What this MCCB is and what it does
The Siemens 3VA2225-6HL32-0AB0 is a SENTRON molded case circuit breaker (MCCB) designed for line protection — meaning it sits at the incoming feeder or main distribution point, not downstream on a motor or branch circuit. Its 250 A continuous current rating at 40 °C holds flat through 50 °C, then derates to 213 A at 70 °C. That thermal stability matters when the breaker lives in a warm enclosure with other dissipating gear. Three poles handle three-phase systems. The interrupting capacity climbs to 242 kA at 240 V and stays at 187 kA through 440 V — that's serious fault-clearing for a 250 A frame. At 690 V it drops to 4.5 kA, so confirm system voltage if you're feeding a 690 V bus.
Sizing and thermal derating
The 250 A rating is the nominal at 40 °C ambient. At 55 °C it's still 241 A; at 60 °C it's 232 A; at 65 °C it's 222 A; at 70 °C it's 213 A. If your panel ambient runs above 50 °C, size the load accordingly — the breaker won't nuisance-trip, but you lose headroom. Maximum power loss is 48 W. That's the heat it dumps into the enclosure at full rated current — factor that into your thermal budget if the panel is sealed or has limited airflow.
Physical fit and auxiliary options
Dimensions: 86 mm deep, 105 mm wide, 181 mm high. That's a standard 3-pole MCCB footprint for the 250 A SENTRON frame. It ships with two HP auxiliary switches pre-installed — no separate order needed for basic status feedback. No undervoltage release, no ground-fault monitoring, no communication module. The basic switch variant is 3VA2225-6HL32-0AA0 — the -0AB0 adds the auxiliary switches.