M110 functions with internal bit M7 and timer T12 (55s) to detect the start-up time of belt conveyor; internal bit m29: trigger output bit Y12 (K11) to output and send out early warning bell. Part of the program ladder is shown in Figure 4-2. Trigger timer T0 (10s) → internal bit M0 to eliminate early warning (reset m29); timer T0 logic and internal bit M33 (1 × spoon rod low-level input X5 triggered) trigger internal bit M101 action.