MicroLogic 6.0 Xi control unit for MasterPacT drawout breakers
The Schneider Electric LV847292WW is a MicroLogic 6.0 Xi electronic control unit for the MasterPacT range of drawout air circuit breakers. It provides LSIG protection — long-time, short-time, instantaneous, and ground-fault — with a trip unit rating selectable from 400 A up to 1600 A. The drawout mounting means the control unit and its breaker can be racked out for maintenance without disturbing line-side connections, a key feature for switchboard installations where uptime matters.
What the LSIG protection scheme means for coordination
LSIG covers the full protection curve: overload (long-time, ANSI 49), short-time delay (ANSI 51), instantaneous (ANSI 50), and earth fault (ANSI 51N). The long-time delay is adjustable in 0.5 s steps, which lets the engineer tune selectivity with downstream breakers. Zone selective interlocking (ZSI) is built in — when multiple MasterPacT breakers are linked, the faulted unit trips instantaneously while upstream units hold, reducing arc-flash energy at the fault point. For a site electrical engineer reviewing a coordination study, this is the feature that makes the difference between a selective and a cascading trip.
Metering and display: what you can read from the front panel
The 128 x 96 pixel LCD shows a full electrical instrumentation suite: per-phase and average currents, neutral and ground-fault current, phase-to-phase and phase-to-neutral voltages, active/reactive/apparent power and energy, power factor, frequency, demand values, and harmonic distortion (THD) for both current and voltage. Measurement accuracy for current is ±0.5 % over the 40–1600 A range for MTZ1 frames. The control unit also logs events, alarms, maintenance data, and min/max instantaneous values with time stamps. This is not just a trip unit — it replaces a separate power meter in the same drawout cassette.
Environmental and installation constraints
Operating altitude goes to 5000 m with voltage derating above 560 V AC. Humidity tolerance is 95 % at 55 °C. The control unit is not approved for wet locations, so keep it in the dry switchgear room. EMC compliance covers electrostatic discharge, radiated fields, fast transients, surge (1.2/50 µs), and conducted RF, with conducted and radiated emissions at Class A per CISPR 22.