GE GFK-0804B Manuel D’Utilisation
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Micro PLC Programmer’s Guide – April 1994
GFK-0804B
Programming Basics
The most important ingredients in creating a successful PLC program are a thorough
understanding of the application itself, and a good measure of common sense.
understanding of the application itself, and a good measure of common sense.
The first step in creating a PLC application program is planning.
h The desired sequence of program actions is determined.
h All of the required inputs and outputs are identified and listed.
h Each input and output is associated with a PLC memory location. For example:
h All of the required inputs and outputs are identified and listed.
h Each input and output is associated with a PLC memory location. For example:
Device
Designation
Memor y Location
Star t switch
Limit switch on conveyor line
Syrup tank #1, level detector
Syrup tank #2, level detector
Conveyor line optical sensor
Input 1
Input 2
Input 3
Input 4
Input 5
Discrete Input Table 1
”
2
”
3
”
4
”
5
Conveyor line motor starter
Operator warning light
Signal to bottle capper
Output 1
Output 2
Output 3
Discrete Output Table1
”
2
”
3
h The program (like the short example program on the facing page) is created with a
programming device and transferred to the PLC.
h Before the system begins full operation, the program is tested and any corrections
that are needed are made.
h The final version of the program is transferred to the PLC, and the application is
ready to go.