What it is and what it does
The Siemens SENTRON 3VA1150-3EF36-0JA0 is a 3-pole molded case circuit breaker (MCCB) sized for line protection, rated 50 A at 40 °C and carrying a shunt trip (STL) auxiliary release. Its interrupting capacity hits 75.6 kA at 240 V and 52.5 kA at 415 V, so it can handle high-fault scenarios without cascading upstream — a solid fit for main or feeder breakers in a distribution panel where SCCR coordination matters.
Key ratings and what they mean for fit
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. If your panel runs hot — say a sealed enclosure near a motor drive — that thermal curve is what you check against the actual load. The TM240 overcurrent release is a thermal-magnetic type, meaning it handles overloads thermally and short-circuits magnetically, no electronic adjustment.
Mounting and integration
The breaker measures 70 mm deep by 76.2 mm wide by 130 mm high — a standard MCCB footprint that bolts into a panel or mounts on a mounting plate. The shunt trip (STL) lets you remotely trip the breaker via a control voltage; wire it to an emergency-stop relay or a safety PLC output for a clean kill on the line.