MCCB for high-fault line protection
The Siemens SENTRON 3VA1225-6GF42-0KH0 is a 4-pole molded case circuit breaker rated 250 A continuous, designed for line protection in distribution panels. Its interrupting capacity hits 220 kA at 240 V, 154 kA at 415 V, and still delivers 17 kA at 690 V — meaning it can clear high-energy faults upstream without cascading to downstream gear. The 800 V rated insulation voltage supports 690 V line-to-line systems with headroom. Thermal derating is minimal up to 50 °C (still 250 A), then drops to 243 A at 55 °C and 223 A at 70 °C. That matters if this breaker sits in a non-climate-controlled enclosure near transformers or drives. The 57 W maximum power loss is the heat you need to vent — factor it into the enclosure sizing calculation.
Auxiliaries and releases
Factory-fitted with 2 auxiliary switches plus 1 trip alarm switch (HQ type) and a shunt trip release (STL). The shunt trip allows remote tripping from an E-stop or safety relay — common for emergency-off circuits. No undervoltage release and no ground-fault monitoring on this variant, so if you need UVR or GF protection, you're looking at a different suffix.
Dimensions and panel fit
Footprint is 140 mm wide × 158 mm tall × 70 mm deep. That's a standard 4-pole MCCB envelope for this current class — mounts on a DIN rail or directly to a backplate via the screw terminals. The 70 mm depth keeps it within typical 200 mm deep enclosure clearance.