The Siemens SENTRON 3VA2450-7MN32-0BL0 is a 3-pole molded case circuit breaker (MCCB) designed specifically for motor protection. It carries a full-load current of 500 A up to 50 °C, then derates slightly to 480 A at 70 °C — so if your panel ambient runs hot, the continuous rating still holds most of its headroom.
Breaking capacity and selectivity
Breaking capacity is the real story here: 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 15.3 kA at 690 V. That 242 kA at 415 V means it can sit upstream of a fault-heavy distribution board without needing a current-limiting fuse ahead of it — the breaker clears a bolted fault at that level on its own. The 15.3 kA at 690 V is still respectable for a 500 A frame; it handles most industrial 690 V bus faults without cascading upstream.
Built-in protection and auxiliary options
Phase failure detection is standard on this unit — it trips if one phase drops out, which prevents single-phasing a motor load. The auxiliary switch complement is 2 auxiliary switches + 1 trip alarm switch + 1 electrical alarm switch HQ, and the breaker ships with an undervoltage release (UVR) fitted. That UVR is the coil that drops the breaker when control voltage is lost, common in emergency-stop chains and safety circuits. The trip indicator gives a visual flag so a technician walking the panel can see which breaker opened without opening the door.
Dimensions and panel fit
Footprint is 138 mm wide by 248 mm tall by 110 mm deep. That 110 mm depth is the dimension that matters for enclosure depth — it fits a 150 mm deep gland plate without the rear cover touching the back wall. The 138 mm width is the standard 3-pole MCCB width for this frame size; it occupies three 45 mm module positions on a DIN rail if the mounting adapter is used, though this breaker is typically bolted directly to a backplate in a motor control center.