What this MCCB carries and where it fits
The Siemens SENTRON 3VA2440-6HN32-0CC0 is a 3-pole molded case circuit breaker rated for a continuous current Iu of 400 A, with an ETU350 electronic trip unit configured for line protection. It sits in the 3VA2 platform, which is the current-production SENTRON family — no lifecycle concern for a new BOM line. Breaking capacity is the headline: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 40 kA at 690 V. That covers most industrial service-entrance and feeder applications where high fault current is expected — think transformer secondaries or large motor control centers. Dimensions are 248 mm high, 138 mm wide, 110 mm deep — a standard 3-pole MCCB footprint that fits most switchboard and panelboard cutouts. The 110 mm depth means it clears shallow enclosures where a deeper frame would hit the gland plate.
Thermal derating and operating range
Rated continuous current holds at 400 A from 40 °C through 50 °C ambient. At 55 °C it derates to 384 A, at 60 °C to 376 A, at 65 °C to 368 A, and at 70 °C to 360 A. If the panel ambient runs above 50 °C — common in sealed enclosures or near ovens — the 400 A nominal needs that derate applied. Operating ambient range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The 66 W maximum power loss at full load is manageable but should be factored into enclosure thermal calculations, especially in a multi-breaker lineup.
Auxiliaries and releases built in
This unit ships with an undervoltage release (UVR) as the auxiliary release design, plus 2 auxiliary switches HQ. The UVR is factory-fitted — no field retrofit needed if the spec calls for undervoltage protection. The auxiliary switches provide status feedback for PLC or indication circuits. No voltage trigger, no communication function, no phase failure detection, and no ground fault monitoring on this variant. It is a straight line-protection breaker with the ETU350 — adjustable long-time, short-time, instantaneous, and ground-fault (though the ground-fault element is not wired on this version).
Sourcing and lifecycle posture
The integrated auxiliary trip is order code 3VA9608-0BB24, and the supplied basic switch is 3VA2440-6HN32-0AA0 — both are service spares if the breaker needs replacement internals without swapping the whole frame.