400 A MCCB with flat thermal curve and high interrupting capacity
The Siemens SENTRON 3VA2440-6HL32-0JC0 is a 3-pole molded case circuit breaker rated for line protection, carrying 400 A continuously across the full 40 °C to 70 °C ambient range without derating. Its interrupting capacity reaches 242 kA at 240 V and 187 kA at 415 V and 440 V, dropping to 121 kA at 500 V and 9 kA at 690 V. The maximum interrupting rating is 4 800 A, with a minimum of 600 A. This breaker includes a shunt trip release (STL) and two HQ auxiliary switches, and is built on the basic switch 3VA2440-6HL32-0AA0.
What the ratings mean for panel integration
The 400 A continuous rating holds flat from 40 °C to 70 °C, so no ambient derating curve is needed in warm enclosures or near other heat sources. The 242 kA SCCR at 240 V means this breaker can be placed at the service entrance or main distribution point where fault currents are highest, without cascading upstream. Dimensions of 110 mm depth, 138 mm width, and 248 mm height fit standard SENTRON panel cutouts; verify busbar alignment for the 3-pole footprint. Maximum power loss of 63.5 W should be factored into enclosure thermal calculations.