CURTIN UNIVERSITY OF TECHNOLOGY DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING OMRON PLC PROGRAMMING

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1 CURTIN UNIVERSITY OF TECHNOLOGY DEPARTMENT OF ELECTRICAL AND COMPUTER ENGINEERING OMRON PLC PROGRAMMING Objectives 1. Familiarize students with programming of Omron CJ1M PLCs 2. Develop skills in writing Ladder programs for industrial applications Equipment OMRON PLC Kit OMRON user manual is provided on the Blackboard Procedure Familiarize yourselves with initial set up, network settings, new program development, compilation, data transfer, etc as shown in the Appendix. Exercise1 the lights in a stairway The lights in a stairway are controlled by three separate switches using a PLC. The Lights can be switched ON and OFF from the ground, 1 st, and 2 nd floors. Write a ladder Program on the OMRON PLC and verify. Exercise 2 Typical Motor Start/Stop Program Write the following program: If is pulsed ON/OFF Then is Latched ON ( stays ON). If =OFF and is pulsed ON/OFF Then = OFF ON-Delay Timers Exercises (read the appendix for detailed instructions) One of the most commonly used programming functions are Timers. Timers have three important parts: the timer number, the timer set point (e.g. 500ms, 4s, 1.3s), and the timer s status bit. The status bit changes from 0 to 1 (OFF to ON) when the time set point is lapsed, and is usually represented by the timer number (e.g. T1). The Status Bit can be used in your program as a switch. Example settings: 1. The Timer Number = (1,2,3,4,) 2. The Time set point = (#10, #40, #50) (Why do we need # in front of the set point?) (How many seconds is #50?) 3. Status Bits = (T1, T2, T3, T4)

2 Example In this example: Timer number = 1, Timer Set Point = 500ms, Status Bit = T1 The program works in the following way: If Input is ON for 500ms or more, then the Output is ON via the timer s status bit T1. Change the set point to 3s, download and observe how the timer works. Exercise: Write a program for an Omron PLC to generate a 1sec ON - 1sec OFF Pulse on Exercise: A process needs to be started as follows: When the input switch is ON then Output keeps flashing 1Sec ON 1Sec OFF to alert the personnel that the machine is about to start If Input stays ON for more than 5sec then turns ON (Machine starts moving) and the flashing-indicator turns OFF At this point can be switched OFF, but output must stay ON The Motor and the Alarm are switched OFF If input is switched ON (Hint: Omron internal register bits are: H0.00--H0.15, H1.00--H1.15 etc ) Exercise: Write a PLC program to control the level of a water tank. If the water is below S2 then pump1 should start. If the tank is full then pump1 should stop. Pump2 runs all the time and stops 10sec after the tank is empty. Input Card Address 2960 Output Card Address 2961 S1, S2, and S3 change state when the water level is AT the position of the sensor or HIGHER. Pump1 Pump2

3 APPENDIX: Omron CX-Programmer: PLC Project Setup 1. Start CX-Program from: Start > PLC-Scada > Omron > CX-Programmer > CX- Programmer 2. Click on Create New Project, and put a name to your project 3. Set the PLC type to CJ1M and Network Type to Ethernet FINS/TCP Click on Settings and select CPU22 Ethernet (Fins /TCPIP) Click Settings > Driver> and enter the IP address of your PLC (Written in the front of your PLC KIT) 4. The programming elements are in the tool bar at the top. 5. To check if you have followed the previous steps correctly: Write the Following program, download the program to the PLC, and test it. If you can not go online, then you have done something wrong on your settings (Go Back to step1) ( )-

4 6. To download the program: first press the go online button as shown in the picture 7. Then press the Transfer Program to PLC button as shown in the picture!!! WARNING!!! NEVER EVER activate (select) IO table 8. IMPORTANT: After the program is downloaded press OK when asked if you want to put the PLC on Run Mode. How to insert On-Delay Timers on your program 1. Click on New PLC Instruction as shown in the picture 2. Click at the end of an empty rung to insert the Instruction (a window will popup). Type TIM 1 #5 to inset Timer T1 with 500ms (or 0.5s) Set Point. Click on OK and OK

5 3. Your program should look like this 4. Add a switch with the input address to activate the timer 5. In the next rung use the Status bit of the Timer (T1) to control the output address Save, download and test your program. To download your program follow steps 6 to 8 from the Omron CX-Programmer: PLC Project Setup. Note: Every time you make changes to your programs you must download them to the PLC. Keep in mind that you may be sharing a PLC with a classmate. Every time your classmate downloads his program, your program is erased from the PLC.