Siemens SENTRON 3VA2225-5KP32-0BH0 — 250 A MCCB with ETU850 Trip Unit
It is fitted with the ETU850 electronic overcurrent release, which provides adjustable protection curves for feeder and main breaker applications. The interrupting capacity reaches 187 kA at 240 V, 121 kA at 415 V and 440 V, 79 kA at 500 V, and 5.1 kA at 690 V — figures that govern selectivity and SCCR headroom in the distribution panel.
Thermal Derating and Ambient Constraints
The 250 A rating holds up to 50 °C ambient. Above that, the continuous current must be derated: 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. Maximum power loss is 50.5 W, which factors into enclosure thermal management for a panel builder.
Auxiliary and Communication Capabilities
The integrated auxiliary trip module is order code 3VA9608-0BB11; the basic switch is 3VA2225-5KP32-0AA0. A trip indicator is present for visual fault confirmation.
Verify the gland-plate cutout and phase-spacing against the existing panel layout before wiring.