What this MCCB carries and where it fits
The Siemens SENTRON 3VA2225-5HL32-0KA0 is a 3-pole molded case circuit breaker rated for 250 A continuous current (Iu) at 40 °C, with the ETU320 electronic trip unit configured for line protection. Its breaking capacity reaches 187 kA at 240 V and 121 kA at 415 V, so it handles high-fault utility feeds or transformer secondaries where the available short-circuit current is substantial. The 86 mm depth and 105 mm width fit standard MCCB panel footprints — no special adapter plate needed for most distribution boards.
Current rating and thermal derating — the real usable capacity
Full 250 A holds through 50 °C ambient. At 55 °C it derates to 241 A, at 60 °C to 232 A, at 65 °C to 222 A, and at 70 °C to 213 A. If the panel runs hot — say a compact switchgear lineup with multiple breakers — the 55 °C column is the one that governs the load schedule. The maximum power loss is 48 W, which matters for enclosure heat rise calculations when grouping several breakers.
Trip unit and auxiliary release configuration
The ETU320 overcurrent release provides electronic trip curves for line protection — no ground-fault monitoring, no phase-failure detection, no communication module. The shunt trip (STL) is built in for remote tripping; the integrated auxiliary trip is order code 3VA9688-0BL33. No auxiliary contact version is fitted, and there is no undervoltage release. The supplied basic switch is 3VA2225-5HL32-0AA0.
Environmental limits and endurance
Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The latching endurance is rated at 20 000 operations — adequate for distribution duty where the breaker is not cycled daily. Rated insulation voltage is 800 V, so it is suitable for 690 V systems with margin.