400 A MCCB with 187 kA interrupting capacity — motor protection variant
The Siemens SENTRON 3VA2440-5MN32-0BA0 is a 3-pole molded case circuit breaker rated for 400 A continuous current across the full ambient range from 40 °C through 70 °C — no derating needed up to that ceiling. Its interrupting capacity hits 187 kA at 240 V, dropping to 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 9 kA at 690 V, so it handles high-fault utility feeds and large motor branch circuits without cascading upstream. This is the motor protection design variant, meaning the thermal-magnetic trip curve is shaped for motor starting inrush — it holds through the 4 to 17 second short-time delay window before clearing a bolted fault. No auxiliary switch is included on this order code, so if you need remote status feedback, plan for a separate aux contact module.
The 400 A frame uses bolted lug connections; verify busbar spacing and lug kit compatibility against your existing panel layout. Maximum power loss is 66 W, so factor that into enclosure thermal rise calculations — especially in a sealed stainless steel enclosure where natural convection is limited.