The ABB XT3NU3200AFF000XXX is a Tmax XT3N frame breaker — a 225 A, 3-pole thermal-magnetic unit with fixed settings (200–2000 A range) and front flat terminals, mounted directly to a frame rather than a DIN rail.
At 225 A continuous, this breaker handles the main feeder or large motor circuit in a distribution panel. The thermal-magnetic trip gives you inverse-time overload protection plus instantaneous short-circuit response — no electronic trip unit to program, just a fixed curve that's repeatable across identical units. Three poles cover three-phase loads. The frame mount means it bolts into a switchboard or panel chassis, not a DIN rail.