The Siemens SENTRON 3VA2440-5HK42-0AA0 is a 4-pole molded case circuit breaker rated for continuous 400 A at 40 °C ambient, with the ETU340 electronic trip unit governing the protection curve. That 400 A holds flat through 50 °C; at 55 °C it derates to 384 A, and at 70 °C to 340 A — so if your enclosure runs hot, the real continuous capacity drops. The interrupting ratings are the headline here: 187 kA at 240 V, 121 kA at 415 V and 440 V, 76 kA at 500 V, and 10.2 kA at 690 V. The ETU340 trip unit gives adjustable long-time pickup (Ir) from 1500 A to 4000 A and short-time (Ii) fixed at 6000 A, with N-conductor protection configurable OFF, 50%, or 100% of phase setting.
The breaker measures 184 mm wide, 248 mm high, and 110 mm deep — a 4-pole frame that needs a solid 184 mm of DIN-rail or mounting-plate width. The optional motor drive (listed as a product extension) allows remote racking, useful for automated disconnection in larger lineups.
With the ETU340's adjustable long-time and fixed short-time pickup, you can coordinate this breaker downstream of a larger SENTRON or upstream of smaller branch MCCBs. The 187 kA at 240 V gives plenty of headroom for most industrial service entrances; the 10.2 kA at 690 V is more modest, so check your available fault current if you're on a 690 V system.