What this 250 A MCCB carries
The Siemens SENTRON 3VA1225-5GF42-0CC0 is a 4-pole molded case circuit breaker rated for 250 A continuous at 40 °C, with the same 250 A hold up through 50 °C before derating begins — 243 A at 55 °C, 237 A at 60 °C, 230 A at 65 °C, 223 A at 70 °C. That thermal curve means it can sit in a warm panel without losing headroom until the ambient crosses 50 °C. Interrupting capacity is 187 kA at 240 V, 121 kA at 415 V, 75.6 kA at 440 V, 30 kA at 500 V, and 17 kA at 690 V — so it handles high-fault utility feeds at low voltage and still clears substantial faults at 690 V. Rated insulation voltage is 800 V. This is a line-protection design (not feeder or motor-protection pattern), fitted with an undervoltage release (UVR) as the auxiliary release and two HQ auxiliary switches. No ground-fault monitoring, no communication function, no voltage trip trigger.
Panel fit and integration
Dimensions are 70 mm deep, 140 mm wide, 158 mm tall — a standard 4-pole MCCB footprint for DIN-rail or panel-mount enclosures. The 70 mm depth keeps it within typical gland-plate clearance on a 200 mm deep cabinet. Power loss at full load is 59.5 W maximum — factor that into enclosure thermal calculations if the panel is sealed or densely populated.