MCCB for motor protection — 40 A, 3-pole, with undervoltage release
The interrupting capacity hits 187 kA at 240 V, 121 kA at 415/440 V, and still 75.6 kA at 500 V; at 690 V it holds 3.7 kA. That's a serious SCCR for a 40 A frame — suitable for high-fault industrial distribution.
That's unusual for an MCCB; most frames start dialing back above 40 °C. The motor protection design means the thermal-magnetic trip curve is shaped for motor inrush, not just feeder protection. At 415/440 V it still delivers 121 kA — enough for most industrial main feeders. The 3.7 kA at 690 V is a reminder that this is a 40 A frame; for 690 V applications with higher fault current, step up to a larger frame.
