That 400 A rating holds flat across the first 10 °C of ambient rise — at 55 °C it still delivers 375 A, and at 70 °C it's good for 300 A. For a panel builder, that means you don't have to oversize the frame for a warm cabinet if you're under 50 °C. The interrupting capacity is 187 kA at 240 V, 121 kA at 415 V and 440 V, 75.6 kA at 500 V, and 17 kA at 690 V — a wide voltage range that covers most low-voltage distribution in one frame.
That third contact is useful for a remote alarm or a PLC input that only fires on a fault, not on a manual open. The undervoltage release (UVR) is built in, so the breaker drops out if control voltage falls below the dropout threshold — standard for applications where you need undervoltage protection on the load.
The breaker measures 184 mm wide, 248 mm tall, and 110 mm deep — a 4-pole frame that fits standard MCCB panel cutouts. The 110 mm depth is the projection from the mounting surface; if you're swapping into an existing panel, check that the enclosure depth clears the rear arc chamber and wiring space. The communication function allows remote monitoring and trip data.