Siemens SENTRON 3VA1050-3ED42-0BA0 — 50 A, 4-Pole MCCB with TM210 Release and Undervoltage Trip
The Siemens SENTRON 3VA1050-3ED42-0BA0 is a 4-pole molded case circuit breaker (MCCB) rated for 50 A continuous current (Iu) across ambient temperatures up to 50 °C, with a linear derating curve that drops to 45 A at 70 °C — a detail worth noting if the breaker shares a warm cabinet with drives or transformers. Its breaking capacity steps with system voltage: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 7.5 kA at 690 V. That 52.5 kA at 415 V is the figure most panel builders will check against the utility transformer's prospective fault current on a 400 V distribution board. The overcurrent release is a TM210 thermal-magnetic type — fixed thermal and magnetic settings, no electronic adjustment. An undervoltage release (UVR) is built in, so the breaker trips on loss of control voltage; the auxiliary trip module is a separate order (3VA9608-0BB11). No auxiliary contacts ship with this variant.
Panel Fit and Mounting
The 3VA1050-3ED42-0BA0 measures 130 mm high, 101.6 mm wide, and 70 mm deep. The 101.6 mm width (4 inches) is standard for a 4-pole MCCB in the 3VA frame — it occupies four 25 mm module spaces on a DIN rail or bolts directly to a mounting plate. IP40 on the front face means it's protected against tools and wires >1 mm, but the enclosure must shield the sides and back in washdown zones.