What this MCCB delivers for your panel
The Siemens SENTRON 3VA2340-5HN32-0CH0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current at 40 °C, with a line protection design that prioritizes selectivity and fault isolation in distribution panels. Its 187 kA breaking capacity at 240 V means it can safely interrupt very high fault currents without upstream devices tripping — critical for main or tie-breaker positions where SCCR headroom is non-negotiable. At 415 V and 440 V the interrupting rating holds at 121 kA, dropping to 75.6 kA at 500 V and 7.5 kA at 690 V, so the voltage class of your system directly governs the available fault-clearing margin. The breaker carries an undervoltage release (UVR) as the auxiliary release, plus a configuration of 2 auxiliary switches and 1 trip alarm switch (HQ) — enough status feedback for a PLC-based monitoring scheme without an external interface module. Power loss is 98.5 W at rated load, which factors into enclosure thermal calculations if the breaker is in a sealed or high-density cabinet.
Thermal derating and physical fit
The 400 A rating holds from 40 °C through 50 °C ambient. Above that it derates linearly: 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 above 50 °C, the effective ampacity drops — size your load accordingly. The operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Physical dimensions are 248 mm high, 138 mm wide, and 110 mm deep. That 110 mm depth is the dimension that matters for enclosure depth clearance. The 138 mm width for a 3-pole frame is typical for this class, so it should drop into existing SENTRON or comparable MCCB mounting footprints without panel modifications.