What it is and what it does
The Siemens SENTRON 3VM1140-5GE42-0AA0 is a 4-pole molded case circuit breaker (MCCB) rated for 40 A continuous current, with a TM220 thermal-magnetic overcurrent release. It's line protection — the primary disconnect and fault interrupter in a distribution panel or motor control center feeder. The breaking capacity climbs to 187 kA at 240 V AC, drops to 121 kA at 415 V, 76 kA at 440 V, and 17 kA at 500 V. That 187 kA figure at 240 V tells you this breaker is built for high-fault locations — think transformer secondaries or large bus risers where available fault current is serious. The 17 kA at 500 V still covers most industrial distribution needs.
Ratings that matter for fit
Rated insulation voltage Ui is 690 V, max operational voltage with DC is 500 V. The 40 A rating holds steady from 40 °C up to 50 °C, then derates to 39 A at 55–60 °C, 38 A at 65 °C, and 37 A at 70 °C. If your panel runs hot — say a sealed enclosure in a foundry — you lose 3 A off the top. Plan the load accordingly. Dimensions: 130 mm high, 101.6 mm wide, 70 mm deep. That 70 mm depth is shallow enough to fit a standard 200 mm deep enclosure without crowding the gland plate. IP40 on the front — fine for a dry indoor panel, not for washdown. The TM220 release means the thermal element is fixed at 40 A (Ir max. 40 A) and the magnetic pickup is fixed at 220 A. No field-adjustable dials — what you order is what you get. N-conductor protection is rated at 100%.
Lifecycle and sourcing reality
That said, if you're doing a new panel design, the 3VA series (e.g., 3VA1110-5EE32-0JA0) is the current-generation sibling with a wider accessory ecosystem and electronic trip options. The 3VM1 is still a valid BOM line for existing designs or where a thermal-magnetic fixed-release is exactly what the spec calls for.
What's in the box — and what's not
No communication function, no ground-fault monitoring, no motor drive option. This is a bare breaker — line protection only. Power loss is 10.8 W maximum at rated current. Mechanical endurance is 12,000 operations. Storage range: -40 °C to 80 °C; operating range: -25 °C to 70 °C.