What it is and what it does
The Siemens 3VA1040-3ED32-0JC0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in distribution panels. It carries a continuous current rating of 40 A at 40 °C, derating to 36 A at 70 °C, and breaks fault currents up to 75.6 kA at 240 V — enough to handle high-fault utility feeds or transformer secondaries without cascading upstream. Three poles, rated insulation voltage 800 V, and a 3-pole footprint that fits standard SENTRON panel mounting. The unit ships with a shunt trip (STL) release and two HQ auxiliary switches built in — no separate add-on modules needed for remote trip or status feedback.
Breaking capacity — what the numbers mean for your fault study
The 75.6 kA at 240 V is the highest interrupting rating on this breaker; at 415 V it drops to 52.5 kA, at 440 V to 32 kA, and at 500 V / 690 V to 7.5 kA. That steep derating above 480 V means this frame is really at home on 240 V or 400 V-class systems where fault currents are high — not on 690 V motor circuits where available fault is modest. Compared to the 3VA1010-3ED36-0AA0 (a 100 A frame in the same SENTRON family), the 3VA1040-3ED32-0JC0 shares the same 3-pole form factor and shunt trip option but is sized for a 40 A load rather than 100 A. The panel cutout and bus connection pattern are identical — swap the breaker, not the panel layout.
Panel integration — dimensions and mounting
Dimensions: 130 mm high, 76.2 mm wide, 70 mm deep. The 76.2 mm width (3 inches) is the standard SENTRON 3-pole MCCB footprint — fits existing bus-bar and DIN-rail layouts without re-drilling. Depth of 70 mm leaves clearance for rear-connection terminals and wiring troughs in a 200 mm deep enclosure.