The Siemens 3VA1040-4ED32-0DA0 is a SENTRON 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous at ambient temperatures from 40 °C to 50 °C, with a slight derating curve above that — 38.4 A at 55 °C, down to 36 A at 70 °C. Its interrupting capacity hits 121 kA at 240 V AC, 75.6 kA at 415 V, 52.5 kA at 440 V, and holds 11.9 kA all the way to 690 V.
Integration & Ratings That Matter
The 3-pole footprint is 76.2 mm wide, 130 mm tall, 70 mm deep — standard for a SENTRON 3VA frame, meaning it drops into existing 3VA panel layouts without re-drilling the mounting plate. Power loss maxes out at 13.3 W, which is modest for a 40 A MCCB; ventilation in a sealed enclosure is still advisable if you're stacking several in a row.
If you're looking at the 3VA1110-5EF32-0LA0 as a potential second-source, the key difference is the frame size. The 3VA1040-4ED32-0DA0 is a 40 A frame; the 3VA1110 series starts at 100 A and goes up. Both are 3-pole SENTRON MCCBs with UVR options, but the 3VA1110 is physically larger (wider and taller) and carries higher interrupting ratings at the same voltage points. They are not footprint-interchangeable — you cannot drop the 3VA1110 into a panel cutout designed for the 3VA1040 without reworking the bus bars and mounting holes. For a 40 A line-up, stick with the 3VA1040 frame.