The Siemens 3VA2325-6HK42-0AA0 is a 4-pole SENTRON molded case circuit breaker (MCCB) rated for 250 A continuous current at 40 °C, carrying the ETU340 electronic trip unit.
Current derating — the real-world continuous rating
Full 250 A is available up to 50 °C ambient. Above that the unit derates linearly: 242.5 A at 55 °C, 237.5 A at 60 °C, 230 A at 65 °C, and 220 A at 70 °C.
Trip unit and selectivity
The ETU340 is an electronic overcurrent release with adjustable N-conductor protection (OFF, 50%, or 100%). The thermal memory and long-time pickup settings (tr min and tr max both listed at 1500) are part of the coordination toolkit for achieving selective tripping downstream. For a mill electrical engineer building a selective coordination study, the ETU340 gives you the adjustability to hold in through motor-start inrush while clearing a bolted fault on a branch feeder. The 20 000 mechanical endurance cycles are adequate for a main or feeder breaker that sees infrequent operation — not a switching duty device.
Dimensions: 248 mm high, 184 mm wide, 110 mm deep. The 4-pole form factor (3 phases plus switched neutral) is standard for TN-S or TN-C-S systems where the neutral needs to be isolated and protected. Bolts into a fixed mounting plate or a withdrawable cradle depending on the SENTRON 3VA system frame.