SENTRON 3VA1 MCCB — 40 A, 3-Pole, High Interrupting Capacity
The Siemens 3VA1140-6EF32-0HC0 is a SENTRON molded case circuit breaker (MCCB) rated for 40 A continuous current at 40 °C ambient, across a 3-pole configuration. It carries a 220 kA breaking capacity at 240 V AC, stepping down to 154 kA at 415 V, 121 kA at 440 V, and 17 kA at both 500 V and 690 V — meaning it can clear high-fault currents upstream of a distribution panel without cascading to the main breaker, provided the SCCR coordination study supports it. Rated insulation voltage is 800 V, and the breaker includes a shunt trip (STL) auxiliary release and two HQ auxiliary switches. The supplied basic switch carries order code 3VA11406EF320AA0. No undervoltage release or ground-fault monitoring version is fitted on this variant.
Thermal Derating and Ambient Constraints
Rated current holds at 40 A from 40 °C through 50 °C ambient, then derates to 39 A at 55 °C and 60 °C, 38 A at 65 °C, and 37 A at 70 °C. Operating ambient range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. Maximum power loss is 10.8 W. If the breaker sits in a sealed enclosure with other heat sources, the 70 °C ceiling and the derating curve govern the real-world ampacity — not the 40 A nameplate.
Dimensions and Panel Fit
Width 76.2 mm (3 in), height 130 mm (5.12 in), depth 70 mm (2.76 in). Three-pole footprint matches the standard SENTRON 3VA1 cutout; verify the existing DIN-rail or screw-mount backplate accommodates the 70 mm depth behind the panel door — shallower enclosures may need a spacer.