Siemens 3VA2340-6HN32-0AJ0 SENTRON MCCB, 400 A, 3-Pole, 242

The Siemens SENTRON 3VA2340-6HN32-0AJ0 is a 3-pole molded case circuit breaker rated for 400 A continuous current at 40 °C, with a breaking capacity of 242 kA at 240 V AC — enough to handle high-fault utility feeds or large transformer secondaries without cascading upstream. At 415 V and 440 V the interrupting rating holds at 187 kA; at 500 V it drops to 121 kA, and at 690 V to 7.5 kA — so for a 480 V distribution panel this breaker clears faults well above typical available fault currents, but on a 690 V drive line you need to verify the available fault current stays under 7.5 kA. Thermal derating is modest: the 400 A rating holds through 50 °C ambient, then steps down to 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C — useful to know if this breaker sits in a non-ventilated enclosure near heat sources.

Auxiliary switching and monitoring