The Siemens SENTRON 3VA2440-6HL32-0AE0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection at a continuous current Iu of 400 A. It carries an ETU320 electronic trip unit — a basic adjustable thermal-magnetic release — and is built for high-fault applications: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and still 40 kA at 690 V. That means it can be placed at the main distribution point where fault currents are highest, without needing a current-limiting upstream device.
Current derating and thermal management
The breaker holds full 400 A up to 50 °C ambient. Above that it derates linearly: 384 A at 55 °C, 376 A at 60 °C, 368 A at 65 °C, and 360 A at 70 °C. If your panel internal temperature runs above 50 °C — common in sealed enclosures with other heat sources — you need to account for that 10 % drop at 70 °C. The maximum power loss is 63.5 W, so ventilation or a larger enclosure may be required to stay within the operating range of -25 °C to 70 °C.
Auxiliary contacts and integration
This variant ships with 4 auxiliary switches (HQ type) — enough for remote status indication, interlocking, or PLC feedback without adding a separate module. The auxiliary release slot is empty (no shunt or undervoltage release fitted), and there is no ground-fault monitoring module. If you need those, the basic switch platform is 3VA2440-6HL32-0AA0, and the integrated auxiliary trip is 3VA9608-0BB24. The breaker is 138 mm wide, 248 mm high, and 110 mm deep — standard SENTRON 3VA 400 A frame footprint, so it drops into existing panel cutouts and busbar arrangements for the series.