The Siemens 3VA1150-6EF32-0CA0 is a SENTRON molded case circuit breaker (MCCB) rated for line protection in three-phase distribution. It carries a 50 A continuous current (Iu) with a TM240 thermal-magnetic release — the thermal element handles overloads, the magnetic element clears short-circuits. Breaking capacity hits 220 kA at 240 V AC, 154 kA at 415 V, and 121 kA at 440 V, which puts it in the high-interrupting class for industrial mains feeding large MCCs or transformer secondaries where fault current is stiff.
Breaking capacity and selectivity
At 415 V the 154 kA interrupting rating means this breaker can be applied downstream of a transformer with minimal upstream coordination effort — it clears a bolted fault before the main breaker sees it, preserving selectivity. At 690 V the rating drops to 17 kA, so if your line runs 690 V motors, verify the available fault current stays under that threshold. The 800 V rated insulation voltage (Ui) confirms the breaker is built for 690 V systems with margin.
Thermal derating and ambient temperature
The 50 A rating holds flat from 40 °C through 50 °C ambient. 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. If the panel runs hot — say a non-ventilated enclosure next to a furnace line — size the load current against the derated figure, not the nameplate 50 A. Operating range is -25 °C to 70 °C; storage range is -40 °C to 80 °C.
Integrated undervoltage release
This variant ships with an undervoltage release (UVR) as the auxiliary release — part number 3VA9608-0BB24. When line voltage drops below the release threshold, the UVR trips the breaker open. That is standard for applications where a brownout must disconnect loads (conveyor drives, compressors) to prevent re-acceleration surge when power returns. No auxiliary contact is included on this order code; if you need a status signal back to the PLC, add a separate auxiliary switch block.
Mounting and panel fit
The breaker measures 76.2 mm wide (3-pole), 130 mm tall, and 70 mm deep. It mounts to a DIN rail or directly to a backplate via screw terminals. The IP40 front protection means the breaker face is sealed against tools and fingers — standard for enclosed panel mounting. No communication function, no phase-failure detection, no ground-fault monitoring on this variant; it is a pure thermal-magnetic line protection device.