What this MCCB carries — and what it means for your panel
The Siemens SENTRON 3VA2440-6HL32-0KC0 is a 3-pole molded case circuit breaker rated for continuous 400 A across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling, which is unusual for a compact frame and simplifies panel thermal budgeting. The adjustable thermal-magnetic trip covers 600 A to 4 800 A, so one part number spans multiple feeder sizes; you set the pickup with the dial, not by swapping the trip unit. Short-circuit interrupting ratings climb to 242 kA at 240 V and hold at 187 kA through 440 V, then step down to 121 kA at 500 V and 9 kA at 690 V — the high 240–440 V numbers make this a strong candidate for transformer secondary or main switchboard protection where available fault current is high.
Panel fit and auxiliary complement
Footprint is 138 mm wide by 248 mm tall by 110 mm deep — fits a standard MCCB mounting pattern; the 138 mm width is three-pole wide, so verify bus-bar or cable-entry spacing in retrofit panels. Factory-fitted with a shunt trip (STL) and two auxiliary switches HQ — covers remote tripping and status feedback without adding a separate accessory module. The base switch variant is 3VA2440-6HL32-0AA0; the -0KC0 suffix adds the shunt trip and auxiliary switches at the factory rather than as field-installed kits.
Design and compliance context
Designated for line protection — not a motor-protective breaker with integrated overload class; use it for feeder, main, or distribution protection where the load is a transformer, busway, or cable run. No undervoltage release, no ground-fault monitoring, no communication function on this variant — those are separate order codes in the 3VA2 family. Operating temperature range -25 °C to 70 °C; storage range -40 °C to 80 °C. Maximum power loss 63.5 W at rated current — factor that into enclosure ventilation if the panel is densely populated.