MCCB for line protection — 50 A frame, high interrupting capacity
The Siemens SENTRON 3VA1050-4ED36-0HC0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection in distribution panels. Rated 50 A continuously at 40 °C, it holds that rating through 50 °C and derates to 45 A at 70 °C — useful when the breaker shares a warm enclosure with other heat sources. The interrupting capacity is the headline: 121 kA at 240 V, 75.6 kA at 415 V, and still 11.9 kA at 690 V, so it handles high-fault utility feeds or transformer secondaries without cascading upstream. The 800 V rated insulation voltage confirms it is built for 690 V systems with margin.
Sizing and thermal behaviour in the panel
The frame measures 130 mm high, 76.2 mm wide, and 70 mm deep — a standard 3-pole MCCB footprint that fits most Siemens SENTRON distribution boards and third-party enclosures with DIN-rail or screw-mount adapters. Maximum power loss is 14.6 W, which matters for thermal calculations in sealed enclosures. Operating range spans -25 °C to 70 °C, with storage from -40 °C to 80 °C. The shunt trip release (STL) is built in, allowing remote tripping from a safety circuit or emergency-stop button.