Motor protection MCCB with ETU350M LSI trip
The Siemens 3VA2440-7MN32-0AL0 is a 3-pole IEC frame 630 molded case circuit breaker rated 400 A continuous, built around the ETU350M electronic trip unit with LSI protection — long-time (Ir), short-time (Isd), and instantaneous (Ii). Overload protection Ir is adjustable from 160 A to 400 A; short-circuit protection Isd adjusts 3 to 15 × Ir, and the instantaneous pickup Ii is fixed at 15 × In. The 110 kA breaking capacity at 415 V (class C) means it clears high-fault currents on a 400 V motor branch without upstream coordination issues — sized for large pump, compressor, or conveyor drives fed from a transformer-rated switchboard.
Built-in auxiliary and alarm switching
Factory-fitted with 2 changeover auxiliary switches (H configuration) and 1 changeover trip alarm switch. That covers remote status indication for the closed/tripped state and a separate alarm contact that closes only on a fault trip — useful for feeding a PLC digital input or a panel beacon without adding external interposing relays. The nut keeper kit on the terminals simplifies panel wiring: the captive nut stays aligned during torque-down, a small time-saver on a multi-breaker lineup.