MasterPact MTZ3 63 H1 — 6300 A Drawout Power Breaker
The LV848335 is a Schneider Electric MasterPact MTZ3 63 H1 drawout circuit breaker, rated 6300 A at 40 °C with H1 performance class delivering 100 kA Ics across the full voltage range from 220/415 V up to 660/690 V AC. Category B selectivity means it coordinates with downstream devices for full discrimination — critical for main incomer or bus-tie positions where a nuisance trip shuts half the plant. Suitability for isolation per EN/IEC 60947-2 lets it serve as the visible-break disconnect for the switchboard section.
Breaking Capacity and Withstand — What the Ratings Mean
The Ics (service breaking capacity) holds at 100 kA from 220/415 V through 660/690 V AC — no derating as voltage rises, which is unusual for an air breaker at this frame size. Icw (short-time withstand) is 100 kA for 3 seconds, giving the downstream protection chain time to clear a fault before the main trips. Icm (making capacity) at 220 kA handles the first asymmetric peak of a bolted fault. For a site electrical engineer coordinating a 480 V switchboard with 65 kA available fault current, this breaker sits well inside its capability with headroom for future utility upgrades.
The breaker with chassis measures 1016 mm wide × 479 mm high × 403 mm deep; without chassis it is 838 mm × 300 mm × 300 mm. Connection pitch is 230 mm. Mounts on rails or base plate — standard for switchboard builders.
Also complies with IEC 61557-12 for power metering. The 12 kV impulse withstand voltage (Uimp) covers surge environments typical of heavy industrial installations.