Introduction to PLC programming

The book contains general information about the design, operation and use of PLCs and describes the basic commands and functions used to program them. Clear examples of the use of individual functions are presented using a ladder language. A lot of specific information was also provided for people who want to use drivers in different devices practically. The implementation of an individual programming project - from naming it to sending the control program to the controller - is discussed in detail.

Table of Contents:
Introduction 9
1. The role of PLCs in technology 11
1.1. Contactor relay systems 11
1.2. PLC controller 12
1.3. History of PLC 13
1.4. General properties of PLC 14
1.5. Interfaces for process visualization 16
1.6. SCADA systems as an extension of the capabilities of PLCs 17
1.6.1. Overview of SCADA 18 programs
1.6.2. Communication of SCADA systems with the controller 19
1.7. Application of PLC 19
1.8. Development trends of drivers 21
1.9. Controller division 22
2. Construction of the PLC 24
2.1. Power supply 25
2.2. Central unit 25
2.3. Input module 27
2.3.1. Digital inputs 28
2.3.2. Analog outputs 28
2.4. Output module 30
2.4.1. Digital outputs 30
2.4.2 Analog outputs 32
2.5. Communication module 32
2.6. Special modules 33
3. The principle of PLC 34 operation
3.1. Types of signals 34
3.2. Operating principle of the controller 35
3.2.1. The general operating principle of the controller 35
3.2.2. Detailed operating principle of the controller 37
3.2.3. Application of markers 40
3.2.4. Modes of operation of the PLC 41
4. PLC programming languages 43
4.1. The language of the list of instructions IL 44
4.2. Structured text language ST 44
4.3. The LD 45 Ladder Diagram Language
4.4. The language of FBD block diagrams 46
4.5. The language of the SFC 47 action sequence
5. Codes and number systems used in control systems 49
5.1. Binary system (binary) 50
5.1.1. Converting a binary number to a decimal 50
5.1.2. Converting a decimal to a binary number 51
5.2. Sixtext (hexadecimal) system 54
5.2.1. Conversion of a hexadecimal number to a decimal 54
5.2.2. Converting a decimal to a hexadecimal 55
5.3. Bipod-decimal code (BCD) 56
5.3.1. Conversion of decimal to BCD 56
5.3.2. Conversion of the number written in the BCD code to a decimal number 57
6. Programming of Siemens S7-300 / 400 controllers
6.1. Variable types found in Siemens S7-300 / 400 controllers
6.2. Elementary data types found in Siemens S7-300 / 400 controllers
6.3. Addressing in Siemens S7-300 / 400 controllers
6.4. List of instructions available in ladder language for SIEMENS S7-300 / 400 controllers in the Step 7 64 software
6.4.1. Bit commands (Bit Logic) 65
6.4.2. Counters 75
6.4.3. Time units (Timers) 79
6.4.4. Data transfer (Move) 84
6.4.5. Comparison functions (Comparators) 86
6.4.6. Functions of converting numbers (Converters) formats 92
6.4.7. Operations on words (Word logic) 102
6.4.8. Basic mathematical functions 104
6.4.9. Extended mathematical functions (Advanced Math Functions) 111
6.4.10. Shift and rotation functions (Shift, Rotate) 120
6.4.11. Jump functions 127
7. Programming of VersaMax and VersaMax Micro PLCs by GE Fanuc 130
7.1. Variable types found in GE Fanuc 130 controllers
7.2. Elementary data types found in GE Fanuc 131 VersaMax and VersaMax Micro controllers
7.3. Addressing 133
7.4. List of instructions available in the ladder language in the Proficy package for GE Fanuc 134 VersaMax and VersaMax Micro PLCs
7.4.1. Bit commands (Bit Logic) 134
7.4.2. Counters (Counters) 143
7.4.3. Timers 145
7.4.4. Data transfer (Move Data) 150
7.4.5. Comparison functions (Comparators) 152
7.4.6. Functions of converting numbers (Converters) 160
7.4.7. Operations on words (Word Logic) 168
7.4.8. Basic mathematical functions (175)
7.4.9. Extended Math Functions 184
7.4.10. Shift and rotation functions (Shift, Rotate) 194
7.4.11. Jump function 201
7.4.12. Selected system functions (System Functions) 202
8. Designing a control system using PLC 206 controllers
8.1. Formulation of task 207
8.2. Determination of the result, i.e. the result of the control 208
8.3. Determination of input and output signals 209
8.4. Determining the algorithm of the control process 209
8.5. Development of the allocation table 212
8.6. Development of the proper control program 213
8.7. Analysis of the correctness of the solution 214
8.8. Testing the control program 214
8.9. Planning of device (process) security circuits 215
9. Software configuration for the PLC 217 controller
9.1. Configuration of Siemens S7-300 / 400 controllers in the SIMATIC Step-7 218 software package
9.2. Configuration of GE Fanuc VersaMax Micro PLCs in the Cimplicity Machine Edition / Proficy Machine Edition 231 software package
9.3. Setting of the state memory with backup for the S7-300 / 400 controller 242
9.4. Setting up the latched state memory for the VersaMax and VersaMax Micro 243 controllers
10. Example of a control program for PLC 244
10.1. Formulating the task and determining the result 244
10.2. Determination of input signals 245
10.3. Determining the output signals 245
10.4. The 245 solution algorithm
10.5. Assignment table 248
10.6. Development of the proper control program 249
10.6.1. Example of a control program for Siemens S7-300 / 400 250 controller
10.6.2. An example of a control program for the VersaMax / Versa-MaxMicro 252 controller
10.7. Testing the control program 254
10.8. Planning safety circuits 255
Appendix - Connecting controllers to the programmer, power supply and object 256
Connecting the controller to the programmer 256
Connecting the controller to object 257
Connecting input circuits 257
Connecting output circuits 258
General aspects of connecting the 258 controller circuits