That 630 A figure governs the main bus or feeder it protects — size the upstream transformer and downstream distribution for that load, not less. The breaking capacity climbs to 187 kA at 240 V AC and holds at 121 kA through 415–440 V, then tapers to 75.6 kA at 500 V and 17 kA at 690 V (–). For a 480 V panel, that 121 kA SCCR gives plenty of headroom against most utility fault levels without cascading upstream breakers. The ETU320 release is a basic electronic trip unit — no communication, no voltage trigger, no phase-failure detection (–). It handles line protection, meaning it clears overcurrent and short-circuit faults on the feeder. Four HQ auxiliary switches come integrated, and the integrated auxiliary trip is a 3VA9608-0BB24 — useful if you need a shunt trip or undervoltage release added later.
Above that, the continuous current derates stepwise: 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 (–).