What the ratings mean for fit
The Siemens 3VA2340-6KQ32-0KC0 is a 3-pole SENTRON molded case circuit breaker rated for 400 A continuous at 40 °C, with a 242 kA interrupting capacity at 240 V — that's the short-circuit current it can safely clear without welding contacts or rupturing the case, so it's sized for high-fault industrial mains panels, not branch circuits. The ETU860 is a microprocessor-based electronic trip unit with adjustable settings: the N-conductor protection is adjustable from OFF to 20% to 160% of the phase rating, and ground-fault monitoring works by summation current formation on the L-conductor, meaning it catches leakage to ground without a separate CT. Rated insulation voltage is 800 V. IP40 front protection keeps dust out of the trip mechanism in a panel. Power loss runs 96 W max at full load — that's heat that has to be managed in the enclosure, so factor it into your thermal budget if you're packing several breakers side by side.
Sourcing and lifecycle
It carries a communication function and comes with 2 auxiliary switches HQ as standard.
Panel fit and derating
Dimensions are 248 mm tall, 138 mm wide, 110 mm deep — that's a standard SENTRON 3VA2 frame footprint, so it drops into the same mounting cutout as other 3VA2 breakers in the 400 A class. Current rating holds at 400 A from 40 °C through 50 °C, then derates to 375 A at 55 °C, 350 A at 60 °C, 325 A at 65 °C, and 300 A at 70 °C — if your panel ambient runs above 50 °C, you need to size up or provide forced cooling. Breaking capacity drops with voltage: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 7.5 kA at 690 V — the 690 V figure is low enough that you should verify it against your available fault current if you're using this on a 690 V system.