Siemens SENTRON 3VA1140-5EF36-0CC0 — 40 A MCCB for Line Protection
The Siemens SENTRON 3VA1140-5EF36-0CC0 is a 3-pole molded case circuit breaker rated for 40 A continuous at 40 °C, designed specifically for line protection in distribution panels. It carries a 121 kA breaking capacity at 415 V, which means it can safely interrupt fault currents up to that level without cascading upstream — critical for maintaining selectivity in a multi-level distribution scheme. The unit ships with an integrated undervoltage release (UVR) and two HQ auxiliary switches, so it arrives ready for remote status indication and undervoltage tripping without adding separate modules.
Breaking Capacity & Thermal Performance
Breaking capacity drops with system voltage: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 500 V and 690 V. The 415 V figure is the one that matters for most European 400 V distribution — 121 kA puts this breaker in the high-fault category, suitable for transformer-secondaries and main switchboards. Thermal derating is minimal up to 50 °C (flat 40 A), then drops to 39 A at 55 °C and 37 A at 70 °C. Rated insulation voltage is 800 V, giving headroom for 690 V systems.
Built-In Auxiliaries & Release
The 3VA1140-5EF36-0CC0 includes two HQ auxiliary switches (form C) for status feedback to a PLC or panel indicators, plus an undervoltage release (UVR) that trips the breaker when control voltage drops below dropout threshold. No communication function onboard — this is a plain breaker, not a smart metering unit. The UVR is factory-fitted; verify coil voltage rating against your control supply before panel wiring. Power loss is 13.3 W maximum at rated load, which matters for enclosure thermal calculations in sealed cabinets.