The 400 A continuous rating sets the maximum load it can carry without nuisance tripping — size your upstream transformer and bus bars for that figure. The TM-D trip gives you fixed thermal overload protection (L) and fixed magnetic short-circuit protection (I); no adjustment dials, so coordination studies are straightforward: you know the magnetic pickup is fixed at a multiple of In, typically 10–12x for this class. At 690 V AC the Icu drops to 10 kA. Mounts on a backplate or DIN rail — the 185 mm width and 255 mm height mean it needs a full 4-pole slot in the enclosure. The 110 mm depth leaves room for rear-connected bus bars or cable lacing. IP40 front face keeps dust out; IK07 impact rating handles a tool drop during commissioning.
Four-pole (4P) with neutral on the left. Front connections both top and bottom — no need to flip the breaker for reverse feed. Pollution degree 3 (IEC 60664-1) means it is rated for conductive pollution typical in industrial enclosures; no extra conformal coating required in a standard IP40 panel. Overvoltage category III suits fixed-installation distribution boards. Mechanical durability is 15,000 cycles; electrical durability ranges from 12,000 cycles at 440 V at half-rated current down to 3,000 cycles at 690 V at full rated current. If your application cycles the breaker daily under load (e.g., as a disconnect for a welding station), factor the electrical endurance into your maintenance schedule.