What the ratings mean for your panel
The Siemens SENTRON 3VA2225-7KP32-0KH0 is a 3-pole molded case circuit breaker (MCCB) rated for a continuous current Iu of 250 A, with an interrupting capacity of 330 kA at 240 V AC — that is the fault current it can safely clear without welding contacts or rupturing the housing, which matters for high-fault utility or transformer-fed service entrances. At 415 V and 440 V the interrupting rating drops to 242 kA, and at 690 V it is 6.3 kA — the voltage derating is steep, so verify the available fault current at your system voltage before specifying. The ETU850 electronic trip unit provides adjustable long-time, short-time, instantaneous, and ground-fault protection curves — this is a fully programmable trip, not a fixed thermal-magnetic, so coordination studies can be tuned without swapping the breaker.
Integration dimensions and auxiliaries
The breaker measures 105 mm wide, 181 mm high, and 86 mm deep — it fits standard MCCB panel cutouts and busbar spacing for a 250 A frame. The auxiliary contact configuration is 2 auxiliary switches plus 1 trip alarm switch (HQ), and a shunt trip (STL) is integrated as the auxiliary release. The supplied basic switch is order code 3VA2225-7KP32-0AA0, and the integrated auxiliary trip is 3VA9688-0BL33 — these are the internal sub-assemblies, not field-replaceable by the end user, but useful for spares planning if the breaker is part of a larger SENTRON family panel.
Thermal derating and ambient limits
The breaker carries its full 250 A rating from 40 °C through 50 °C ambient. Above 50 °C it derates linearly: 238 A at 55 °C, 225 A at 60 °C, 213 A at 65 °C, and 200 A at 70 °C. The maximum operating ambient is 70 °C, minimum -25 °C. Maximum power loss is 48 W — account for this in enclosed panel heat calculations, especially when multiple breakers are ganged in a single enclosure.