What this MCCB carries and where it fits
The Siemens SENTRON 3VA1150-6EF32-0KH0 is a 3-pole molded case circuit breaker rated 50 A at 40 °C, designed for line protection in distribution panels. Its breaking capacity hits 220 kA at 240 V AC, 154 kA at 415 V, and 121 kA at 440 V — numbers that tell you it handles high-fault-current service entrances or large secondary substations without cascading upstream. At 500 V and 690 V the rating drops to 17 kA, so keep that in mind for 480 V delta or 600 V class systems: the 440 V figure is the one that governs most North American 480/277 V applications. Rated insulation voltage is 800 V, and the breaker carries a shunt trip (STL) plus two auxiliary switches and one trip alarm switch (HQ). No undervoltage release, no ground-fault monitoring module on this variant — that's a clean line-protection build with remote signaling capability. The trip indicator and voltage trigger are present, so you get local status and a shunt trip for emergency-off or remote tripping schemes. Thermal derating is gradual: 50 A holds through 50 °C, drops to 49 A at 55 °C, 48 A at 60 °C, 46 A at 65 °C, and 45 A at 70 °C. If your panel ambient runs above 50 °C, you lose about 1 A per 5 °C rise — factor that into your continuous load calcs. Maximum power loss is 14.6 W, which is modest for a 50 A frame and won't cook a tightly packed enclosure.
Mounting and integration
Dimensions are 130 mm high, 76.2 mm wide, 70 mm deep — a standard SENTRON 3VA frame footprint. It bolts into a panel or mounts on a mounting plate; no DIN-rail clip on this MCCB class. The supplied basic switch is order code 3VA11506EF320AA0, which is the internal mechanism — you're ordering the complete breaker with that switch, shunt trip, and aux switches pre-assembled. Storage range is -40 °C to 80 °C; operating range is -25 °C to 70 °C.