The Siemens 3VA2340-6KP32-0CA0 is a SENTRON 3VA2 molded case circuit breaker (MCCB) rated for continuous current of 400 A at 40 °C, designed for line protection in distribution panels. Its interrupting capacity reaches 242 kA at 240 V, dropping to 187 kA at 415 V and 440 V, and 121 kA at 500 V — at 690 V it still clears 7.5 kA. That 242 kA figure at 240 V means it handles high-fault scenarios common in North American 240/120 V center-tapped services without needing a current-limiting upstream fuse.
Thermal derating and ambient limits
The 400 A rating holds flat from 40 °C through 50 °C. At 55 °C it derates to 375 A, at 60 °C to 350 A, at 65 °C to 325 A, and at 70 °C to 300 A — the maximum operating ambient is 70 °C. Storage range spans -40 °C to 80 °C. If the panel ambient runs above 50 °C, the continuous current must be reduced proportionally; the 300 A floor at 70 °C still covers many motor feeder applications.
Built-in undervoltage release
This variant ships with an undervoltage release (UVR) as the auxiliary release — no separate auxiliary switch is fitted. The UVR trips the breaker when the control voltage drops below a threshold, protecting downstream equipment from brownout conditions. The communication function is present, enabling integration with higher-level monitoring systems.
Dimensions and panel fit
The breaker measures 248 mm high, 138 mm wide, and 110 mm deep. The 110 mm depth is the dimension from the mounting surface to the front of the breaker — relevant for gland-plate clearance and enclosure depth. The 138 mm width is the 3-pole footprint; verify the busbar or lug kit spacing matches the existing panel layout if replacing a different MCCB brand.
Power loss and thermal management
Maximum power loss is 98.5 W at rated current. That heat must be dissipated inside the enclosure; factor it into the panel's thermal budget, especially if multiple breakers are ganged in a sealed cabinet.