The LV839317 is a Schneider Electric MasterPact MTZ3 ANSI power circuit breaker rated for a continuous line current of 5000 A at 40 °C (104 °F) — that's the full-load ampacity the main bus sees, not a thermal derate starting point. The breaking capacity code delivers 200 kA Icu at 254 V AC (60 Hz) and 150 kA Icu at 508 V AC (60 Hz) per ANSI C37.50, meaning it can safely interrupt fault currents up to those levels without upstream cascading. The integral instantaneous protection is set at 243...297 kA, so the breaker clears a bolted fault within 9 ms maximum — fast enough to limit arc-flash energy in most distribution switchgear. This is a 3-pole, fixed-mount unit designed for base plate and rail mounting in ANSI switchgear lineups. The 5000 A CT rating matches the breaker's continuous current, so the protection scheme scales directly. The 100 kA Icw for 0.5 s gives coordination engineers headroom for short-time delay settings in selective tripping schemes.
Because the trip unit is not included, the BOM must account for the separate Micrologic order code. This is a common sourcing step for MasterPact breakers — the frame and the trip unit are line items that get paired at assembly. The fixed-mount form factor means it bolts directly into the switchgear bus, not a drawout cassette, so the enclosure cutout and bus connection pitch (9.06 in / 230 mm) need to match the existing lineup.
Deployment context
The ArcBlok technology (included per the description) reduces arc-flash energy during internal faults, which helps lower incident energy levels for maintenance personnel.