The Schneider Electric LV839141 is a MasterPact MTZ2 circuit breaker — a 1600 A frame, 3-pole drawout unit with H breaking capacity, built to UL 489. Rated 1600 A at 40 °C, it's sized for the main feeder or a big downstream bus on a 480 V or 600 V distribution. The 'H' code means 100 kA Icu at 480 V AC, 85 kA at 600 V AC — that's the fault-clearing muscle that keeps a short from cascading upstream through the switchgear. It ships without a Micrologic trip unit, so you fit the protection curve to your load. The ArcBlok technology contains the arc flash inside the cassette, which matters when you're racking this in and out of a live drawout cradle. Drawout mounting means the breaker cassette slides into a fixed cradle — isolation without unbolting bus bars, which cuts swap time when a trip unit or main contacts need attention. The base plate rails and 4.5 in (115 mm) connection pitch match standard switchgear layouts, so panel builders don't fight the footprint on a retrofit.
Breaking capacity and short-time withstand — the real fault-handling specs
The H breaking capacity code delivers 100 kA Icu at 240 V AC, 100 kA at 480 V AC, and 85 kA at 600 V AC — all per UL 489. The rated short-time withstand current (Icw) is 65 kA for 0.5 s per UL 489, which is the thermal and mechanical stress the breaker takes during a delayed trip coordination — critical for selective coordination downstream. Integral instant protection is set at 81...99 kA, meaning the magnetic trip fires immediately above that window, bypassing the trip unit's delay curve. Breaking time is 25...30 ms, closing response max 70 ms. That's fast enough to limit let-through energy on a bolted fault, but the 30 ms window also means the breaker coordinates with downstream devices that clear in under 3 cycles.
Durability and mechanical life — what the cycle counts mean for maintenance planning
Mechanical durability is 12,500 cycles per ANSI C37.50; electrical durability is 2,800 cycles under rated load. That electrical count is the one that governs replacement interval on a motor feeder or a high-cycle process line — 2,800 load breaks at 1600 A is respectable for a frame this size, but if your application cycles the breaker daily under load, you'll want to track operations on the nameplate counter and plan a contact inspection around 2,000 cycles. Mechanical life is the no-load racking and closing count; 12,500 is typical for a drawout breaker in a main service entrance that sees infrequent switching.
Physical footprint and integration into existing switchgear
Dimensions: 16.8 in deep (426.8 mm), 17.5 in wide (444.3 mm), 17.3 in tall (438.8 mm). That's the cassette envelope — the drawout cradle adds a few inches behind the mounting plate. The 4.5 in (115 mm) connection pitch matches standard bus-bar tap spacing on most North American switchgear lineups. Mounting support is base plate rails, which means the cradle bolts to a flat steel plate; no special adapter brackets needed.