400 A MCCB with flat temperature derating and shunt trip
The Siemens SENTRON 3VA2440-5MN32-0JA0 is a 3-pole molded case circuit breaker rated 400 A continuously from 40 °C through 70 °C — no derating curve to calculate across that band, which simplifies panel thermal budgeting for a motor protection circuit. Breaking capacity runs 187 kA at 240 V, 121 kA at 415/440 V, 75.6 kA at 500 V, and 9 kA at 690 V. That 187 kA at 240 V gives substantial fault-current headroom for low-voltage distribution; the 9 kA at 690 V is the ceiling for higher-voltage industrial feeds. Built-in phase failure detection and a shunt trip release (STL) as the auxiliary release make this a fit for motor branch circuits where loss-of-phase protection and remote trip capability are required. Maximum power loss is 63.5 W — relevant for enclosure heat-rise calculations when multiple breakers are ganged in a panel.
Physical integration
Dimensions are 248 mm high, 138 mm wide, 110 mm deep — a standard SENTRON 3VA frame footprint for panel mounting. Designed for motor protection duty, so the trip curve and magnetic pickup are calibrated for motor inrush rather than general distribution — verify coordination with downstream contactors and overload relays.