The Siemens 3VA2225-5HN32-0HH0 is a SENTRON molded case circuit breaker (MCCB) rated for line protection, with a continuous current Iu of 250 A across three poles. The interrupting capacity is 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 — figures that govern its application at the main distribution point or as a feeder breaker in a high-fault-current installation. The ETU350 electronic trip unit provides adjustable overload and short-circuit protection curves, with a trip indicator for visual fault confirmation.
Rating and thermal derating
The 250 A rating holds at ambient temperatures up to 50 °C. Above that, the breaker must be derated: 241 A at 55 °C, 232 A at 60 °C, 222 A at 65 °C, and 213 A at 70 °C. For a panel enclosure that runs warm — say 55 °C internal ambient — the usable current drops to 241 A, which may affect coordination with downstream loads. The maximum power loss is 48 W, relevant for thermal calculations inside a sealed cabinet.
Physical integration and auxiliary contacts
Dimensions are 105 mm wide, 181 mm high, and 86 mm deep. The width determines the DIN-rail or mounting-plate footprint in a multi-breaker lineup. The breaker ships with 2 auxiliary switches plus 1 trip alarm switch (HQ configuration), which can be wired into a PLC or status-indication circuit without adding a separate accessory block. The front face carries an IP40 protection class — suitable for a clean dry panel interior, but not for washdown or outdoor exposure without an additional enclosure.