The Siemens 3VA2040-7KQ32-0AA0 is a SENTRON molded case circuit breaker (MCCB) rated for 40 A continuous current at 40 °C ambient, with a 3-pole configuration designed for line protection. Its interrupting capacity reaches 330 kA at 240 V, dropping to 242 kA at 415 V and 440 V, and 187 kA at 500 V — at 690 V it still holds 3 kA. That SCCR headroom means this breaker can stand up to a high-fault utility feed without cascading failure upstream, critical for maintaining selectivity in a distribution panel. Rated insulation voltage is 800 V, and the breaker carries a communication function plus summation-current ground-fault monitoring — it can report its state and leakage condition to a BMS or PLC without an add-on module. That makes it a fit for a monitored distribution board where you want to know when a branch trips or a ground fault develops, not just after the lights go out.
Integration and Mounting
The breaker measures 105 mm wide, 181 mm high, and 86 mm deep — a standard MCCB footprint that fits most DIN-rail or panel-mount enclosures without a custom gland plate. Verify the mounting cutout and bus-bar spacing against your existing panel layout before committing the BOM line. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The 40 A rating holds flat across the entire 40 °C to 70 °C ambient span — no derating curve to calculate for a warm panel environment. Maximum power loss is 1.2 W, negligible for thermal budgeting.