What it is and what it does
The Siemens 3VA2325-8KQ42-0AA0 is a SENTRON molded case circuit breaker (MCCB) built for line protection in industrial power distribution. It carries a continuous current rating of 250 A that holds flat from 40 °C all the way up to 70 °C — no derating needed in a warm cabinet (–). That's unusual for an MCCB and means you don't have to oversize the frame or add forced cooling when the panel runs hot. The 4-pole configuration covers three-phase plus neutral, with the N-conductor protection adjustable from OFF to 20–160% of the phase rating. That's handy for panels where the neutral load isn't symmetrical — common in VFD-fed lines or lighting distribution.
Breaking capacity — what the numbers mean for your fault level
This breaker's interrupting ratings span the voltage range you'll see in most industrial switchgear: 440 kA at 240 V, 330 kA at 415 V and 440 V, 220 kA at 500 V, and 52.5 kA at 690 V. The 690 V figure is the one to watch — if your system's available fault current at the line side exceeds 52.5 kA at that voltage, this breaker isn't the right choice. For typical 480 V北美 panels, the 220 kA at 500 V rating gives comfortable headroom even on high-capacity transformers.
Trip unit and adjustability
The ETU860 electronic trip unit is the brains here — it's adjustable for I-trip, giving you selectivity tuning without swapping trip packs. The ground-fault monitoring uses summation current formation on L+N, which is the standard approach for 4-pole breakers protecting solidly-grounded systems. Communication function is built in, so this breaker can talk to a BMS or PLC for power monitoring and remote trip indication — no separate module needed.
Physical fit and environment
Dimensions: 248 mm tall, 184 mm wide, 110 mm deep (–). That's a standard 4-pole MCCB footprint — it'll drop into most SENTRON or competitor panel-mounting bases without re-drilling. Front protection is IP40, meaning it's fine in a closed panel but not for washdown areas. Operating range is -25 °C to 70 °C (–); storage range is -40 °C to 80 °C (–). Power loss maxes at 37.5 W — negligible for cabinet heat load.