What this MCCB carries
The Siemens 3VA2440-5HN32-0HL0 is a SENTRON molded case circuit breaker (MCCB) rated 400 A continuous at 40 °C through 70 °C — no derating needed across that span, which simplifies panel thermal management. It's a 3-pole line-protection design, meaning it's built for feeder and main breaker duty, not motor branch-circuit protection with integrated overloads. Breaking capacity is 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 9 kA at 690 V. That's a high-interrupting rating — suitable for installations with high available fault current, like large distribution panels or transformer secondaries. The breaker ships with a shunt trip (STL) auxiliary release and a complement of switches: two auxiliary switches, one trip alarm switch, and one electrical alarm switch. It also includes a voltage-trip indicator and a mechanical trip indicator. The basic switch inside is order code 3VA2440-5HN32-0AA0.
Panel fit and thermal budget
Mounts on a DIN rail or directly to a backplate. Dimensions are 138 mm wide, 248 mm tall, 110 mm deep — a standard 3-pole MCCB footprint that fits most Siemens SENTRON switchboard layouts. Maximum power loss is 63.5 W, so plan for that heat rejection inside the enclosure, especially if several breakers are ganged. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. That covers most indoor and sheltered outdoor installations without special enclosures.