SENTRON 3VA1225-6EF42-0CC0 — 250 A, 4-Pole Molded Case Circuit Breaker for Line Protection
The Siemens SENTRON 3VA1225-6EF42-0CC0 is a 4-pole molded case circuit breaker (MCCB) rated at 250 A at 40 °C, designed for line protection in distribution panels. Its 220 kA breaking capacity at 240 V means it can safely interrupt fault currents up to that level without upstream damage — critical for high-fault installations like transformer secondaries or large motor control centers. The breaker includes an undervoltage release (UVR) and two auxiliary switches HQ, giving the panel builder integrated status feedback and trip signaling without external add-ons.
Breaking Capacity and Thermal Derating
Breaking capacity drops from 220 kA at 240 V to 154 kA at 415 V, 75.6 kA at 440 V, 30 kA at 500 V, and 17 kA at 690 V — a steep curve that matters when specifying for 480 V or 600 V systems. The 250 A rating holds flat from 40 °C to 50 °C, then derates to 243 A at 55 °C and 230 A at 65 °C. For a panel running at 60 °C ambient, the usable current is 237 A, not the full 250 A. The 800 V rated insulation voltage confirms suitability for 690 V line-to-line systems.
Panel Integration and Dimensions
Footprint is 140 mm wide by 158 mm tall by 70 mm deep — a standard 4-pole MCCB envelope that fits most DIN-rail or panel-mount enclosures. The 59.5 W maximum power loss means the breaker dissipates heat into the enclosure; factor that into thermal calculations for sealed cabinets. Operating temperature range is -25 °C to 70 °C, storage from -40 °C to 80 °C.