Programmable Logic Controllers, 4th Edition

Cover......Page 2
Title Page......Page 4
Copyright......Page 5
Contents......Page 6
Preface......Page 10
Acknowledgments......Page 13
About the Author......Page 14
Walkthrough.......Page 15
1 Programmable Logic Controllers (PLCs) An Overview......Page 19
1.1 Programmable Logic Controllers......Page 20
1.2 Parts of a PLC......Page 22
1.3 Principles of Operation......Page 26
1.5 PLCs versus Computers......Page 29
1.6 PLC Size and Application......Page 30
Problems......Page 33
2 PLC Hardware Components......Page 35
2.1 The I/O Section......Page 36
2.2 Discrete I/O Modules......Page 40
2.3 Analog I/O Modules......Page 45
2.4 Special I/O Modules......Page 47
Typical Discrete I/O Module Specications......Page 50
2.6 The Central Processing Unit (CPU)......Page 51
2.7 Memory Design......Page 53
2.8 Memory Types......Page 54
2.9 Programming Terminal Devices......Page 55
2.11 Human Machine Interfaces (HMIs)......Page 56
Review Questions.......Page 58
Problems......Page 60
3 Number Systems and Codes......Page 61
3.2 Binary System......Page 62
3.3 Negative Numbers......Page 64
3.4 Octal System......Page 65
3.6 Binary Coded Decimal (BCD) System.......Page 66
3.7 Gray Code......Page 68
3.10 Binary Arithmetic......Page 69
Review Questions.......Page 73
Problems......Page 74
4 Fundamentals of Logic......Page 75
The AND Function......Page 76
The OR Function......Page 77
The NOT Function......Page 78
4.3 Boolean Algebra......Page 79
4.5 Producing the Boolean Equation for a Given Logic Gate Circuit......Page 81
4.6 Hardwired Logic versus Programmed Logic......Page 82
4.7 Programming Word Level Logic Instructions......Page 85
Problems......Page 87
5 Basics of PLC Programming......Page 89
Data Files......Page 90
5.2 Program Scan......Page 94
5.3 PLC Programming Languages......Page 97
5.4 Relay-Type Instructions......Page 99
5.5 Instruction Addressing......Page 102
5.6 Branch Instructions......Page 103
5.7 Internal Relay Instructions......Page 105
5.8 Programming Examine If Closed and Examine If Open Instructions......Page 106
5.9 Entering the Ladder Diagram......Page 107
5.10 Modes of Operation......Page 109
Review Questions......Page 110
Problems......Page 111
6 Developing Fundamental PLC Wiring Diagrams and Ladder Logic Programs......Page 113
6.1 Electromagnetic Control Relays......Page 114
6.2 Contactors......Page 115
6.3 Motor Starters......Page 116
6.4 Manually Operated Switches......Page 117
6.5 Mechanically Operated Switches......Page 118
Proximity Sensor......Page 119
Light Sensors......Page 122
Strain/Weight Sensors......Page 124
Flow Measurement......Page 125
6.7 Output Control Devices......Page 126
6.8 Seal-In Circuits......Page 128
6.9 Latching Relays......Page 129
6.10 Converting Relay Schematics into PLC Ladder Programs......Page 134
6.11 Writing a Ladder Logic Program Directly from a Narrative Description......Page 137
Review Questions......Page 140
Problems......Page 141
7 Programming Timers......Page 143
7.1 Mechanical Timing Relays......Page 144
7.2 Timer Instructions......Page 146
7.3 On-Delay Timer Instruction......Page 147
7.4 Off-Delay Timer Instruction......Page 151
7.5 Retentive Timer......Page 154
7.6 Cascading Timers......Page 158
Problems......Page 162
8 Programming Counters......Page 167
8.1 Counter Instructions......Page 168
8.2 Up-Counter......Page 170
8.3 Down-Counter......Page 177
8.4 Cascading Counters......Page 180
8.5 Incremental Encoder-Counter Applications......Page 183
8.6 Combining Counter and Timer Functions......Page 184
