Siemens 3VA1140-5EF36-0KC0 MCCB, 40 A, 187 kA at 240 V

Line protection with high interrupting capacity

Its interrupting capacity is the headline: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V — these are the fault currents it can safely clear without rupturing.

Thermal derating and endurance

The 40 A rating holds flat from 40 °C to 50 °C, then derates linearly: 38.4 A at 55 °C, 37.6 A at 60 °C, 36.8 A at 65 °C, and 36 A at 70 °C.

Built-in shunt trip, no undervoltage release

There is no undervoltage release, so the breaker will not automatically open on a control-voltage dip. No communication function, phase failure detection, or ground fault monitoring are built in; this is a straightforward line-protection MCCB with a remote-trip option.