What it is and what it does
The Siemens 3VA2440-5MN32-0CC0 is a SENTRON molded case circuit breaker (MCCB) designed specifically for motor protection. It carries a continuous current rating of 400 A across the full ambient temperature range from 40 °C to 70 °C, meaning no derating is needed as the panel warms up — a practical advantage in a crowded enclosure. The interrupting capacity tells you where this breaker can safely clear a fault: 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. That 187 kA figure at 240 V is high — it handles a bolted fault near a large transformer without needing a current-limiting fuse upstream.
Protection and auxiliary features
Built-in phase failure detection and an undervoltage release (UVR) as the auxiliary release make this a complete motor-protection package. The UVR drops the breaker if supply voltage falls below a set threshold, which protects the motor from single-phasing or brownout conditions. Two auxiliary switches (HQ type) are included for status feedback to a PLC or annunciator panel. The trip indicator is not fitted on this variant, so you won't get a local mechanical flag showing a trip event — plan on reading the auxiliary switch state or using a remote indication circuit. No communication function is built in, so this is a standalone breaker, not a metering or networked unit.
Physical fit and environment
Dimensions are 248 mm high, 138 mm wide, and 110 mm deep. That 110 mm depth is the body only — factor in handle throw and wiring space when laying out the panel. The operating temperature range is -25 °C to 70 °C, so it's fine for unheated electrical rooms or outdoor enclosures in moderate climates. Storage range extends from -40 °C to 80 °C. Maximum power loss is 66 W. That's the heat it dumps into the enclosure at full rated current — account for it in the thermal design of the panel, especially if other heat sources are nearby.