What it is and what the ratings mean
The Siemens SENTRON 3VM1150-3EE32-0AA0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection in distribution panels. Its TM220 thermal-magnetic release combines a thermal bimetal for overloads and a magnetic coil for short circuits — the 220 frame size indicates a 50 A continuous rating at 40 °C. That 50 A holds flat up to 50 °C; above that, the thermal curve derates to 49 A at 55 °C, 48 A at 60 °C, and 45 A at 70 °C. For a buyer sourcing this into a warm enclosure, the 70 °C derated value is the one that governs the real load. The interrupting ratings cover the common industrial voltage tiers: 76 kA at 240 V AC, 53 kA at 415 V, 32 kA at 440 V, and 12 kA at 500 V. That 53 kA at 415 V is the figure that matters for most European and Asian 400 V-class panels — it determines whether this breaker coordinates with upstream gear or needs a current-limiting device ahead of it. Rated insulation voltage is 800 V. Power loss at rated load is 15 W maximum.
Panel fit and integration
Dimensions: 70 mm deep, 76.2 mm wide, 130 mm tall. The 76.2 mm width (3 inches) is a standard 3-pole MCCB footprint — it fits most DIN-rail or panel-mount enclosures without re-drilling. Front protection class is IP40, meaning tools and fingers are kept out but the unit is not sealed against washdown; install in a dry indoor panel. No undervoltage release, no shunt trip, no communication function on this variant — it is a straight thermal-magnetic breaker for hardwired distribution.