400 A MCCB with shunt trip — SENTRON 3VA2440-6HN32-0KA0
The Siemens SENTRON 3VA2440-6HN32-0KA0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous current across the full 40–70 °C ambient range — no derating needed up to 70 °C. It carries a shunt trip release (STL) for remote tripping, making it suitable for emergency-off or interlock circuits in motor control centers and distribution panels. Breaking capacity is 242 kA at 240 VAC, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 9 kA at 690 V — per the datasheet. That 242 kA at 240 V is the headline figure; at 415/440 V the 187 kA still covers most industrial fault levels. The 9 kA at 690 V is the limit for 690 V line-to-line applications; verify the available fault current at that voltage before specifying.
Dimensions and panel fit
Dimensions are 248 mm height, 138 mm width, 110 mm depth. The 138 mm width is the standard 3-pole MCCB footprint for this SENTRON frame size — it occupies three 45 mm pole spaces on a DIN rail or panel-mount base. Depth of 110 mm leaves clearance for rear-connected busbars or cable lugs in a typical distribution enclosure.
Key ratings and thermal performance
Rated 400 A continuous at 40 °C through 70 °C — no derating curve to apply across that band. Maximum power loss is 63.5 W. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The 400 A rating is the same at every 5 °C step from 40 to 70 °C, which simplifies panel thermal calculations.
Built-in shunt trip release
This variant includes a shunt trip (STL) auxiliary release — no undervoltage release, no ground-fault monitoring, no communication function. The shunt trip allows remote tripping via a control voltage, which is the standard method for emergency-stop circuits or supervisory shutdown in automated lines. No auxiliary switch is fitted; if status feedback is needed, a separate auxiliary switch module must be added.