Motor protection breaker, 500 A frame, 55 kA @ 415 V
The Siemens 3VA2450-5MN32-0KJ0 is a 3-pole IEC frame 630 motor protection circuit breaker with a breaking capacity class M rated at 55 kA at 415 V. It carries an In of 500 A and uses the ETU350M electronic trip unit with LSI protection — long-time (Ir adjustable 200 A to 500 A), short-time (Isd adjustable 3 to 15 × Ir), and instantaneous (Ii fixed at 15 × In). That LSI curve is sized for motor starting inrush and coordinated downstream with contactors and overload relays per IEC 60947-4-1.
Integrated accessories for panel wiring
Factory-fitted with a shunt trip (STL) rated 220-250 V DC or 208-277 V AC, plus two auxiliary switches (HP) and one trip alarm switch (HP). The nut keeper kit is included — a detail that saves time during DIN-rail or mounting-plate installation on a panel backplane. All auxiliary contacts are wired to the same terminal block, so the panel builder can land the remote trip and status signals without opening the breaker cover.