The 30 kA breaking capacity per IEC 60947-2 tells you this MCB can safely interrupt fault currents up to that level without welding its contacts or cascading failure upstream; under UL 1077 / CSA C22.2 No. 235 the interrupting rating is 5 kA, which governs North American supplementary-protection installations. The 400 V AC rating covers most 3-phase line-to-line panel voltages in Europe and Asia; single-phase and multi-phase operation both carry a 440 V maximum, so it handles 480Y/277 V systems as well. The thermal environment: rated for -40 °C to +75 °C ambient, with derating guidance above 40 °C — the influence table caps relative humidity at 95% up to 55°C, then 55% up to 70°C, then 35% up to 75°C. That's relevant if the panel sits near a furnace, oven, or outdoor enclosure in direct sun.
Integration — DIN-rail fit and panel notes
Three modular width units at 54 mm wide — matches standard Siemens 5SY series busbar and comb spacing. The sealable option lets a panel builder apply a tamper-evident seal after commissioning — required on some utility-metered or safety-audited feeders. Touch protection is integral, so no separate finger-safe covers are needed for the live terminals at IP20 with connected conductors.