PLC Ladder Diagram
Exercise 1
Design a two-way traffic light signaling system with the following requirements:
1. There should be a START and STOP push button to initiate the signaling process.
2. Once Side-1 is ON, the lights should follow the patterns below:
- Side-1 Green light should be ON for 30 seconds.
- Then Side-1 Amber light should be ON for 3 seconds.
- Then Side-1 Red light should be ON for 30 seconds. The process then repeats.
At the same time, Side-2 lights would be in the following stages:
- Side-2 Red light should be ON for 33 seconds.
- Then Side-2 Green light should be ON for 27 seconds.
- Then Side-2 Amber light should be ON for 3 seconds. The process then repeats.
Side-1
Side-2
Figure 1: Two-Way Traffic Signal