The Siemens 3VA1050-3ED42-0AC0 is a 4-pole IEC molded-case circuit breaker from the 3VA1 frame family, sized for 50 A continuous load with a fixed thermal-magnetic trip unit (TM210). Overload protection is fixed at Ir = 50 A (the TM210 thermal element), and short-circuit pickup is fixed at Ii = 10 × In (500 A magnetic). No field-adjustable dials on this variant — the protection curve is set at the factory, which simplifies BOM traceability but means the breaker is sized to the load, not tuned after installation. The unprotected neutral conductor (no integral neutral protection) is standard for 4-pole breakers where the neutral is solidly grounded and not switched. The nut keeper kit and two factory-fitted auxiliary switches (HQ type) come included, so the breaker arrives ready for panel integration without sourcing separate accessory kits. The auxiliary switches signal breaker status (open/closed/tripped) back to a PLC or status lamp — useful for remote monitoring on a distribution board.
The 4-pole footprint (three phases plus neutral) suits three-phase four-wire systems common in industrial and commercial power distribution — think sub-feed to a motor control center, lighting panel, or a machine disconnect. Coordination with upstream breakers or fuses should be checked per IEC 60947-2 selectivity rules, but the class N breaking capacity covers most standard industrial installations.