The ABB XT5HU330ABFF000XXX is a molded case circuit breaker from the XT5H series, 400 A frame size, with a TMA electronic trip unit adjustable from 300 A to 3000 A. Three-pole, fixed thermal-magnetic plus electronic (TMA) protection, FF terminal configuration, UL-listed.
The 400 A frame is the physical housing size; the TMA trip unit's adjustable range (300–3000 A) lets you set the continuous current rating to match the downstream load — typically a transformer, large motor, or feeder circuit. The FF terminal type (front-flange) is designed for panel mounting with busbar connections, common in switchgear and MCC lineups. UL listing means the breaker meets UL 489 requirements for use as a branch-circuit protective device in North American panels; you can rely on it for SCCR coordination without additional derating.
Deployment context
Mounts in a standard switchgear or panelboard — the FF terminals accept busbar or cable lugs up to the frame rating. The TMA trip provides adjustable long-time, short-time, and instantaneous protection, so it suits motor feeders, transformer primaries, or main disconnects where coordination with downstream breakers is needed. No special cooling clearance beyond the manufacturer's standard side-to-side spacing is required.