SENTRON 3VA line protection MCCB — 40 A, high interrupting capacity
The Siemens 3VA1140-4EF32-0AB0 is a SENTRON molded case circuit breaker configured for line protection in distribution panels. It carries a rated continuous current Iu of 40 A with a flat thermal derating curve — still rated 40 A at 50 °C, dropping only to 36 A at 70 °C — so it holds its full rating in most ventilated enclosures without oversizing. Interrupting capacity is the headline: 121 kA at 240 V, 75.6 kA at 415 V, 52.5 kA at 440 V, and 11.9 kA at 690 V. That 121 kA figure at 240 V puts it well above typical 65 kA or 100 kA MCCBs — useful where fault current is high (large transformer, tight impedance path) and you need to avoid cascading failure upstream. Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — a compact 3-pole footprint that fits standard Siemens 3VA panel cutouts. Front protection is IP40, so it handles typical panel environments but not washdown.
Integration and mounting
Mounts in a standard SENTRON 3VA panel cutout — 76.2 mm width on a 3-pole footprint. The 70 mm depth leaves clearance for rear busbar connections and wiring troughs. Two auxiliary switches (HP type) are built in for remote status indication; no additional aux block needed for basic open/closed signalling. Storage range is -40 °C to 80 °C; operating range is -25 °C to 70 °C. The storage minimum matters if the breaker sits in an unheated warehouse before commissioning — it will tolerate cold soak without damage.