The Siemens SENTRON 3VA2140-5MN32-0CL0 is a 3-pole molded case circuit breaker rated for 40 A continuous current across the full ambient range from 40 °C to 70 °C — no derating needed in a warm enclosure. Its interrupting capacity reaches 121 kA at 415 V, so it handles high-fault downstream of a large transformer or in a distribution panel without cascading upstream breakers. Designed specifically for motor protection, it includes phase failure detection and an undervoltage release, making it a fit for motor control centers where a loss of phase or a drop in control voltage should trip the load.
Interrupting ratings and mounting
At 240 V the breaker clears 187 kA; at 440 V it still holds 121 kA. At 500 V that drops to 75.6 kA, and at 690 V the rating falls to 3.7 kA — so for 690 V applications verify the available fault current stays well below that floor. The 86 mm depth, 105 mm width, and 181 mm height fit standard SENTRON panel cutouts; the footprint matches other 3VA frame sizes, so a panel laid out for a 3VA2116 accepts this 40 A unit without drilling new mounting holes.
The trip indicator is present, and the breaker includes a trip-alarm switch that changes state on a fault event — useful for remote annunciation in an MCC or a PLC-driven safety circuit. The basic switch supplied is order code 3VA21405MN320AA0, which confirms the internal mechanism is a factory-matched assembly, not a field-replaceable module.