400 A MCCB with 330 kA interrupting capacity
The Siemens SENTRON 3VA2340-7HN32-0BC0 is a 3-pole molded case circuit breaker rated for 400 A continuous current at 40 °C ambient, with a maximum breaking capacity of 330 kA at 240 V AC. That interrupting rating drops to 242 kA at 415 V and 440 V, 187 kA at 500 V, and 7.5 kA at 690 V — so the voltage class of your distribution system directly governs which fault level this breaker can clear. Designed for line protection, it carries an undervoltage release (UVR) and two auxiliary switches HQ for status feedback to a PLC or annunciator panel.
Thermal derating and panel fit
The 400 A rating holds through 50 °C; above that, derate to 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. If your enclosure runs hot — say a packed panel near a furnace line — size the upstream protection for the derated value, not the nameplate. The breaker measures 110 mm deep by 138 mm wide by 248 mm high, which fits standard SENTRON 3VA switchboard cutouts. Mounting and busbar kits are shared across the 3VA2 frame family, so a panel prepped for a 3VA2 frame accepts this unit without re-drilling.
Auxiliary and release configuration
The breaker ships with two auxiliary switches HQ (high-quantity contacts) and an undervoltage release (UVR) factory-installed. The UVR trips the breaker when control voltage drops below a set threshold — standard for emergency-stop chains or undervoltage protection schemes. No voltage-trigger or ground-fault monitoring is included; those are separate order-code variants in the 3VA2 family. Operating temperature range is -25 °C to +70 °C; storage range is -40 °C to +80 °C.