Distributed Control Distributed Control SystemSystemSystemSystem

FundamentalsFundamentals

A distributed control system (DCS) is a control system for a process or plant, wherein control elements are distributed throughout the system.throughout the system.

First industrial control computer system was built 1959

Honeywell and Yokogawa introduced commercial DCS’s in 1975

Hardware Elements of DCSHardware Elements of DCS

Field Devices

Controller

HMI

Historian and Alarm System

Redundancy

DCS ArchitectureDCS Architecture

Courtesy: https://distributedcontrolsystem.wikispaces.com

DCS Interface:DCS Interface:

Main Picture Interface

Faceplate

Alarms Alarms

Process History Trend

DCS InterfaceDCS Interface

Faceplate:Faceplate:

Alarm HistoryAlarm History

Process HistoryProcess History

Merits of DCSMerits of DCS

Single Database

Mitigation of Processor Failure

Easier Redundancy

Operator Training

Limitations OF DCSLimitations OF DCS

Complex failure diagnosis

Cost

Dependant on HMI

Major DCS VendorsMajor DCS Vendors

ABB Ltd.

Emerson Electric Co.

Honeywell International Inc.

Siemens AG Siemens AG General Electric Co.

Any Questions ?Any Questions ?