What it is and what it does
The Siemens SENTRON 3VM1140-3ED32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection — the primary feeder breaker in a distribution panel or a branch circuit protector for motor control centers. Rated 40 A continuous at 40 °C through 50 °C, it holds that full rating across typical panel ambient conditions; at 70 °C it still carries 37 A, so derating is minimal unless the enclosure runs hot. Breaking capacity hits 76 kA at 240 VAC, 53 kA at 415 VAC, 32 kA at 440 VAC, and 12 kA at 500 VAC — that 76 kA figure at 240 V means it handles high-fault utility feeds in North American panels, while the 53 kA at 415 V covers most European industrial distribution. The TM210 thermal-magnetic release provides fixed thermal and magnetic trip curves — no interchangeable trip units, so the breaker is sized for a specific load and stays that way.
Panel fit and mounting
At 76.2 mm wide, 130 mm tall, and 70 mm deep, this MCCB fits standard Siemens SENTRON mounting bases and busbar systems — the 70 mm depth is shallow enough for compact enclosures, but verify the busbar connection clearance for the TM210 terminals. Front IP40 protection means it's fine for dry indoor panels; no washdown rating, so keep it out of wet or dusty environments unless it's behind a sealed enclosure door. Power loss is 11 W max at rated load — negligible for a single breaker, but if you're packing a dozen of these in a small panel, that heat adds up and may drive ventilation requirements.