What it is and what the ratings mean
The Siemens SENTRON 3VA2025-6KP32-0AA0 is a 3-pole molded case circuit breaker (MCCB) designed for line protection in distribution panels. Its continuous rated current is 25 A, with an adjustable overload range from 38 A minimum to 300 A maximum — meaning you set the trip threshold to match the protected conductor, not the breaker's own thermal limit. The ETU850 electronic trip unit gives you adjustable long-time, short-time, instantaneous, and ground-fault protection curves, so it can coordinate with downstream breakers in a selective scheme. Breaking capacity is the headline: 242 kA at 240 V, 187 kA at 415 V and 440 V, 121 kA at 500 V, and 3 kA at 690 V. Those numbers mean this breaker can safely interrupt a fault current up to 242,000 A at 240 V without welding contacts or rupturing the case — essential for high-fault service-entrance or industrial main-breaker positions where available fault current is high. Rated insulation voltage is 800 V. The front face carries IP40 protection.
Panel fit and integration
Dimensions are 181 mm high, 105 mm wide, 86 mm deep. It mounts via rear screw terminals or a DIN-rail adapter. Power loss at rated current is 0.84 W maximum — negligible for thermal budgeting inside a sealed enclosure, but worth noting if you're packing a dozen breakers into a small box. The operating temperature range is -25 °C to 70 °C, with storage from -40 °C to 80 °C, so it handles unheated warehouses and outdoor cabinets in most climates. Communication function is built in — the ETU850 supports Modbus RTU over a dedicated communication module (ordered separately), enabling remote trip indication, current metering, and parameter adjustment from a PLC or SCADA. No separate power supply needed for the trip unit; it's self-powered from the line current.