What this MCCB delivers
The Siemens 3VA2140-6KP42-0AA0 is a SENTRON molded case circuit breaker rated for 40 A continuous current (Iu) across the full ambient range from 40 °C to 70 °C — no derating needed up to that ceiling. Four poles, line protection version, with the ETU850 electronic trip unit. Breaking capacity hits 242 kA at 240 V AC, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 3.8 kA at 690 V. That 242 kA figure at 240 V means it handles the highest available fault currents on a 240 V secondary without upstream coordination worries — it's sized for the worst-case short-circuit at the main distribution board. Rated insulation voltage is 800 V, so it's comfortable on 690 V systems with margin. Communication function is built in — the ETU850 supports data exchange for power monitoring and trip-event logging. Power loss maxes at 1.6 W, negligible for panel thermal budgeting. Latching endurance is rated at 20,000 operations, which covers frequent switching in process lines or backup generator circuits.
Panel fit and environment
Dimensions are 181 mm high, 140 mm wide, 86 mm deep. The 140 mm width is a standard 4-pole MCCB footprint — it drops into the same mounting cutout as other SENTRON 3VA2 4-pole frames. Front IP40 protection handles the usual panel environment; no washdown rating, so keep it inside the enclosure. Operating temperature range is -40 °C to 70 °C, storage from -40 °C to 80 °C — fine for unheated electrical rooms or outdoor cabinets with heaters.