The Siemens 3VA1050-2ED42-0BC0 is a SENTRON molded case circuit breaker (MCCB) rated 50 A at 40 °C, with a 4-pole configuration and a breaking capacity of 52.5 kA at 240 V.
Breaking capacity and current ratings
Breaking capacity varies with system voltage: 52.5 kA at 240 V, 32 kA at 415 V, 13.6 kA at 440 V, and 7.5 kA at both 500 V and 690 V. The continuous current rating holds at 50 A from 40 °C up to 50 °C, then derates to 49 A at 55 °C, 48 A at 60 °C, 46 A at 65 °C, and 45 A at 70 °C. This thermal profile means the breaker can be applied in a warm enclosure without oversizing, as long as ambient stays under 50 °C.
The undervoltage release (UVR) is factory-installed, so no separate aux block is needed for that function.