The ABB XT5HU340BYFF000XXX is a molded case circuit breaker from the XT5H series, rated for the 600 A frame with an LSIG (Long-time, Short-time, Instantaneous, Ground-fault) trip unit, 400 V, 3-pole construction, and UL/CSA certification.
The 600 A frame rating means this MCCB is sized for main feeder or large branch-circuit protection in industrial panels. The LSIG trip unit provides adjustable long-time delay (for overload), short-time delay (for coordination with downstream breakers), instantaneous pickup (for fault clearing), and ground-fault protection — covering the full protection curve for motor loads, transformers, or distribution buswork. UL/CSA listing certifies the breaker for North American panel installations.
The 3-pole configuration handles three-phase loads — typical for a 600 A main breaker in a motor control center (MCC) or a large distribution panel feeding downstream subpanels or heavy machinery.