What this MCCB delivers in the panel
The Siemens 3VA1150-5EF32-0HC0 is a SENTRON 3-pole molded case circuit breaker rated for 50 A continuous current across ambient temperatures up to 50 °C, with a 1 A derating step at 55 °C and a floor of 45 A at 70 °C. That thermal profile means it holds full rating in most ventilated enclosures; only tight cabinets or high-ambient zones force a down-rate. Breaking capacity is the headline: 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, and 17 kA at both 500 V and 690 V. That 187 kA figure at 240 V puts it well into high-fault-current territory — think transformer secondaries or large motor control centers where upstream fault current is severe. The 17 kA floor at 690 V still covers most industrial distribution. Rated insulation voltage is 800 V, giving headroom on 690 V systems. The breaker ships with a shunt trip release (STL) and two auxiliary switches HQ built in — no separate ordering for basic alarm and status feedback. The line-protection design means it's tuned for cable and busbar protection, not motor overload curves.
Integration and mounting
Dimensions are 130 mm height, 76.2 mm width, 70 mm depth — a standard 3-pole MCCB footprint that fits most DIN-rail or panel-mount enclosures. The 76.2 mm width (3 inches) is the typical 3-pole pitch; verify busbar spacing if retrofitting into an existing distribution block. Power loss is 14.6 W maximum — relevant for thermal budgeting inside sealed enclosures. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C.