The Siemens SENTRON 3VA2340-7HN32-0AG0 is a 3-pole molded case circuit breaker rated for 400 A continuous current, designed for line protection in distribution panels. Its interrupting capacity hits 330 kA at 240 V, 242 kA at 415/440 V, 187 kA at 500 V, and 7.5 kA at 690 V — so it handles high-fault scenarios downstream of a transformer or generator feed without cascading upstream.
Thermal derating and panel fit
The breaker holds full 400 A from 40 °C up to 50 °C ambient. Above that it derates: 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. If your panel runs hot — say a packed enclosure with drives — size the upstream feeder for the derated value at your actual ambient, not the nameplate 400 A. Dimensions are 248 mm high, 138 mm wide, 110 mm deep. That 138 mm width is a standard 3-pole MCCB footprint for a SENTRON frame; verify the gland-plate cutout and busbar spacing against your existing panel layout before committing the BOM line.
Auxiliary switching and power loss
The breaker ships with one auxiliary switch and one trip alarm switch (HP type) built in — enough for remote status indication without adding an external accessory block. Maximum power loss is 96 W at rated load; factor that into your enclosure thermal budget if the panel is sealed or tightly packed. Operating range spans -25 °C to 70 °C, storage from -40 °C to 80 °C.