What this MCCB carries and where it fits
The Siemens SENTRON 3VA2225-8HL32-0HA0 is a 3-pole molded case circuit breaker rated for 250 A continuous current at 40 °C, designed for line protection in distribution panels. Its interrupting capacity reaches 440 kA at 240 V and 330 kA at 415 V, so it handles high-fault scenarios typical of industrial mains or large sub-distribution boards. The integrated shunt trip (STL) allows remote tripping via a control signal — useful for emergency-stop circuits or supervisory system override.
Derating and thermal management
At 40 °C, 45 °C, and 50 °C the breaker holds its full 250 A rating. Above 50 °C it derates linearly: 241 A at 55 °C, 232 A at 60 °C, 222 A at 65 °C, and 213 A at 70 °C. Maximum power loss is 48 W. In a sealed enclosure with multiple breakers ganged, factor the ambient rise into your load schedule — the 70 °C ceiling is the operating limit, not a safety margin.
Dimensions and panel integration
The breaker measures 105 mm wide, 181 mm high, and 86 mm deep. Mounts on a standard DIN rail or direct panel. The 86 mm depth leaves clearance behind most enclosure gland plates — verify against your backpanel depth if the breaker sits near the door. Width of 105 mm for a 3-pole frame is compact for the 250 A class; adjacent breakers or busbar shroud clearance should follow Siemens' specified side gap (typically 0–10 mm, per the installation instructions).