1. INTRODUCTION
Chapter 1

2. Topics Introduction Modern Instrumentation and Control OSI Model
Protocols
Standards

3. Introduction Transfer of Information From One Point to Another
Transmitter/Receiver/Link
Serial Links vs Parallel Links
Digital Data vs Analog
Mutual Agreement

4. Historical Background
Telegraph System
Morse Code
Baudot Code

5. Three Themes
Physical Standards
Open Systems Interconnection
Protocols

6. Standards
EIA-232 Interface Standard
EIA-485 Interface Standard

7. A Typical Serial Data Communications Link

8. Modern Instrumentation
Distributed Control System (DCS)
All Electronic tightly integrated system
Programmable Logic Controller (PLC)
Came from Relay Equipment
SCADA System
RTU’s and Master Station - radio links
Smart Instrumentation
Intelligent Sensors on comms link
Fieldbuses and Devicenets ( and HART)

9. Distributed Control System (DCS)
Based Around a Data Highway
Modular Distributed & Integrated
Each Module Performs Specific Dedicated Task
“Good” on Analog Control
Easy Connection to PLC’s / supervisory Computer Interfaces

10. PLC Programmable Logic Controller Sequence Control and Interlocking
On/Off Inputs/outputs
Ladderlogic Type Programs

11. A Typical PLC System

12. SCADA Supervisory Control and Data Acquisition System
RTU’s to Master Station
Radio Links /Landlines
Also term used for SCADA Software package eg Citect

13. Smart Instrumentation
Microprocessor Based Instrument
Embedded Controllers
Data Communications Capability
RS- 232, RS 485 or Fiber Optic
Ability to Multi-drop With Other Instruments on Same Highway
Wave of the Future...Eg Fieldbus

14. OSI Model Developed by the ISO
Universal Framework for Building A Communications Systems
7 Layer Model
3 Layer Model Very Common for Industry
Missing the 8th Layer

15. Representation of the OSI Model

16. Standards Within A Communications System
Code - Morse - Hex - ASCII
Physical
Protocol - Modbus, Profibus, Hart, Foundation Fieldbus, Ethernet
Open Systems Interconnection Model

17. Protocols Rules for Transmission of Data (Packets) Packet Can Include:
Sync Byte
Destination Address
Source Address
Data
Error Detection
Modbus - Profibus - Canbus - Ethernet - TCP/IP
HDLC - DH+ - HART - DNP3 - Interbus - FTP

18. Basic Structure of an Information Frame Defined
SYNCHRONIZING BYTE Is Used To Synchronize The Receiver.
DESTINATION ADDRESS Is Where The Packet Is Going.
SOURCE ADDRESS Is Where The Packet Has Come From.
DATA Is The Information Contained In The Packet.
ERROR BYTE Is The Result Of The Error Correction Calculation.

19. Voltage Standards EIA/RS-232 Interface Standard
Half / Full Duplex - Point to Point
EIA/RS-485 Interface Standard
Half Duplex - Multidrop

20. RS-232

21. Two Wire Multidrop RS-485

22. Fiber Optic Cable

23. Modbus Protocol Structure

24. Modbus Plus Builds on Modbus Token Passing and deterministic
High Speed - minimum of 1Mbit/s

25. DH+ Protocol Structure

26. HART Protocol 4 - 20 ma Communications

27. ASI Bus Idiot Proof 167kbps and fast for digitals
31 slaves and 124 I/O points with 5ms scan

28. The DeviceNet Model

29. Profibus Typical Architecture of System

30. Foundation Fieldbus Newest Fieldbus H1 standard - 31.25kbit/s
HSE - 100Mbit/s
Three layers plus excellent User Layer

31. Ethernet 10BaseT
MAC = Media Access Control

32. TCP/IP Internet Protocol (IP) Transmission Control Protocol (TCP)
Application Layer
Three Layer Model
Derived from Internet

33. Wireless Communications