Download - 2 - PLC Configuration
BEE2961Industrial
Electropneumatic
PLCConfiguration
PLC Introduction--------------------------
A Programmable Logic Controller (PLC) is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or light fixtures
PLCs are used in many industries and machines where it is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact
Programs to control machine operation are typically stored in battery-backed-up or non-volatile memory
A PLC is an example of a hard real-time system since output results must be produced in response to input conditions within a limited time, otherwise unintended operation will result
In this subject, we will use PLC to control electropneumatics system that has been learned previously
What is PLC?
PLC Overview
PC (Siemens STEP 7 Software)
PLC I/O Board
PLC CPU
MPI Interface* Interface adapterbetween PC and PLC
* Processor of PLC
* Input/Output pin for PLC
PLC I/O Board
Analog I/O pin (we don’tuse this in this course)
Digital output pin
Digital input pin
Toggle switch (digital input)
PLC ground
All the hardware components will be connected via PLC I/O board in order to control them according to the ladder programming written
Each hardware components needs to be identified whether they acted as an input or output for/from PLC
All the connected I/O pins must have the same address assigned to them in ladder programming
PLC I/O Board
PLC CPU
Output port indicatorInput port indicator
CPU order number
CPU model/module
Reset switch
Status indicator
Memory slot
The CPU controls all the input and output from PLC I/O Board according to the program that has been downloaded into it
The status indicator shows the status of the CPU whether it is on RUN or STOP mode
The order number must be exactly the same as the order number selected during the hardware configuration to ensure that PC ‘recognize’ the PLC CPU
The input and output port indicator must be monitored regularly to ensure that the programmed system is working according to the ladder programming written
PLC CPU
MPI Interface
FLIPRS232 connecter from PC
Transmission rate selector
Power and active indicator
MPI Interface acts as a connector between PC and PLC CPU
The transmission rate selector must be set to the exact same value set in hardware configuration
Power indicator must be shown in order for PC and PLC CPU to interact with each other
Active indicator will be lighted whenever there’s a download or monitor activity going on in that period of time
MPI Interface
Siemens Step-7 Software is used to write ladder programming that will be transferred to PLC CPU in order to control the electropneumatics system
Before writing a ladder programming, hardware configuration must be set first as the hardware cannot be detected automatically
A misconfigured setting will results in failure or error of the electropneumatics control system
Siemens Step-7 Software
The Flowchart of PLC Configuration Process
Setup a new project
Interface setup
Hardware configuration
Download to PLC CPU
Hardware monitoring test
(optional)
Setting Up a Project--------------------------
1. Start up your PC2. Start up your PLC
◦ PLC doesn’t have a start switch, just switch on after plugging the cable to an electric socket
3. Push the CPU switch to ‘RUN’4. Wait for the status indicator LED
to stop blinking◦ Only DC5V and RUN indicator will
light on
5. Double click SIMATIC Managerin your PC
Starting Procedures
A New Project Wizard will pop-up. Click Next
STEP 7 Wizard
Select CPU: CPU313C MPI address: 2 Click Next
STEP 7 Wizard
Inspect the PLC CPU model
Select Blocks: OB1 Language for Selected Blocks: LAD Click Next
STEP 7 Wizard
OB1 is the main program,we don’t use others in
this subject
LAD for ladderprogramming
Write in a new project name Click Finish
STEP 7 Wizard
Write your projectname here
A new project has been created
SIMATIC Manager Window
Make sure the SIMATIC Managerwindow display your project name
Interface Setup--------------------------
In order to transfer hardware configuration orladderprogramming toPLC CPU, MPIInterface needs tobe setup first Usually, we willuse the defaultsetup, however wewill learn to inspect the setup Click Options Set PG/PC Interface
SIMATIC Manager
Double click PC Adapter [MPI]
SIMATIC Manager
The default setting should be:◦ Address: 3◦ Timeout: 10s◦ Transmission Rate 187.5 Kbps◦ Highest Station Address: 31
Next, click on LocalConnection tab
SIMATIC Manager
Never change this number, it will resultsin hardware error if it is changed
The default setting should be:◦ Connection to: COM1◦ Transmission Rate: 19200
Lastly, click OK
SIMATIC Manager
Ensure that the transmission rateselector on MPI interface is
selected at 19.2
Hardware Configuration
--------------------------
Double click Hardware
SIMATIC Manager
Click ‘+’ to expand the subfolder view
A HW Config will pop-up
HW Config
Rack with individual slot
Configuration settings Hardware catalog
HW ConfigExpand these columns to have a clear view of each settings
If the order number is not the same as the onewritten on your PLC CPU, change it by searchingthe correct order number from Hardware Catalog
HW Config Click Yes
A warning message will pop-upconfirming the changes ofCPU order number
The order number has been changed
HW Config
Make sure the order number is correct
Double click on ‘DI24/DO16’ row
HW Config
Double click here to change the addressfor input (I) and output (Q)
A Properties window will pop-up
HW Config
Click the Addresses tab tochange the input and
output address
The PLC address needs to be started from 0 for input and output. This is due to the I/O port numbering in PLC I/O Board
HW Config
Deselect System Default as wewant to key-in our own address
Change both the starting address to ‘0’ Click OK
HW Config
The end address will beautomatically set
To save the settings, click Save and Compile Then, to download the settings into PLC
CPU, click Download A message willpop-up confirmingthe target module.Click OK
HW Config
Another message will pop-up informing the node address selection. Click OK
HW Config
In order for the new settings to take place, all the previous activity in PLC CPU will be stop during the downloading process
A message will pop-up, click OK
HW Config
After stopping, the module needs to be restarted A message asking for a module restart will be
prompt. Click Yes
Congratulation, the PLC CPU has been downloaded with a hardware configuration settings
HW Config
Hardware Monitoring Tests
--------------------------
After the new settings have been downloaded, all PLC’s activities can now be monitored by STEP-7 Software
To test it, we needto setup the STEP-7Software in an‘online’ mode Click Station Open ONLINE
HW Config
Right click on ‘DI24/DO16’ row Then click Monitor/Modify
HW Config (ONLINE)
Notice that the window nowprompting that it is in ‘online’
mode
A new Monitor/Modify window will pop-up
HW Config (ONLINE)
These are all the input (I) addressthat we have set in
hardware configuration
The input that has been setup isdigital only. As for that, it is
in Boolean format (BOOL)
Check the Monitor checkbox
HW Config (ONLINE)
In Boolean format,‘0’ will be stated as ‘FALSE’
and ‘1’ will be stated as ‘TRUE”
During ‘running’ or ‘online’ activity,notice that the active indicator on
MPI Interface will light on
Now, test the monitoring effects by playing around with the toggle switch on PLC I/O Board
Any toggle switch that isselect to ‘ON’ position willresult in ‘TRUE’ on theMonitor/Modify window After finish, click CLOSE
HW Config (ONLINE)
The resultsmust bethe same