The Siemens 3VA1150-5EF32-0AD0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection in commercial and industrial distribution panels. It carries a 50 A continuous rating at 40 °C and a 187 kA interrupting capacity at 240 V — the full short-circuit rating at the most common low-voltage fault level, so it clears high-energy faults without cascading upstream.
Ratings and what they mean for fit
Rated 50 A across the 40–50 °C range, derating to 45 A at 70 °C — the thermal-magnetic TM240 release holds the continuous load curve without nuisance tripping in a warm enclosure. Three-pole construction suits three-phase feeders, motor branch circuits, or main disconnects in a panelboard. Interrupting capacity steps down with voltage: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at 500/690 V. That 187 kA figure at 240 V is the one that governs most North American 480Y/277 V panel applications where the available fault current exceeds 100 kA — this breaker handles it without an upstream current-limiting fuse. Rated insulation voltage 800 V, so the breaker is electrically rated for 690 V systems with margin. The TM240 release is a fixed thermal-magnetic type — no interchangeable trip unit, which simplifies spares but means the breaker is dedicated to the 50 A rating.
Deployment context
Mounts on a standard DIN rail or panel-mount footprint. The 70 mm depth and 76.2 mm width fit a 3-pole MCCB slot in most SENTRON distribution boards. Three auxiliary switches HQ are built in — no separate accessory wiring needed for status feedback to a PLC or remote monitoring system.