Rated 125 A continuous at 40 °C, it holds that current all the way up to 50 °C before it starts a gentle derating curve: 122 A at 55 °C, 120 A at 60 °C, 117 A at 65 °C, 114 A at 70 °C. That thermal profile matters if you're packing this into a high-ambient panel — the 125 A frame doesn't lose much until you push past 50 °C. The interrupting ratings are the headline: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V. The 121 kA at 415 V covers the common European three-phase distribution voltage, and the drop to 17 kA at 690 V is still respectable for a 125 A frame in a 690 V system.
Integration and panel fit
Three-pole, 76.2 mm wide (3 inches), 130 mm tall, 70 mm deep — that's a standard SENTRON 3VA footprint. The shunt trip (STL) release is built in, so you can remotely trip the breaker from an emergency-stop circuit or a PLC output without adding an external undervoltage module.