The Siemens SENTRON 3VA2225-5HN42-0AD0 is a 4-pole molded case circuit breaker (MCCB) rated for 250 A continuous current, built around the ETU350 electronic trip unit. This is a line-protection version — no undervoltage release, no ground-fault monitoring, no communication module — intended for straightforward feeder or main breaker duty in a distribution panel. The 187 kA interrupting rating at 240 V and 121 kA at 415 V place it in the high-fault category for industrial switchboards where available fault current exceeds typical 65 kA or 100 kA MCCB ratings. At 690 V the rating drops to 5.1 kA, so this is not a 690 V main breaker — it lives on the 400–480 V side of the transformer. Current-carrying capacity holds at 250 A from 40 °C through 50 °C (–), then derates to 213 A at 70 °C. In a sealed, uncooled enclosure running at 55 °C ambient, expect 241 A available — close enough to the 250 A nameplate that the breaker can serve a 250 A bus without upsizing, provided the enclosure ventilation keeps internal rise under control.
Sizing and coordination
The ETU350 electronic trip unit offers adjustable long-time, short-time, instantaneous, and ground-fault (if enabled) protection curves. This 3VA2225-5HN42-0AD0 ships without ground-fault monitoring, so the trip unit is configured for phase overcurrent only. The 3 auxiliary switches HQ provide status feedback — useful for remote tripping indication or PLC-driven load shedding. Maximum power loss is 48 W. In a multi-breaker panel, that heat adds up — account for it in the thermal budget when grouping several 250 A frames in a single enclosure. The IP40 front protection means the breaker face is protected against solid objects >1 mm but not against water ingress; keep it inside a gated enclosure, not on an open panel face in a washdown area. Dimensions are 140 mm wide × 181 mm high × 86 mm deep. The 140 mm width is standard for a 4-pole SENTRON 3VA2 frame — it occupies the same footprint as the 3VA2225-5HN42-0BB0 variant, so a panel laid out for the -0BB0 accepts this -0AD0 without drilling new mounting holes or re-routing busbars.
Lifecycle and sourcing
For BOM qualification, the supplied basic switch is listed as 3VA2225-5HN42-0AA0 — that is the internal switching mechanism. When ordering replacement or spare units, the complete order code 3VA2225-5HN42-0AD0 is the procurement line item; the -0AA0 subassembly is not a field-replaceable part stocked separately.