Software for Education and Industry
This tutorial is a series of exercises that will
give you practice programming a PLC in Structured Text using
Codesys. Each exercise is accompanied by a Visualization
(pictorial view of the exercise), and custom Image Pool so you can
"see things move" as a result of the programs you write. The
variables and instructions for each exercise are given so you can
build the Visualization and test the program. Then you are
asked to make various modifications to the control system.
The answer to each modification is provided if you need help.
This tutorial assumes you have completed my tutorial
Structured Text with Codesys or otherwise have a
working knowledge of Codesys and how to launch it, start a new
structured text program, create a Visualization, and run a program
in Simulation mode. It also assumes you know the basics of
how to program:
Learn the purpose of this tutorial, what you need to use it,
how to best use it, what Structured Text is, what Codesys is, and who uses Codesys.
Learn about 2-way, 4-way, momentary and maintained solenoid valves, cylinders, and how to create an ImagePool from custom images for Visualizations. Then program solenoid valves,cylinders,and limit switches to control cylinders.
Use animation to move cars to a spray station via a conveyor, then spray the cars by pressing a pushbutton.
Initially, spraying can occur at any time, whether a car is present or not.
Modify the program so that spraying can occur only when a car is under the sprayer,
the conveyor stops when spraying occurs, and restarts when spraying is done. Also, modify the program so that
spraying occurs automatically for 3 seconds when you press the spray pushbutton and there is an indication that
the sprayer is out of paint after 15 seconds of spraying so the sprayer can be refilled.
4. Conveyor Control
Control a conveyor with three stations along the conveyor where the conveyor can be stopped.
Initially, each stop station consists of a maintained switch. Modify the program by replacing the
maintained switches with momentary switches, and by adding a pushbutton required to reset any stoppage of the conveyor.
This exercise involves a stamping station where a part can be stamped multiple times.
Initially, the part is stamped repeatedly when the Start pushbutton is pressed. Modify the program by adding a counter
so that the part is stamped only X times, and add a thumbwheel switch
so the operator can dial-in the number of times the part is to be stamped.
Use Structured PLC Programming to design control for a pressing operation. When the Start pushbutton is pressed,
a Position cylinder moves a part onto a Raise cylinder which raises the part so that it can be pressed by a Left
and Right cylinder. Modify the control as directed for a more efficient operation.
8. LED Driver
Use a 1 dimensional array to drive a 7-segment LED from a 10 key keypad. Then use a 2 dimensional array to drive the 7-segment LED.
9. Turret Machine
Use Structured PLC Programming to design control for a turret machining operation. When the Start pushbutton is pressed,
cylinders move a part to one of four positions for machining. Modify the control as directed for a more efficient operation.
Use Structured PLC Programming to help design control for a simplified elevator. After seeing how hall buttons can call the
elevator to the correct floor, modify the program to include call buttons in the elevator car. Learn about element layers in
a Visualization, and how to group elements so they move in unison.
11. Traffic Lights
Use Structured PLC Programming to design control for four traffic lights at an intersection. Then modify
the program to include a left turn signal that temporarily stops opposing traffic.
12. Car Wash
Use Structured PLC Programming and a multiplexer to design control for an automated car wash. Then modify the control so that
the Soak cycle includes the Rinse solenoid, and modify it again to provide the option of a Two Soap cycle.