Breaking capacity is specified per voltage: 75.6 kA at 240 V, 52.5 kA at 415 V, 32 kA at 440 V, and 11.9 kA at both 500 V and 690 V. That means at a 480 V panel feed (common in North American industrial), the available fault current must be below the 415 V rating — 52.5 kA — to stay within the breaker's interrupting capability. Rated insulation voltage is 800 V, so the breaker is suitable for 480/277 V and 600/347 V systems with margin.
Above that, derating applies: 78 A at 55 °C, 77 A at 60 °C, 75 A at 65 °C, and 74 A at 70 °C. If the panel ambient runs at 60 °C, the breaker's effective ampacity is 77 A — not 80.
Dimensions: 130 mm height, 101.6 mm width, 70 mm depth. The 4-pole width (101.6 mm) is the critical dimension for DIN-rail or mounting-plate spacing — verify the busbar stack and adjacent breaker clearances.