The Siemens SENTRON 3VA2440-5MN32-0KL0 is a 3-pole molded case circuit breaker (MCCB) built for motor protection duty. It carries a continuous current rating of 400 A across the full operating temperature range from 40 °C to 70 °C — no derating needed until you hit the upper end of that band. That 400 A holds steady at 40 °C, 45 °C, 50 °C, 55 °C, 60 °C, 65 °C, and 70 °C (through), so if your panel runs hot near a motor starter lineup, this breaker doesn't force a downsized cable or a bumped frame size. Interrupting capacity is what separates this from a standard distribution breaker: 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 9 kA at 690 V (through). At 240 V that's a 187 kA rating — enough for high-fault infrastructure like a large industrial service entrance or a motor control center fed by a big transformer. The 9 kA at 690 V is lower, but that voltage class is rare in motor circuits; the real-world numbers at 415 V and 480 V are where this breaker lives.
What the ratings mean for the panel
Rated insulation voltage Ui is 800 V, so the internal clearances and creepage are sized for 690 V systems with margin. The auxiliary contact block ships as 2 auxiliary switches + 1 trip alarm switch + 1 electrical alarm switch HQ — that's four contacts out of the box, enough to signal a trip back to a PLC or to lock out a starter without adding a separate relay. Phase failure detection is built in, which matters for motor protection: if one phase drops on a running motor, the breaker sees the current imbalance and trips before single-phasing cooks the winding. There's no undervoltage release and no communication module, so this is a straight thermal-magnetic or electronic-trip MCCB — no fieldbus, no remote open/close. Keep that in mind if the spec called for a communicating breaker. Dimensions: 248 mm high, 138 mm wide, 110 mm deep. That 138 mm width is the standard 3-pole MCCB footprint for this SENTRON frame size — it fits the same panel cutout and busbar spacing as other 3VA breakers in the same frame. The 110 mm depth means it clears a 120 mm deep enclosure without the cover bulging.
Lifecycle and sourcing
The supplied basic switch order code is 3VA2440-5MN32-0AA0 — that's the bare breaker without the auxiliary contact block. The -0KL0 suffix on the seed code adds the HQ auxiliary contact set. If you already have a panel with the -0AA0 and need the alarm contacts, you can swap the auxiliary block rather than replace the whole breaker. Maximum power loss is 63.5 W. That's the heat the breaker dumps into the enclosure at full rated current. In a sealed panel with multiple breakers, that heat adds up — factor it into the ventilation or derating calculation if the ambient inside the enclosure climbs toward the 70 °C operating max.