What this MCCB carries and where it fits
The Siemens 3VA1040-3ED32-0DH0 is a SENTRON molded case circuit breaker (MCCB) rated 40 A at 40 °C, maintaining that full rating through 50 °C before derating to 36 A at 70 °C. Its interrupting capacity hits 75.6 kA at 240 V, 52.5 kA at 415 V, and 32 kA at 440 V, with a floor of 7.5 kA at 500 V and 690 V. That spread covers most industrial low-voltage distribution panels where high fault current is expected — think main feeders or large subfeeders in a plant with a 1000 kVA transformer close by. The 800 V rated insulation voltage confirms it is built for 480/600 V class systems with headroom. Three poles, line-protection design, and a built-in undervoltage release mean this breaker trips on loss of control voltage — a standard requirement for emergency-stop circuits and safety-related disconnects in conveyor or machine-tool panels. The auxiliary switch complement (2 aux + 1 trip alarm HQ) gives remote status feedback without an add-on module.
Panel fit and thermal derating
Dimensions are 130 mm high, 76.2 mm wide, 70 mm deep — a standard 3-pole MCCB footprint for DIN-rail or panel-mount installation. The 13.3 W maximum power loss is modest for a 40 A frame; adjacent devices in a sealed enclosure need no special derating at that dissipation. Operating range spans -25 °C to 70 °C, so it handles unheated electrical rooms and outdoor-rated enclosures alike.
