可编程逻辑控制

kong2008

Technological advances in recent years have resulted in the development
of the programmable logic controller and a consequential revolution of
control engineering. This book is an introduction to programmable logic
controllers and aims to ease the tasks of practising engineers coming first
into contact with programmable logic controllers, and also provides a
basic course for students on courses such as Nationals and Higher
Nationals in Engineering, company training programmes and as an
introduction for first year undergraduate courses in engineering.
The book has been designed to provide full syllabus coverage of the
BTEC National and Higher National in Engineering units Programmable
Controllers and Programmable Logic Controllers from Edexcel. It
addresses the problem of different programmable control manufacturers
using different nomenclature and program forms by describing the
principles involved and illustrating them with examples from a range of
manufacturers. The text includes:
w The basic architecture of PLCs and the characteristics of commonly
used input and outputs to such systems.
w A discussion of the number systems: denary, binary, octal,
hexadecimal and BCD.
w A painstaking methodical introduction, with lots of illustrations, of
how to program PLCs, whatever the manufacturer, and make use of
internal relays, timers, counters, shift registers, sequencers and data
handling facilities.
w Consideration of the standards given by IEC 1131-3 and the
programming methods of ladder, functional block diagram,
instruction list, structured text and sequential function chart.
w To assist the reader to develop the skills necessary to write programs
for programmable logic controllers, many worked examples,
multi-choice questions and problems are included in the book with
answers to all multi-choice questions and problems given at the end
of the book.
Changes from third edition
The fourth edition is a complete restructuring and updating of the third
edition and includes a more detailed consideration of IEC 1131-3,
including all the programming methods given in the standard, and the
problems of safety. This includes a discussion of emergency stop relays
and safety PLCs.