Siemens SENTRON 3VA2225-8KQ32-0AA0 — 250 A MCCB with Communication
The Siemens SENTRON 3VA2225-8KQ32-0AA0 is a 3-pole molded case circuit breaker (MCCB) rated for 250 A continuous current at 40 °C, designed for line protection in distribution panels. It carries a breaking capacity of 440 kA at 240 VAC and 330 kA at 415 VAC, so it handles high-fault scenarios typical in industrial mains or sub-distribution boards without cascading upstream. The built-in communication function and ground-fault monitoring via summation current formation mean this breaker can report status and fault data to a BMS or PLC — a key differentiator from a standard thermal-magnetic MCCB.
Thermal Derating and Real-World Current Capacity
The 250 A rating holds from 40 °C to 50 °C. Above that, it derates linearly: 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C (–). For a panel with ambient near 60 °C — say, a packed enclosure next to a furnace line — the effective continuous current drops to 225 A. The 48 W maximum power loss is the heat the breaker dumps into the enclosure; factor that into the thermal budget.
Breaking Capacity Across Voltage Tiers
The interrupting ratings span the voltage range: 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 (–). At 690 V the breaker still clears 52.5 kA — enough for most 690 V industrial drives or mining distribution. The insulation voltage is rated 800 V, so the breaker is electrically safe for 690 V line-to-line systems.
Trip Unit and Adjustability
Trip unit minimum setting is 375 A, maximum is 2,500 A, full-scale value is 250 A.
Physical Fit and Mounting
Dimensions: 181 mm height, 105 mm width, 86 mm depth.
Environmental and Operating Range
Operates from -25 °C to 70 °C. Storage range is -40 °C to 80 °C — that wider storage window governs handling and warehousing, not running conditions. The breaker is designed for line protection, meaning it protects cables and busbars against overload and short circuit, not motor or generator protection.