400 A SENTRON MCCB with ETU850 — what the ratings mean for your panel
The Siemens 3VA2340-6KP32-0HL0 is a 3-pole SENTRON molded case circuit breaker (MCCB) rated for line protection, carrying 400 A continuous at 40 °C through 50 °C before it begins to derate — 375 A at 55 °C, 350 A at 60 °C, 325 A at 65 °C, and 300 A at 70 °C. That means in a 40 °C panel you get full 400 A; if the enclosure runs hotter, the breaker self-limits without nuisance tripping. 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. Those are high-interrupting ratings — the breaker clears a fault without cascading upstream, which matters when you are coordinating a main or feeder in a high-fault installation. The electronic trip unit is an ETU850, which brings communication capability — this MCCB is not a dumb thermal-magnetic; it can report status and integrate into a monitored distribution system. Auxiliary contacts include 2 auxiliary switches plus 1 trip alarm and 1 electrical alarm switch (HQ version), and a shunt trip (STL) is built in for remote tripping. Rated insulation voltage is 800 V, so it is comfortable on 690 V systems with margin. Maximum power loss is 96 W — a figure to factor into enclosure thermal calculations if you are packing several breakers in a compact panel.
Physical fit and integration notes
Dimensions: 248 mm height, 138 mm width, 110 mm depth. That depth is the key clearance figure for enclosure depth — 110 mm means it fits standard 200 mm deep enclosures with room for wiring gutters behind the breaker. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The storage limits govern handling and warehousing, not running conditions. The basic switch (the interrupting module) is order code 3VA2340-6KP32-0AA0, and the integrated auxiliary trip is 3VA9688-0BL30 — these are the replaceable sub-assemblies if you ever need to service the breaker rather than swap the whole unit.