SENTRON 3VA2 – 250 A line protection with ETU320
The Siemens SENTRON 3VA2325-6HL42-0AA0 is a 4-pole molded case circuit breaker rated for 250 A continuous current (Iu). It carries an ETU320 electronic trip unit, making it a line-protection device suited for main feeders or large sub-distribution in commercial and industrial switchboards. Breaking capacity is voltage-dependent: 242 kA at 240 V AC, 187 kA at both 415 V and 440 V, 121 kA at 500 V, and 7.5 kA at 690 V. The 187 kA at 415 V is the figure most European industrial panels will care about — it handles high-fault utility feeds without cascading upstream. Rated insulation voltage (Ui) is 800 V. N-conductor protection is adjustable: OFF, 50%, or 100% of the phase rating.
Thermal derating and panel fit
The 250 A rating holds flat across the full ambient range from 40 °C through 70 °C — no derating needed for typical enclosed panel temperatures. That is unusual; many MCCBs start tapering above 40 °C. The 3VA2 keeps its full 250 A up to 70 °C, which simplifies coordination studies in hot environments. Operating temperature range is -25 °C to +70 °C; storage from -40 °C to +80 °C. Front protection is IP40 — fine for indoor switchgear but not washdown zones. Dimensions: 248 mm high, 184 mm wide, 110 mm deep. The 184 mm width is the 4-pole frame; verify the panel cutout matches before committing the BOM line. Maximum power loss is 37.5 W — a figure to factor into enclosure thermal calculations, especially in multi-breaker assemblies.