The Schneider Electric LV839320 is a Masterpact MTZ3 50 HC automatic switch disconnector rated for 5000 A continuous at 104 °F (40 °C) — that is the current it carries without exceeding its thermal limits in a standard electrical room environment. This is a 3-pole drawout unit built to ANSI C37.50, meaning it is designed for the North American power-distribution standard where the breaker or switch is racked into a cradle, not bolted in place. The drawout chassis and cradle (9.06 in / 230 mm connection pitch) let you isolate the unit for maintenance without unwiring the load — standard practice for switchgear lineups in industrial and commercial buildings. The interrupting ratings tell you where this part fits in a fault-coordination study: 200 kA Icu at 254 V and 508 V AC, and 130 kA Icu at 635 V AC — all with an external relay per ANSI C37.50. Those are the maximum fault currents the device can safely clear. The rated short-time withstand current [Icw] is 100 kA for 1.5 s, also per ANSI C37.50, which means it can carry that fault current for that duration without damage — essential for downstream selectivity where a slower upstream device needs time to clear. In practice, this is a main or large-feeder switch disconnector sized for high-fault-capacity switchboards.
Dimensions: 31.07 in wide, 18.8 in high, 16.8 in deep (789.1 × 478.1 × 426.8 mm). That depth includes the drawout mechanism and ArcBlok arc chamber — verify the switchgear cell depth before specifying. The chassis-mount drawout design means the fixed portion (cradle) stays wired in the cabinet; the moving portion (the switch disconnector itself) racks in and out. The 230 mm connection pitch matches standard ANSI switchgear bus spacing. Control is push-button operated on the front escutcheon, AC network powered.
