The Schneider Electric LV839112 is a MasterPact MTZ1 frame circuit breaker — UL 489 listed, 1600 A continuous at 40 °C, three-pole, fixed-mounted, with an H breaking capacity code. It ships without a Micrologic trip unit, so the buyer selects the protection curve separately. This is the bare frame and mechanism, intended for switchboard builders who integrate their own trip package. The interrupting ratings under UL 489 are 65 kA Icu at 240 V AC, 50 kA Icu at 480 V AC, and 50 kA Icu at 600 V AC — these are the fault-clearing limits the breaker guarantees at those voltages. The H code means it sits in the middle of the MTZ1 breaking range, above the standard (S) and below the extreme (L) tier, sized for most commercial and industrial distribution panels where 50–65 kA available fault current is the ceiling.
Durability and coordination data
Mechanical endurance is 10,000 cycles per ANSI C37.50; electrical endurance under load is 1,000 cycles per the same standard. That electrical figure governs maintenance intervals — after roughly 1,000 loaded operations at rated current, the arc chutes and contacts should be inspected. Total break time is 25–30 ms; maximum closing response is 50 ms. The integral instantaneous protection range spans 81–99 kA, meaning the magnetic trip element, if present in the installed trip unit, will operate without intentional delay when fault current exceeds that band.
Fixed-mount design on a base plate with rails. The mounting hole pitch is 70 mm (2.8 in). Overall dimensions: 11.8 in high, 10.9 in wide, 8.2 in deep. That depth includes the mechanism and arc chamber — panel depth must clear the full 209 mm behind the mounting plate. No DIN-rail clip; this bolts into a switchboard or enclosure floor.