The Siemens SENTRON 3VA1150-5EF36-0KA0 is a 3-pole molded case circuit breaker (MCCB) rated for 50 A continuous current. It carries a TM240 thermal-magnetic overcurrent release and includes an integrated shunt trip (STL) for remote tripping. Breaking capacity reaches 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 690 V — the 415 V figure is the one that governs most 400 V-class distribution panels. Rated insulation voltage is 800 V, and the breaker is designed for line protection in commercial and industrial switchboards. Front protection is IP40; the enclosure is sized at 130 mm height, 76.2 mm width, and 70 mm depth — a standard 3-pole MCCB footprint that fits most SENTRON panelboards without re-drilling.
Thermal derating and ambient limits
The 50 A rating holds flat from 40 °C through 50 °C. Above that, the breaker derates: 48 A at 55 °C, 47 A at 60 °C, 46 A at 65 °C, and 45 A at 70 °C. If the panel ambient runs near 60 °C, plan for a 3 A reduction — or step up one frame size if the load is continuous at 50 A. Operating range is -25 °C to +70 °C; storage range is -40 °C to +80 °C.
Integrated shunt trip and auxiliary provisions
This variant ships with a factory-integrated shunt trip (STL) — design order code 3VA9688-0BL33 — for remote opening via a control voltage. No undervoltage release, no auxiliary contact, and no communication module are fitted. The breaker has a voltage trigger (shunt trip) but no phase-failure detection or ground-fault monitoring. Mechanical endurance is rated at 15,000 operations.