SENTRON 3VA2 — 250 A, 4-Pole MCCB for Line Protection
The Siemens 3VA2225-8KQ42-0AA0 is a SENTRON molded case circuit breaker (MCCB) rated for 250 A continuous current in a 4-pole configuration, designed specifically for line protection. It carries a full-scale value of 250 A with an initial setting of 50 A, covering feeder and main distribution applications in LV switchgear. Interrupting capacity is the headline here: 440 kA at 240 V AC, 330 kA at 415/440 V, 220 kA at 500 V, and 52.5 kA at 690 V. That 440 kA figure at 240 V handles high-fault utility or transformer secondary conditions without cascading upstream — critical for coordination studies in industrial plants where SCCR headroom is tight. Thermal derating is published across the operating range: full 250 A up to 50 °C, then 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. If the panel ambient runs above 50 °C, the continuous load must be trimmed accordingly — the 200 A floor at 70 °C still covers most motor control center feeder duties. Ground-fault monitoring uses summation current formation on L + N conductors, so it detects residual fault current without a separate GFCI module. Communication function is onboard, enabling integration with higher-level monitoring systems for selective coordination and event logging.
Lifecycle & Sourcing
Maximum power loss is 48 W under rated load, which factors into enclosure thermal calculations — not a selection parameter but relevant for panel ventilation planning in sealed cabinets. Dimensions: 181 mm height × 140 mm width × 86 mm depth (7.13 × 5.51 × 3.39 in).
Integration & Environment
Operating temperature range is -25 °C to +70 °C, with storage from -40 °C to +80 °C. The 70 °C operating ceiling matches the derated current of 200 A at that limit — the breaker runs but needs the derating applied. Rated insulation voltage is 800 V, suitable for 690 V AC systems. No undervoltage release or voltage trip is fitted on this variant — the trip indicator is also absent. These are optional accessories in the 3VA2 family; if UVR or trip-flag indication is required for the application, the -8KQ42-0AA0 suffix doesn't include them.