The Schneider Electric C1644A160 is a MicroLogic 4.2 AL electronic trip unit for the ComPacT NSX100...250 molded-case circuit breaker platform. This is the trip unit only — it mounts into the matching NSX breaker frame.
Protection and adjustment
The trip unit provides LSoI protection: long-time overload (L), short-time short-circuit with fixed delay (So), and instantaneous short-circuit (I). The long-time pickup Ir is adjustable from 63 to 160 A. Short-time pickup Isd adjusts from 1.5 to 10 x Ir. Instantaneous pickup Ii is fixed at 2400 A. Long-time delay tr is fixed at 11 s at 7.2 x Ir, 16 s at 6 x Ir, and 400 s at 1.5 x Ir. Short-time delay tsd is also fixed. Integrated earth-leakage protection is Class A, with adjustable sensitivity IΔn and adjustable time delay Δt. The earth-leakage can be disabled via the IΔn rotary switch. Neutral protection is configurable: 0.5 x Ir (3D + N/2), 1 x Ir (4D), or no protection (3D).
Environmental and installation
IP40 protection conforming to IEC 60529. The trip unit is fixed-mount, neutral on the left. Local signalling includes a flashing green LED for ready, red LED at 105 % Ir for overload, orange LED at 90 % Ir for overload, and a yellow indicator for residual current.