MicroLogic 7.3 E Trip Unit for ComPacT NSX — 570 A, LSIR Protection
The Schneider Electric C6347E570 is a MicroLogic 7.3 E electronic trip unit for the ComPacT NSX400...630 range, rated 570 A at 40 °C. It provides LSIR protection — long-time (L), short-time (S), instantaneous (I), and earth-leakage (R) — meeting EN/IEC 60947-2 for distribution applications. The 4-pole unit includes an integrated earth-leakage protection (Class A) and an LCD display for metering and event logs. A 20-minute thermal memory before and after tripping ensures coordination on reclose cycles, critical for keeping a weld line or conveyor string running without nuisance trips.
Protection Functions and Adjustability
Long-time pick-up (Ir) adjusts from 250 to 570 A, with delay tr settable 15–400 s at 1.5×Ir, 0.35–11 s at 7.2×Ir, or 0.5–16 s at 6×Ir. Short-time pick-up (Isd) is adjustable, with delay tsd from 0 to 0.4 s (I²t off) or 0.1 to 0.4 s (I²t on). Instantaneous protection (Ii) is also adjustable. Earth-leakage can be disabled via the IΔn rotary switch. Neutral protection offers four configurations: 3D + N/2, 4D, 3D + OSN, or no protection.
Communication, Metering, and Signalling
The trip unit reports protection and alarm settings, energy metering, demand current and power, power quality, earth-leakage current, time-stamped histories and event tables, instantaneous and demand values, maximeters/minimeters, maintenance indicators, and test reports. Local signalling includes a flashing green LED for ready-to-operate, a red LED at 105% Ir for overload, and an orange LED at 90% Ir for pre-alarm. The LCD display supports on-device interrogation of all these metrics.
Environmental and Installation Ratings
IP40 front-of-panel protection (IEC 60529) keeps out tools and dust. The unit is Class II electrically (double-insulated), fixed-mount, with neutral on the left. No zone selective interlocking (ZSI) is provided.