Its 400 A continuous current at 40 °C and 3-pole construction make it a fit for main or large feeder breakers in commercial and industrial switchboards. The TM220 overcurrent release is a thermal-magnetic design — the thermal element handles overloads with an inverse-time curve, and the magnetic element trips instantaneously on short-circuit. The interrupting ratings tell you where it can safely clear a fault: 121 kA at 240 VAC, 76 kA at 415 VAC, and 53 kA at 500 VAC. That 121 kA figure at 240 V means it can handle high available fault current common in North American 240/120 V distribution without needing a current-limiting fuse upstream. The 690 VAC rated operating voltage and 800 V rated insulation voltage confirm it is designed for 400 V and 480 V systems with margin.
Thermal derating and continuous current across temperature
This breaker holds its full 400 A rating from 40 °C through 50 °C. Above that, it derates: 392 A at 55 °C, 384 A at 60 °C, 376 A at 65 °C, and 367 A at 70 °C.
Dimensions are 248 mm high, 138 mm wide, and 110 mm deep. That 138 mm width is standard for a 3-pole MCCB in this class — it occupies three 45 mm pole spaces on a DIN rail or panel-mount base.