It's a 3-pole unit rated 40 A continuous at 40 °C, with an interrupting capacity of 220 kA at 240 V AC — that's the fault it can safely clear without welding contacts or rupturing the case. The shunt trip lets a remote signal (emergency stop, fire alarm, PLC output) force the breaker open; the aux switches report position back to the control system.
The interrupting ratings drop as voltage climbs: 220 kA at 240 V, 154 kA at 415 V, 121 kA at 440 V, and 17 kA at 500 V and 690 V. That 17 kA floor at 690 V is still respectable for most industrial secondary distribution — you'd only need a higher-rated upstream fuse if your available fault current exceeds that. The 40 A continuous rating holds steady from 40 °C to 50 °C, then derates to 37 A at 70 °C. Dimensions are 130 mm high, 76.2 mm wide, 70 mm deep — standard 3-pole MCCB footprint for a 40 A frame.