Ratings & Fit
The LC1K12105U7: Rated 12 A in AC-3 duty at 440 V — that is the motor-switching current for a 5.5 kW load at 380-415 V or 4 kW at 480-690 V. The 20 A AC-1 rating covers resistive loads. Utilisation categories AC-1, AC-3, and AC-4 are all covered, so it handles both general switching and inching/jogging duty. Three normally-open main poles, one normally-open auxiliary contact built in. Coil is 230-240 V AC, 50/60 Hz. Heat dissipation is 1.3 W — negligible in a crowded panel but worth noting for thermal coordination. Withstands 115 A for 1 second on the power circuit — enough to ride through a short-duration fault without welding contacts. The signalling circuit holds 110 A for 100 ms.