What the ratings mean for your panel
The Siemens SENTRON 3VA2340-6HL32-0CC0 is a 3-pole molded case circuit breaker (MCCB) rated for 400 A continuous at 40 °C, with a maximum interrupting capacity of 242 kA at 240 V. That interrupting rating means it can safely clear a fault current up to 242 kA without welding contacts or rupturing the case — critical for high-fault locations like transformer secondaries or large motor control centers. The 400 A frame is thermally rated; at elevated ambient temperatures the continuous current derates: 385 A at 55 °C, 370 A at 60 °C, 355 A at 65 °C, and 340 A at 70 °C. For a 400 A feeder, you need to account for the actual panel ambient when sizing — a 55 °C enclosure drops the usable rating by 15 A. The interrupting rating varies by voltage: 187 kA at 415 V and 440 V, 121 kA at 500 V, and 7.5 kA at 690 V. For a 480 V system (common in North America), the 187 kA at 440 V is the closest published figure — still well above typical available fault current in most industrial panels. The breaker is designed for line protection, not feeder or motor protection, meaning its trip curve is optimized for cable and busbar protection rather than motor starting inrush.
Panel integration and mounting
Dimensions are 248 mm high, 138 mm wide, 110 mm deep — a standard 3-pole MCCB footprint for the 400 A frame. Maximum power loss is 98.5 W at rated current — that heat must be evacuated from the enclosure.
Built-in auxiliaries and releases
The breaker ships with two factory-installed HQ auxiliary switches and an undervoltage release (UVR). The HQ designation indicates high-rupturing-capacity microswitches suitable for direct control-circuit switching without interposing relays. The UVR trips the breaker when control voltage drops below a threshold — used for emergency-stop circuits or undervoltage protection on motor feeders. There is no voltage-trip feature, no ground-fault monitoring, and no communication function on this variant; those are available on other 3VA order codes.