What this MCCB brings to a hot, dusty panel
The Siemens 3VA1140-4EF32-0AD0 is a SENTRON molded case circuit breaker (MCCB) rated for 40 A continuous at 40 °C, with a thermal-magnetic TM240 release and 3 poles. It's built for line protection — the kind of duty where a breaker sits between a transformer secondary and a distribution bus, not cycling every shift but needing to clear a fault without hesitation when it happens. At 415 V it still holds 75.6 kA, and at 690 V it's rated 11.9 kA. The TM240 thermal-magnetic release means the thermal element tracks load heating for overload protection, and the magnetic instantaneous element handles short circuits.
Rated current holds at 40 A from 40 °C through 50 °C, then drops to 39 A at 55 °C, 38 A at 65 °C, and 37 A at 70 °C. In a cement plant control room that hits 55 °C in summer, you still get 39 A continuous — enough for a 40 A feeder if you're not pushing the thermal limit.