Siemens SENTRON 3VA1140-4EF32-0KA0 — 40 A MCCB with Shunt Trip
The Siemens SENTRON 3VA1140-4EF32-0KA0 is a 3-pole molded case circuit breaker (MCCB) rated for 40 A at 40 °C, designed for line protection with a TM240 thermal-magnetic overcurrent release and an integrated shunt trip (STL) auxiliary release. Rated insulation voltage is 800 V, and breaking capacity reaches 121 kA at 240 V, 75.6 kA at 415 V, and 52.5 kA at 440 V — figures that define its fault-clearing capability across common distribution voltages. The shunt trip release allows remote tripping via a control signal, making this MCCB suitable for emergency-stop circuits or supervisory shutdown sequences in a panel.
Current Rating and Thermal Derating
Rated current holds at 40 A from 40 °C through 50 °C, then derates to 39 A at 55 °C and 60 °C, 38 A at 65 °C, and 37 A at 70 °C — a gentle slope that preserves most of the rating in warm enclosures. Maximum power loss is 10.8 W, which factors into thermal budgeting when grouping breakers on a DIN rail.
Physical Fit and Panel Integration
Dimensions are 130 mm height, 76.2 mm width, and 70 mm depth — a compact 3-pole footprint that fits standard Siemens SENTRON mounting bases and panel cutouts. No communication function, no undervoltage release, and no ground-fault monitoring on this variant — it is a straightforward line-protection MCCB with the shunt trip as the only auxiliary.