What this 40 A MCCB delivers
The Siemens SENTRON 3VA1140-4EF36-0AA0 is a 3-pole molded case circuit breaker rated 40 A continuous at 40 °C, with a TM240 thermal-magnetic overcurrent release. It holds its full 40 A rating up to 50 °C, then derates to 39 A at 55 °C and 37 A at 70 °C — useful to know if the breaker sits near other heat sources in a crowded panel. Short-circuit breaking capacity is 121 kA at 240 V AC, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at both 500 V and 690 V. That 121 kA figure at 240 V tells you it handles high-fault utility feeds at lower voltages; the 75.6 kA at 415 V covers most European industrial distribution. Rated insulation voltage is 800 V. This is a line-protection design — no undervoltage release, no ground-fault monitoring, no communication module. It is a straight thermal-magnetic MCCB for branch or feeder protection where you need the interrupting capacity without auxiliary electronics.
Panel fit and mounting
Dimensions: 130 mm high, 76.2 mm wide (3 inches), 70 mm deep. That 76.2 mm width is a standard 3-inch footprint for a 3-pole MCCB — it drops into the same cutout as other SENTRON 3VA frames. IP40 on the front means it is protected against tools and wires larger than 1 mm, but the panel enclosure provides the overall IP rating. Maximum power loss is 10.8 W — negligible for thermal budgeting in a distribution board, but worth noting if you are packing multiple breakers into a small enclosure with limited ventilation.