This MCCB delivers 187 kA breaking capacity at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V. At a typical 480Y/277 V industrial service, the 121 kA figure gives substantial SCCR headroom for high-fault panels — useful when coordinating with upstream transformers or downstream branch breakers. The 250 A frame size and 3-pole construction suit main or feeder protection in switchboards and motor control centers.
Temperature derating and thermal management
The 250 A rating holds flat from 40 °C through 50 °C, then derates to 240 A at 55 °C, 235 A at 60 °C, 230 A at 65 °C, and 225 A at 70 °C. In a crowded panel with multiple breakers side-by-side, expect to apply the 60 °C or 65 °C figure if ambient inside the enclosure runs high — the 37.5 W maximum power loss per pole contributes to internal heat rise, so verify fill factor and ventilation against the installed derating curve.
At 248 mm high, 138 mm wide, and 110 mm deep, this 3-pole MCCB fits standard SENTRON 3VA2 mounting footprints. The 138 mm width matches other 250 A frame 3-pole units in the family.