MCCB for main feeder or large motor protection
The Siemens SENTRON 3VA2440-7HN32-0AA0 is a molded case circuit breaker rated for 400 A continuous current — no derating needed from 40 °C up through 70 °C, so it holds its full rating even in a warm enclosure. The ETU350 electronic trip unit gives you adjustable long-time, short-time, instantaneous, and ground-fault protection curves, which makes this breaker suitable for main feeders or large motor circuits where you need coordination selectivity downstream. Breaking capacity sits at 330 kA at 240 V AC, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 9 kA at 690 V. Those numbers cover most industrial service-entrance and distribution panels where fault current runs high — the 240 V rating in particular handles utility transformer secondaries without needing a current-limiting fuse upstream.
Panel fit and wiring
The 3VA2440-7HN32-0AA0 measures 248 mm tall, 138 mm wide, and 110 mm deep. That 138 mm width is the standard 3-pole MCCB footprint for this frame size — it bolts into the same mounting pattern as other SENTRON 3VA breakers in the 400 A class, so swapping one in doesn't mean redrilling the backplate or reworking bus bars. Maximum power dissipation is 63.5 W at rated load — something to account for in thermal calculations if the panel is densely packed. The breaker is designed for line protection (no undervoltage release, no communication module, no ground-fault monitoring), so it's a straightforward thermal-magnetic-plus-electronic replacement for existing feeder breakers.