Siemens SENTRON 3VA2225-5HN42-0JC0 — 250 A MCCB with ETU350
The Siemens 3VA2225-5HN42-0JC0 is a 4-pole SENTRON molded case circuit breaker rated for 250 A continuous current. It carries an interrupting capacity of 187 kA at 240 V, stepping down to 121 kA at 415 V and 440 V, then 79 kA at 500 V, and 5.1 kA at 690 V — that spread tells you it's sized for high-fault utility feeds at low voltage, not for 690 V distribution. The ETU350 electronic trip unit gives you adjustable long-time, short-time, and instantaneous protection curves, plus a shunt trip (STL) for remote opening. Two high-performance auxiliary switches (HQ) are integrated for status feedback to the PLC or SCADA system.
What the interrupting ratings mean for coordination
At 240 V this breaker clears 187 kA symmetrical — that's a utility-side fault level typical of a large transformer secondary or a generator bus. At 415/440 V it still holds 121 kA, which covers most industrial switchboards. The drop to 79 kA at 500 V and 5.1 kA at 690 V is expected for a frame this size; if your system runs 690 V and fault current exceeds that, you need a higher-rated frame. The 800 V rated insulation voltage (Ui) means the internal clearances are designed for 690 V line-to-line systems.
Thermal derating and panel integration
The 250 A rating holds flat from 40 °C to 50 °C ambient. At 55 °C it derates to 241 A, then 232 A at 60 °C, 222 A at 65 °C, and 213 A at 70 °C. If this breaker sits in a crowded enclosure with other heat sources, plan your thermal budget around the 48 W maximum power loss. The 140 mm width, 181 mm height, and 86 mm depth fit standard SENTRON mounting patterns — it drops into the same cutout as other 3VA2 frames, so a panel laid out for a 3VA2225-5HN42-0BB0 takes this unit without re-drilling.
Protection and control features
The ETU350 electronic trip unit provides LSIG protection (long-time, short-time, instantaneous, ground-fault) with adjustable settings. The shunt trip (STL) allows remote tripping from a safety relay or emergency-stop circuit. Two HQ auxiliary switches report breaker position — one for open/closed status, the second for trip indication. There is no undervoltage release, no communication module, and no phase-failure detection on this variant; those are available on other order codes in the 3VA2 family if your spec requires them.