What it is and what it does
The Siemens SENTRON 3VA1150-3EF32-0JH0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection. It carries a rated current of 50 A at 40 °C, with a breaking capacity of 75.6 kA at 240 V — enough to safely clear high-fault currents in industrial distribution panels without cascading upstream.
Key ratings and what they mean
The 50 A rating holds steady from 40 °C up to 50 °C, then derates to 49 A at 55 °C and 45 A at 70 °C — a thermal curve that matters if this breaker sits in a warm enclosure or near other heat sources. Breaking capacity drops with voltage: 52.5 kA at 415 V, 32 kA at 440 V, and 11.9 kA at 500 V or 690 V. That 11.9 kA floor at 690 V still covers most industrial fault levels, but verify your available fault current at the installed voltage before committing the BOM line.
Where it goes in the panel
The 3VA1150-3EF32-0JH0 measures 130 mm high, 76.2 mm wide, and 70 mm deep — a standard SENTRON MCCB footprint that bolts into a distribution panel or switchboard. It ships with a shunt trip (STL) and two auxiliary switches plus one trip alarm switch, so you can wire remote tripping and status feedback without adding external relays.