What this 3VA2340-6HN32-0KA0 brings to the panel
The interrupting ratings are serious: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 40 kA at 690 V. That kind of headroom means it handles high-fault utility feeds and large transformer secondaries without needing a current-limiting fuse upstream — it's a main or heavy feeder breaker, not a branch device. The ETU350 trip unit gives you adjustable long-time, short-time, and instantaneous protection curves, plus ground-fault capability if you add the right module (this variant ships without ground-fault monitoring). That's the standard electronic trip for this frame size — field-adjustable, so you can coordinate with downstream breakers on site.
Thermal derating — the number that matters in a real panel
The 400 A rating holds at 40 °C, 45 °C, and 50 °C — no derating needed in a typical 40 °C switchroom. At 55 °C it drops to 385 A, at 60 °C to 370 A, at 65 °C to 355 A, and at 70 °C to 340 A. If you're packing this into a non-ventilated enclosure or a hot corner of a MCC lineup, that's the curve to size against. Maximum power loss is 96 W — not trivial; that heat has to leave the enclosure. Factor it into your thermal budget if you're stacking multiple 400 A frames in one section.
Auxiliaries and accessories — what's on board
This unit ships with a shunt trip (STL) for remote tripping, plus a full auxiliary contact block: 2 auxiliary switches, 1 trip alarm switch, and 1 electrical alarm switch (the HQ configuration). That's enough for status feedback to a PLC and a separate alarm circuit without adding a second module. The basic switch assembly is order code 3VA2340-6HN32-0AA0, and the integrated auxiliary trip module is 3VA9688-0BL32 — useful to know if you're stocking spares or replacing a damaged subassembly in the field. No undervoltage release on this variant, and no communication module or phase-failure detection built in.
Physical fit and environment
Dimensions: 248 mm high, 138 mm wide, 110 mm deep. That's a standard 3-pole 3VA2 frame footprint — it mounts on a DIN rail or panel plate via the screw-on lugs. The 110 mm depth is shallow enough for most 400 mm deep enclosures, but check your gland-plate clearance if you're running cables behind the breaker. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Mechanical endurance is 15,000 operations — that's typical for a fixed-mounted MCCB in a distribution board, not a switching-duty contactor. Rated insulation voltage Ui is 800 V, so it's comfortable on 690 V systems with margin. The trip indicator and voltage trigger are both present, which helps during commissioning troubleshooting.