What this MCCB delivers
The Siemens SENTRON 3VA1150-5EF32-0DA0 is a 3-pole molded case circuit breaker (MCCB) rated for line protection, carrying a continuous current Iu of 50 A and an interrupting capacity of 187 kA at 240 V AC. That 187 kA figure at 240 V means it can safely clear a fault up to that level without upstream devices needing to intervene — critical for high-fault panels near large transformers or busway taps. At 415 V the rating is 121 kA, at 440 V it is 75.6 kA, and at 690 V it drops to 17 kA; the interrupting capacity is voltage-dependent, so the buyer must match the available fault current at the point of installation. The overcurrent release is a TM240 thermal-magnetic unit — the thermal element handles overloads, the magnetic element handles short-circuits. There is no electronic trip unit, no communication function, and no phase-failure detection; this is a straightforward, non-communicating MCCB for conventional distribution. An undervoltage release (UVR) is integrated (order code 3VA9608-0BB25 for the auxiliary trip), which allows remote or emergency-off tripping by dropping the coil voltage. Thermal derating is minimal up to 50 °C — the breaker holds 50 A at 40, 45, and 50 °C. At 55 °C it derates to 48 A, at 60 °C to 47 A, at 65 °C to 46 A, and at 70 °C to 45 A. For a panel running at 50 °C ambient, the full 50 A is available; above that, the continuous load must be reduced per the curve.
Panel fit and footprint
The 3VA1150-5EF32-0DA0 measures 130 mm high, 76.2 mm wide, and 70 mm deep. The 76.2 mm width (3-inch pitch) matches the standard SENTRON 3VA frame spacing for 3-pole breakers; it mounts on a DIN rail or directly to a backplate via the screw terminals. IP40 on the front means it is protected against tools and wires larger than 1 mm — fine for a dry indoor panel, but not for washdown or outdoor installation.