The adjustable instantaneous trip Ii is fixed at 1250 A.
The 121 kA figure at 240 V is high for a 1-pole 125 A frame — it gives solid SCCR headroom on 240 V line-to-neutral circuits, allowing selective coordination with downstream branch breakers without cascading.
Rated 125 A from 40 °C through 50 °C, then derates to 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, and 114 A at 70 °C. The 25.4 mm width (1 inch) per pole matches the standard SENTRON 3VA footprint — fits existing DIN-rail or panel-mount layouts without re-spacing.
