Siemens SENTRON 3VA2225-5HN32-0KH0 — 250 A MCCB for Line Protection
The Siemens SENTRON 3VA2225-5HN32-0KH0 is a 3-pole molded case circuit breaker rated for 250 A continuous current at 40 °C, designed for line protection in distribution panels. Its interrupting capacity reaches 187 kA at 240 V and 121 kA at 415 V, which means it can safely clear high-fault currents without cascading upstream — critical for main feeders or high-capacity branch circuits where available fault current is substantial.
Thermal Derating and Operating Range
The breaker holds its full 250 A rating up to 50 °C ambient. Above that, derating is linear: 241 A at 55 °C, 232 A at 60 °C, 222 A at 65 °C, and 213 A at 70 °C. If the panel runs warm — say, near a transformer or in a non-conditioned enclosure — size the load against the derated figure, not the 40 °C nameplate. Operating temperature range is -25 °C to 70 °C; storage range is -40 °C to 80 °C. The storage limit governs handling and warehousing, not running conditions.
Interrupting Capacity by Voltage Level
Interrupting capacity drops with system voltage: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 4.5 kA at 690 V. The 690 V figure is notably lower — verify available fault current if applying on a 690 V line; this breaker is not intended for high-fault 690 V main service.
Integrated Auxiliary and Trip Functions
Factory-fitted with 2 auxiliary switches plus 1 trip alarm switch (HQ configuration), and a shunt trip (STL) for remote tripping. No undervoltage release is included. The trip indicator and voltage trigger are present, giving visual and electrical status feedback for PLC or SCADA monitoring.