The LV846180 is a fixed-mount MasterPact MTZ2 circuit breaker, 4 poles, rated 800 A at 40 °C. The H2V performance class means it interrupts 100 kA at 415 V AC — that's the short-circuit rating that governs selectivity coordination in a main or tie breaker position. Category B selectivity (per IEC 60947-2) means it discriminates with downstream breakers up to its Icu, so a fault on a branch won't take the whole board dark. That's the number a site engineer cares about for arc-flash incident energy and coordination studies. The Icw (100 kA for 1 s) supports selective coordination with upstream devices that need a delayed trip.
Fixed mounting on rails or a base plate. Front or rear connection on both upside and downside — choose based on switchboard layout. Dimensions: 537 mm wide, 352 mm high, 300 mm deep. That depth is the body only — allow additional clearance for rear connections and arc-chamber venting per the mounting instruction. The neutral sits on the left side of the 4-pole assembly.
Standards compliance covers EN/IEC 60947-1, -2, and Annex H for short-circuit coordination, plus IEC 61557-12 for power metering.
Durability and operating conditions
Mechanical durability: 15,000 cycles with periodic preventive maintenance. Electrical durability at rated current: 10,000 cycles at 440 V AC under AC-23A duty (switching motor loads or mixed resistive-inductive), 6,000 cycles under AC-3 (motor starting). Maximum breaking time is 25 ms, closing response time 70 ms — fast enough to limit let-through energy in a fault event. Altitude: no derating up to 2000 m; derate above that per the manufacturer's curve. Power dissipation at rated current is 42 W — factor that into panel thermal calculations, especially in a sealed enclosure.