That 400 A rating holds across 40 °C to 50 °C ambient without derating — only starts tapering at 55 °C (384 A) and drops to 360 A at 70 °C, so it handles warm enclosures better than many thermal-magnetic breakers. Breaking capacity hits 330 kA at 240 V, 242 kA at 415 V and 440 V, 187 kA at 500 V, and 52.5 kA at 690 V. The IP40 front protection is standard for enclosed panel mounting; the breaker itself isn't meant for open wet locations. The unit comes with 2 auxiliary switches (HQ type) built in — that's enough for remote status and a separate alarm signal without adding a side-mount module.
The 3VA2440-7HL32-0AC0 measures 248 mm high, 138 mm wide, and 110 mm deep — a standard 3-pole MCCB footprint for the 400 A frame. It mounts with four screws on a backplate or a mounting plate; no DIN rail on this frame size. Make sure your enclosure depth clears the 110 mm plus wiring space for the lugs — 200 mm minimum internal depth is a safe rule of thumb.