The Siemens SENTRON 3VA2450-5MN32-0DH0 is a 3-pole molded case circuit breaker (MCCB) rated for motor protection duty, carrying a continuous current Iu of 500 A at 40 °C. It uses the ETU350M electronic overcurrent release, which provides adjustable protection curves for motor starting inrush and overload profiles — the kind of coordination you need when a pump or compressor hits locked-rotor current without nuisance tripping the feeder. Breaking capacity runs from 187 kA at 240 V down to 17 kA at 690 V, with 121 kA at both 415 V and 440 V. That SCCR headroom covers most industrial distribution panels where fault current at the main lug is high, and the 800 V rated insulation voltage (Ui) keeps it comfortable on 480 V and 600 V class systems.
Integration & Panel Fit
Dimensions are 248 mm high × 138 mm wide × 110 mm deep. That 138 mm width is the standard 3-pole MCCB footprint for this frame size — it drops into the same DIN-rail or panel-mount cutout as other SENTRON 3VA2 breakers of similar rating. The unit ships with 2 auxiliary switches plus 1 trip alarm switch (HQ configuration), which covers status feedback to a PLC or remote I/O without adding a separate auxiliary block. An undervoltage release (UVR) is integrated, so the breaker trips automatically on loss of control voltage — useful for safety circuits or emergency-stop chains where a downstream contactor also drops out. Phase failure detection is built into the ETU350M trip unit, so a lost phase on a motor load triggers a trip rather than letting the motor single-phase and overheat. Maximum power dissipation is 101.5 W at rated load. In a sealed enclosure, factor that into the thermal budget — it is not a high-loss breaker for this frame, but at 500 A continuous the heat adds up if you pack multiple breakers in a small panel.
Derating & Ambient Temperature
The 500 A rating holds from 40 °C through 50 °C ambient. Above that, it derates linearly: 495 A at 55 °C, 490 A at 60 °C, 485 A at 65 °C, and 480 A at 70 °C. Operating ambient range is -25 °C to +70 °C, with storage from -40 °C to +80 °C. If your panel ambient runs above 50 °C, the derated current is the number to use for feeder sizing.