Problems......Page 189
9 Program Control Instructions......Page 194
9.1 Master Control Reset Instruction......Page 195
9.2 Jump Instruction......Page 198
9.3 Subroutine Functions......Page 199
9.4 Immediate Input and Immediate Output Instructions......Page 202
9.5 Forcing External I/O Addresses......Page 205
9.6 Safety Circuitry......Page 208
9.7 Selectable Timed Interrupt......Page 211
9.9 Temporary End Instruction......Page 212
9.10 Suspend Instruction......Page 213
Problems......Page 214
10 Data Manipulation Instructions......Page 218
10.2 Data Transfer Operations......Page 219
10.3 Data Compare Instructions......Page 227
10.4 Data Manipulation Programs......Page 231
10.5 Numerical Data I/O Interfaces......Page 234
10.6 Closed-Loop Control......Page 236
Review Questions......Page 240
Problems......Page 241
11 Math Instructions......Page 244
11.2 Addition Instruction......Page 245
11.3 Subtraction Instruction......Page 247
11.4 Multiplication Instruction......Page 248
11.5 Division Instruction......Page 249
11.6 Other Word-Level Math Instructions......Page 251
11.7 File Arithmetic Operations......Page 253
Review Questions......Page 255
Problems......Page 256
12 Sequencer and Shift Register Instructions......Page 260
12.1 Mechanical Sequencers......Page 261
12.2 Sequencer Instructions......Page 263
12.3 Sequencer Programs......Page 266
12.4 Bit Shift Registers......Page 272
12.5 Word Shift Operations......Page 278
Problems......Page 282
13PLC Installation Practices,Editing, and Troubleshooting......Page 286
13.1 PLC Enclosures......Page 287
13.2 Electrical Noise......Page 289
13.4 Grounding......Page 290
13.5 Voltage Variations and Surges......Page 292
13.6 Program Editing and Commissioning......Page 293
13.7 Programming and Monitoring......Page 294
13.8 Preventive Maintenance......Page 296
Input Malfunctions......Page 297
Ladder Logic Program......Page 299
13.10 PLC Programming Software......Page 304
Problems......Page 306
14 Process Control, Network Systems, and SCADA......Page 309
14.1 Types of Processes......Page 310
14.2 Structure of Control Systems......Page 312
14.3 On/Off Control......Page 314
14.4 PID Control......Page 315
14.5 Motion Control......Page 319
14.6 Data Communications......Page 321
DeviceNet......Page 326
ControlNet......Page 328
Modbus......Page 329
Fieldbus......Page 330
14.7 Supervisory Control and Data Acquisition (SCADA)......Page 331
Review Questions......Page 333
Problems......Page 334
15 ControlLogix Controllers......Page 335
Conguration......Page 336
Project......Page 337
Programs......Page 338
Tags......Page 339
Structures......Page 342
Creating Tags......Page 343
Array......Page 344
Review Questions......Page 346
Program Scan......Page 347
Creating Ladder Logic......Page 348
Tag-Based Addressing......Page 349
Adding Ladder Logic to the \rMain Routine\r......Page 350
Latch and Unlatch Instructions......Page 352
One-Shot Instruction......Page 353
Problems......Page 354
Timer Prede. ned Structure......Page 356
On-Delay Timer (TON)......Page 357
Off-Delay Timer (TOF)......Page 360
Retentive Timer On (RTO)......Page 362
Problems......Page 364
Counters......Page 365
Count-Up (CTU) Counter......Page 366
Count-Down (CTD) Counter......Page 368
Problems......Page 370
Math Instructions......Page 371
Comparison Instructions......Page 373
Move Instructions......Page 375
Problems......Page 378
Function Block Diagram (FBD)......Page 379
FBD Programming......Page 383
Problems......Page 389
Glossary......Page 391
Index......Page 403