Motor protection MCCB with ETU350M trip unit
The Siemens SENTRON 3VA2140-5MN32-0KA0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A continuous current, purpose-built for motor protection duty. It carries a 187 kA interrupting capacity at 240 V, dropping to 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V — meaning it clears high fault currents across common industrial voltages without cascading upstream breakers. The ETU350M electronic trip unit provides adjustable overload and short-circuit protection curves, plus phase failure detection, making it appropriate for direct motor feeder protection in a distribution panel. Rated insulation voltage is 800 V, and the breaker includes an integrated shunt trip (STL) for remote tripping.
Panel integration and dimensions
Dimensions are 105 mm wide × 181 mm high × 86 mm deep — a standard MCCB footprint for DIN-rail or panel-mount installation. Maximum power loss is 75 W, which should be factored into enclosure thermal calculations, especially when multiple breakers are ganged.
Environmental and electrical ratings
Rated continuous current holds at 40 A from 40 °C through 50 °C ambient, then derates 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. Operating temperature range is -25 °C to 70 °C; storage from -40 °C to 80 °C. No auxiliary contacts or ground-fault monitoring are integrated on this variant.