Industrial Ethernet ... from the Office to the Machine - world wide - Band I Ronald Dietrich Industrial Ethernet ... from the Office to the machine - world wide - HARTING The best connections worldwide – because quality connects. HARTING was founded in 1945 by the family that still retains sole ownership of the company. HARTING presently employs more than 2 000 people including 150 highly qualified engineers and over 100 sales engineers who take care of the daily needs of our customers. Today, HARTING is the leading manufacturer of connectors with 34 subsidiary companies in Europe, America and Asia. As the market leader, HARTING offers the advantage of ‘just in time’ services. It is therefore no wonder that the company maintains close business relationships with all of its important customers active in the world market. HARTING is the market leader in several of its product sectors. HARTING can draw on many years of extensive experience gained in achieving high degrees of protection in industrial environments (IP 65 and higher), all of which has flowed into expanding its product portfolio as well as the development of its family of devices for industrial communication. HARTING products are manufactured utilizing cutting edge and efficient productions methods. CAD systems support research and development as well as tool making activities. We abide by our philosophy of quality, which states that only fully automatic manufacturing processes can achieve a zero error rate. In accordance with DIN EN ISO 9001, the organisation and procedures constituting our quality assurance measures are documented in a quality assurance manual. HARTING employs approximately 60 members of staff in quality assurance. The majority of them are highly qualified engineers and technicians who have gained their qualifications through the German Society for Quality (DGQ) or the Swiss Association for Quality (SAQ). Ronald Dietrich Industrial Ethernet ... from the Office to the Machine - world wide - This book was compiled with the technical support of HARTING Electric GmbH & Co. KG, Dezember 2004. All rights reserved by HARTING Electric GmbH & Co. KG, D-32339 Espelkamp. Author: Ronald Dietrich Design and Layout: Ronald Dietrich Translation: Scriptor GmbH, Bielefeld Print and bookbinding: Printshop Meyer, Osnabrück Pictures: Company photos All other illustrations: HARTING Electric GmbH & Co. KG All rights are reserved, especially relating to the translation, reprint and the extraction of illustration, broadcasting, the photo-mechanical or similar repro- duction and storage in data processing systems. This also applies to partial utilization. The reproduction of utility names, trade names, product designations etc. in this documentation does not, even if without special reference, manifest an assumed right to consider names in the sense of legal status for trademarks and trademark protection as being freely available to the public. Important note As a result of research and standardization technical findings are subject to continuous change. The author has exercised meticulous care to ensure that the information and statements in this documentation correspond with the current state-of-the-art. However, the user is not exempt from the obligation to check whether the information in this documentation deviates from the information contained in the original documentation (especially for standards) and to determine the utilization of this information under own responsibility. DIN standards and other technical regulations The DIN standards, VDE regulations and other technical regulations referred to in this documentation relate to the editions available at the time of copy deadline. Relevant for the user of a standard, however, is only the latest edition of the respective standard. DIN standards can be ordered from Beuth-Verlag, Burggrafenstr. 6, 10787 Berlin. Printed on bleached cellulose, 100 % free from chlorine and acid. Preface Dear Reader, this book is intended to introduce you to the subject of Industrial Ethernet. At the same time, it seeks to demonstrate the possibilities open to you to fulfil your requirements for the industrial use of Ethernet by utilizing HARTING components. Following a short summary on the subject of fieldbus technology, we will describe the particular demands placed on Industrial Ethernet and how HARTING provides the appropriate solutions. It is not the intention, nor can this book cover all questions relating to the subjects ‘fieldbus technology’ and ‘Industrial Ethernet’. For more detailed information on these subjects, please refer to the corresponding recommen-dations contained in the ‘Further reading’ list at the end of this book. The standards and guidelines contained in this book were valid in 2004. Dear Reader, if by reading this book you should feel encouraged to take a more in- depth look at the subject of Industrial Ethernet or even put the knowledge gained into practise, you are duty-bound to ensure that you are aware of the latest information concerning prevailing law as well as the latest standards and guidelines. This book is intended to be an introduction to the subject of Industrial Ethernet. It was not written with the intention of providing a detailed description of standards and guidelines. Descriptions of individual devices and components contain no detailed reference to proprietary or patent rights. Further information about HARTING devices and components described in this book are contained in the relevant catalogues and technical manuals. The sources where they can be drawn are contained at the end of this book. Espelkamp, June, 2005 9 Contents Preface .....................................................................................................7 1 General Information about Fieldbus Technology ..........................13 1.1 Historical background .........................................................................13 1.2 The Automation pyramid ....................................................................17 The field level ...............................................................................17 The control or process level ......................................................... 18 The system or cell level ................................................................18 The process control and the management levels ........................ 19 1.3 The Layer model .................................................................................19 Layer 1: Physical Layer ................................................................20 Layer 2: Data Link Layer ..............................................................20 Layer 3: Network Layer ................................................................21 Layer 4: Transport Layer ..............................................................21 Layer 5: Session Layer .................................................................21 Layer 6: Presentation Layer ......................................................... 21 Layer 7: Application Layer ............................................................21 Using the ISO/OSI Reference Model ........................................... 21 1.4 Classifying the fieldbus systems ......................................................... 22 Fieldbus systems with decentralised master transfer ................... 23 Fieldbus systems with central master transfer ............................. 24 1.5 Further information .............................................................................24 2 Industrial Ethernet ............................................................................25 2.1 What is Ethernet? ...............................................................................25 2.2 Classic ‘Shared’ Ethernet ...................................................................26 Ethernet and the ISO/OSI Reference Model ................................ 26 The Ethernet address ...................................................................28 Standard Ethernet Frame .............................................................29 Communication via Shared Ethernet ........................................... 30 Broadcast telegrams ....................................................................31 Network Access Method CSMA/CD ............................................. 33 Different approaches to improving performance .......................... 35 Fast Ethernet ................................................................................35 Gigabit Ethernet ...........................................................................36 10 Gigabit Ethernet ......................................................................38 Ethernet with switching (Switched Ethernet) ................................ 39 2.3 Industrial Ethernet Network ................................................................40 Why Ethernet for industry? ........................................................... 40 Fields of applications for Industrial Ethernet ................................ 43 General requirements placed on Industrial Ethernet networks .... 45 User organisations and protocol variants ..................................... 49 10 3 Transmission Technology and Cabling for Industrial Ethernet ...53 3.1 Network topologies .............................................................................55 Star ...............................................................................................55 Tree ..............................................................................................55