630 A MCCB with 187 kA interrupting capacity — what that means for your main feeder
The Siemens 3VA2463-5HN32-0HK0 is a 3-pole SENTRON molded case circuit breaker rated 630 A at 40 °C ambient, with the ETU350 electronic trip unit. The real headline is the interrupting capacity: 187 kA at 240 V AC, tapering to 121 kA at 415/440 V, 75.6 kA at 500 V, and 9 kA at 690 V.
ETU350 electronic trip — selectivity and coordination flexibility
That matters for coordination: you can set the short-time delay to ride through downstream faults, keeping this breaker closed while a branch breaker clears a bolted fault. The trip indicator and electrical alarm switch provide status for a PLC or annunciator panel. The shunt trip release allows remote tripping via an emergency-stop circuit or undervoltage relay — wired separately from the main load path.
Current derating across ambient temperature
At elevated panel temperatures the breaker derates: 612 A at 45 °C, 593 A at 50 °C, 575 A at 55 °C, 557 A at 60 °C, 538 A at 65 °C, and 520 A at 70 °C. If your switchgear enclosure runs hot — common in compact MCCs or outdoor cabinets in direct sun — use the 50 °C or 60 °C figure for your continuous load calculation.
Panel integration and auxiliary wiring
The auxiliary switch complement includes one auxiliary switch, one trip alarm switch, and one electrical alarm switch — all factory-fitted, wired to the terminal block on the front face. The shunt trip release (STL) is wired separately; verify polarity on DC control circuits to avoid coil damage.