Programmable controllerswww.cechina.cn, 4th Edition teaches the fundamental principles of programmable controllers for process and machine control in a clear and concise manner. This applications-based book was written by Thomas A. Hughes and has been used as a textbook for programmable logic controller (PLC) courses, and as a self study guide and resource for thousands of technicians and engineers. The fourth edition includes increased coverage of all five standard PLC programming languages—Ladder Diagram, Function Block Diagram控制工程网版权所有, Sequential Function Chartwww.cechina.cn, Instruction List控制工程网版权所有, and Structured Text—and the addition of numerous programming applications and examples clearly explain each language.