Trip unit for ComPacT NSX — MicroLogic 4.2 AL
The C1044A100 is a MicroLogic 4.2 AL electronic trip unit from the Schneider Electric ComPacT NSX100...250 range. The protection package is LSoI — long-time, short-time with fixed delay, and instantaneous — with a fixed instantaneous pickup of 1500 A.
What the protection settings mean for your panel
Long-time pickup (Ir) is adjustable from 40 to 100 A in the field, with a fixed time delay. The delay curve gives you 400 s at 1.5 x Ir, 16 s at 6 x Ir, and 11 s at 7.2 x Ir — that's a slow blow for feeder protection, not a motor-start curve. Short-time pickup (Isd) is adjustable 1.5 to 10 x Ir, with a fixed delay. Instantaneous (Ii) is fixed at 1500 A. That means for a 100 A setting, anything above 1500 A trips instantly — no adjustment. Earth-leakage sensitivity (IΔn) and time delay (Δt) are both adjustable via the rotary switch on the front. The neutral protection settings let you choose 0.5 x Ir (3D + N/2), 1 x Ir (4D), or no protection (3D) — match it to your system grounding. IP40 front-of-panel protection handles the usual dry indoor panel.