Principle of Distributed Control System (DCS)

Introduction

Since the first Distributed Control System (DCS) was installed in the late 1970s, the concept of DCS has swept alternative control technologies from the field. The substantial growth, in the construction of plants in the traditional heavy process industries such as power generation, refining, oil and gas, water and petrochemicals, is driving significant growth in the utilization of DCS. The broad architecture of a solution involves either a direct connection to physical equipment such as switches, pumps and valves or connections via a Fieldbus communication system.

With the advent of high-speed data highways and locally collected plant information, DCSs are being used to reduce cabling costs as well as implement advanced control strategies. This course will cover the practical applications of DCS and is based on a selection of subjects that either have had a strong impact on distributed systems today or explore novel ideas that may be of importance for the future. Other topics in the course cover important aspects of distributed systems such as data communications, SCADA, and Safety Instrumented Systems plus PLC applications.

The evolution of computer control systems is discussed in this advanced course and the architecture of contemporary DCS offerings is described in general terms. The course covers hardware, configuration, data communications, user interfaces, and I/O devices. In addition, the course introduces the general maintenance requirements of the DCS. It covers troubleshooting techniques using DCS self-diagnostics and the various diagnostic displays available to engineers and technicians as well as safe and proper component replacement procedures for cards, modules, and power supplies.

The course also looks at the different methods of tuning three-term controllers using the various Zeigler-Nichols approaches.

A section of this course is also concerned with future considerations on the choice and updating of older DCSs, managing the DCS upgrade, choosing between PLC and DCS for the process industries, immediate action items for an aging DCS/PLC and configuration implementation considerations for distributed control systems.

Objectives

Upon the successful completion of this course, you will be able to:

• Apply in-depth knowledge and skills in DCS systems and implement systematic applications, selection and troubleshooting techniques and methods
• Identify the DCS hardware & software, particularly the traditional process controllers, programming, execution time, configuration, etc
• List the parts and configuration of a SCADA system and determine its basic architecture and levels of hierarchy
• Differentiate DCS from PLC and SCADA and discuss their features and functions
• Determine the types of DCS used in petroleum refining processes and explain their specific function in each process
• Employ the concepts of alarm management systems including the types, features, architecture and functions
• Discuss the concepts of humans in control and identify the factors that contribute to their actions
• Recognise the safety issues involved in DCS such as intrinsic safety, explosion, approval standards, etc
• Identify types of redundancy and understand how they work
• Appreciate the principles of analogue and digital field communications and their transmitter classifications, intrinsic safety, Fieldbus communications and technologies, etc
• Discuss the concepts of safety instrumented systems and explain their functions, integration and hazard and risk analysis
• Explain the maintenance considerations of DCS and identify the various types of failures and faults
• Select the proper DCS system for each application and determine the system specification and its functional description
• Update a DCS for optimised operations
• Manage the DCS upgrade
• Choose between PLC and DCS for process industries
• Carry out immediate action items for an ageing DCS/PLC
• Configure implementation considerations for distributed control systems

Training Methodology

This is an interactive course. There will be open question and answer sessions, regular group exercises and activities, videos, case studies, and presentations on best practice. Participants will have the opportunity to share with the facilitator and other participants on what works well and not so well for them, as well as work on issues from their own organizations. The online course is conducted online using MS-Teams/ClickMeeting.

Who Should Attend?

• This course will benefit managers, engineers and other technical staff who are responsible for the selection, application, and implementation and troubleshooting of distributed control systems and their possible upgrades.
• Personnel in technical positions who want to know more about distributed control systems will also benefit from this course.

Course Outline

SAFETY CONSIDERATIONS

• Intrinsic Safety
• Explosion-proof Standard
• Approval Standards
• Oxygen

REDUNDANCY

• How Does It Work?
• Device Redundancy
• Network Redundancy
• Port Redundancy
• System Redundancy
• Power Supply Redundancy
• Cable Reliability

ANALOGUE FIELD COMMUNICATIONS

• Transmitter Classifications
• Intrinsic Safety
• HART and 4 – 2-mA
• Driving the Circuit

SMART MEASUREMENT

• Features
• Brief Specification
• Overview
• Application
• Multi-variable Transmitter

DIGITAL FIELD COMMUNICATIONS

• Data Highway
• Fieldbus Communications
• Advantages of Fieldbus
• Fieldbus Technologies
• HART
• Foundation Fieldbus
• Profibus

SAFETY INSTRUMENTED SYSTEMS

Preview and Concept

• Safety Instrumented Function (SIF)
• Safety Instrumented Systems (SIS)
• Safety Integrity Level (SIL)
• Hazard and Risk Analysis
• Safety PLC
• General Notes

MAINTENANCE CONSIDERATIONS

• Mean Time Between Failures
• Spare Parts
• Types of Failures
• Types of Faults
• Diagnostics

SYSTEM SPECIFICATION

• Functional Description
• Process Diagrams
• P & ID’s
• Loop Diagrams
• HAZOP
• Instrument Index

NEW TRENDS IN WIRELESS TECHNOLOGY

• Application
• Installation
• Network Architecture
• System Integrity
• Wireless in Oil & Gas
• Wireless Transmitters

NEW TRENDS IN DCS

• Updating a DCS for optimized operations
• Managing the DCS upgrade
• Six steps to choose between PLC and DCS for process industries
• Four things to remember about DCS migration
• Six immediate action items for an aging DCS/PLC
• Configuration implementation considerations for distributed control systems