400 A MCCB with 440 kA SCCR — what the ratings mean for your panel
The Siemens SENTRON 3VA2440-8KQ42-0AA0 is a 4-pole molded case circuit breaker rated for 400 A continuous current across the full 40 °C to 70 °C ambient range — no derating needed up to that ceiling. Its interrupting capacity hits 440 kA at 240 VAC, 330 kA at 415/440 V, and still delivers 220 kA at 500 V, 52.5 kA at 690 V. That SCCR headroom means it can sit at the main or feeder position in high-fault panels without cascading coordination issues upstream. The breaker is designed for line protection and includes communication capability plus ground-fault monitoring via summation current formation on L+N.
Integration — panel fit and wiring notes
Dimensions are 248 mm high, 184 mm wide, 110 mm deep (–). The 4-pole footprint matches standard SENTRON 3VA panel cutouts; verify busbar and lug spacing against your existing switchboard layout. Power loss is 63.5 W maximum — account for thermal rise in a sealed enclosure. Operating temperature range is -25 °C to 70 °C (–); storage from -40 °C to 80 °C (–).