Breaking capacity and thermal derating
The Siemens SENTRON 3VA1140-5EF32-0JH0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous current at 40 °C, with a TM240 thermal-magnetic overcurrent release. Its breaking capacity is 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V — these are the fault currents it can safely interrupt at each voltage level, which determines the available fault current the upstream transformer or generator can deliver without exceeding the breaker's rating. The thermal derating curve holds at 40 A through 50 °C, then steps down to 38.4 A at 55 °C, 37.6 A at 60 °C, 36.8 A at 65 °C, and 36 A at 70 °C. If the panel ambient runs above 50 °C, the continuous load must be reduced accordingly; the 70 °C rating is the operating maximum, not a storage limit.
Panel fit and integration
The 3VA1140-5EF32-0JH0 measures 130 mm high, 76.2 mm wide, and 70 mm deep. The front face carries an IP40 protection rating — splash protection on the front only; the back and sides rely on the panel enclosure. It includes a shunt trip (STL) auxiliary release, a trip indicator, and a voltage trigger. The auxiliary contact configuration is 2 auxiliary switches plus 1 trip alarm switch (HQ). The integrated auxiliary trip order code is 3VA9688-0BL32 — order that separately if the shunt trip needs replacement. No undervoltage release, no communication function, no phase failure detection, and no ground fault monitoring are fitted on this variant.