically matches a 3-pole base on 60 mm centers. Maximum power loss is 98.5 W at rated current — factor this into enclosure thermal calculations, especially in a sealed or high-density cabinet.