Question Details

Please complete Week-5 Lab Worksheet available in Canvas (Files) and submit in Modules, under week 5 Lab

Do Not Submit This Lab Instructions

Objective

The objective of this lab is to use the PLC simulation software LogixPro to run a traffic light simulation with a cycle of 10 seconds of the green light, followed by three seconds of the yellow light, followed by 10 seconds of the red light. The cycle should continue until the process is stopped.

Software

PLC Simulation Software LogixPro available in Citrix Server Lab

Process: The process starts by pressing a NO push button and can be stopped at any time by pressing a NC push button. The process is a simulation of a street traffic light in which a green light lasts for 10 seconds, followed by a yellow light for three seconds, and finally a red light for 10 seconds. The cycle continues until the process is terminated by pressing the stop push button.

Lab Procedure

STEP 1

Open the LogixPro software in Citrix server.

STEP 2

Click on Simulations on the menu bar at the top. Then, select I/O Simulator. In the ProSim Simulations window on the left, right-click on the I:1/00 switch to change it into a NO start push button. Also, right-click on the I:1/01 switch to change it into a NC stop push button. Then, right-click on the O:2/00 light and select the green color. Similarly, right-click on O:2/01 light to change the color to yellow, and on O:2/02 light to change the color to red, as shown in Figure 1. Note that the actual colors of the lights do not change until they are turned on during the simulation.

Figure 1 - Configuration of Switches and Lights

STEP 3

Enter the ladder logic program, shown in Figure 2, in the ladder logic programming area of LogixPro. The following addressing assignment has been used in this program:

I:1/00 start push button
I:1/01 stop push button
O:2/00 green light
O:2/01 yellow light
O:2/02 red light

Input/output devices may be labeled in LogixPro. Right-click on an instruction, and select Edit Symbol. In the small window that opens, type a nickname, such as Start or Green.

STEP 4

Click on the icon to access the PLC control panel. Select PGM, and click on the Download icon to download the ladder logic program into the PLC.

STEP 5

Press the start push button I:1/00, and verify the operation of the process.

Insert a rung just above the END rung. Place an EIC instruction, and label it with your last name. Copy and paste the ladder logic program into the Lab 5 Worksheet.

STEP 6

Click on the Simulations from the menu at the top of the screen in LogixPro, and select Traffic Simulator. Slightly enlarge the window on the left to see the 3-D traffic light picture. On the ladder logic diagram, left-click on I:1/1 stop to highlight the instruction. Press the Delete key on your computer to delete the instruction. Download the program to virtual PLC, and put the PLC in run mode. Notice that a car is now moving and it will stop any time the light is red. You may notice that after a red light, the yellow light turns on for three seconds before it turns to green. This is unusual, but for the time being, you may ignore it. Reduce the scan time to about 60 to slow down the car movement. Notice that there is a parked car on the left of the screen. Click on Park. Now we have traffic on both sides; however, the lights do not work on the other side. If you wait long enough, you will see some spectacular crashes!

STEP 7

Modify the program for two-way traffic using the addresses given for the lights on the other street. On each side, you may want to consider 10 seconds of green, three seconds of yellow, and 13 seconds of red light. Verify the operation of the two-way traffic light.

STEP 8

Insert a rung just above the END rung. Place an EIC instruction, and label it with your last name. Copy and paste the ladder logic program into the Lab 5 Worksheet.

STEP 9

Lab Report:

Complete Week-5 lab Worksheet available under the Files (Week-5 Lab Folder), then go to Modules, and under Lab assignment submit your lab report.