What this MCCB carries on the line side
Rated 40 A at 40 °C with a symmetrical breaking capacity of 187 kA at 240 V AC, it clears high-fault scenarios without cascading upstream. At 415 V AC it still interrupts 121 kA, and at 690 V AC it holds 17 kA, so it's sized for industrial supply voltages where fault currents are substantial.
The 40 A rating holds flat from 40 °C up to 50 °C. Above that it derates gradually: 39 A at 55 °C and 60 °C, 38 A at 65 °C, and 37 A at 70 °C.
The breaker measures 130 mm high, 76.2 mm wide, and 70 mm deep — a 3-pole MCCB footprint that fits standard Siemens SENTRON mounting plates and busbar systems. The 76.2 mm width (3 inches) is a common pole spacing; you can land it in an existing panel that was laid out for a 3VA1-series frame without re-drilling. Power loss is 13.3 W maximum, which matters for thermal calculations in a sealed enclosure.