30512209-DCSARCHITECTURE-TDC3000

7/27/2019 30512209-DCSARCHITECTURE-TDC3000

1/34

DCS ARCHITECTURE ANDTDC 3000

Presented by:Ziauddin/M. Sohail/Haroon Yousaf


2/34

INTRODUCTION

DCS is the real time component of control

system.Introduced in mid 1970s, it has became anessential component of Process plant controlsystem.

Control system reliability, flexibility and speedare basic functions, offered by DCS.


3/34

FUNCTIONS

DISTRIBUTION

DCS distributes control tasks into relativelysmall sets of independent sub systems.

Distributed tasks includes: Data collection.

Process Control.

Presentation of information

Process analysis

Storage / retrieval of information.


4/34

FUNCTIONS

DISTRIBUTION

Advantages of Distribution:

Lower exposure to component or

subsystem failure.

Better isolation to facilitate maintenance &upgrade.

Flexibility for application development.


5/34


6/34

FUNCTIONS

CONTROL

In addition to control, supportsfollowing:

Information exchange with business,logistics and transportation applications.

Preventive or Predictive maintenancescheduling.

Analysis for better control or troubleshooting.


7/34

FUNCTIONS

SYSTEM

System organizes the command structure &information flow among its constituents part.

This act as a single automation systemunifying the various subsystem.

The subsystem includes:

Process signal input & conditioning.

Process actuator signal output.

Human readable process displays.


8/34

FUNCTIONS

SYSTEM

Human actions i.e. set point changes,manual overrides and alarm handling.

Communications subsystems.


9/34

HIERARCHY OF DCS

Digital control along with networking allowsprocess information to be passed from level

to level within a corporation.This information flow represents the flow ofmeasured variable from a flow transmitter toanywhere in the world.

Such hierarchical representation of theinformation leads to a better understanding.

Broadly, DCS hierarchy consists of 05 levels.


10/34

HIERARCHY OF DCS

Level 0 Field Instruments

This level handles control and processinformation to & from the process field.

Measurement devices provide the informationon the current conditions of process.

The actuators / control valves permit controldecisions to be imposed on the process.

Generally, analog / smart transmitters &control valves dominate this layer / level.


11/34

HIERARCHY OF DCS

Level 1 Process Control

This level operates the process at ornear the targets supplied by others.

High degree of automation control isprovided to achieve operationconsistency.

Reduction in variance in key processvariables and uniform product qualityare obvious benefits.


12/34

HIERARCHY OF DCS

Level 2 Supervisory Control

Set points / Outputs and othercontrollable process variable can be

changed to meet set targets.

Plant optimization & emergencyhandling are the main features at this

level.


13/34

HIERARCHY OF DCS

Level 3 Engineering / Production Control

Configuration of new process values / alarmsor change in control strategy is done at this

level.New graphics displays configuration oramendments for better human interface.

Tuning of Control loops.

Long and short term Production planning ofcontinuous and batch processes.


14/34

HIERARCHY OF DCS

Level 4 Corporate information System

The upper most level of control systemin a corporation.

Long term and strategic functions areperformed from this level.

Inventory control on feedstock andsubsequent contracts.

Production forecast and requirement ofraw materials.


15/34

TDC 3000 An Introduction

TDC (Total Distribution Control) 3000 is thepropriety product from Honey well, USA.

TDC-3000 uses High level control language(CL) for system control and securitystrategies.

Modular structure and its componentscommunicates with each other, withredundancy.

PM (Process Manager) Control hub of thesystem, linked with communication channelsfrom field and Central Control Room.


16/34

TDC 3000 An Introduction

Information travels through high speed co-axial cable.

Data monitoring and control via CRT consolescalled Universal stations.

Specially designed Keyboard to access max.no of input option for process control.

Dedicated component for data storage andretrieval called History Module.


17/34

TDC 3000 An IntroductionHigh level calculations / algorithms arecarried out in AM (application module)

Two communications cables, LCN &UCN for the integrity of the system.


18/34

TDC 3000 Architecture

NIM

U C N

PM

HMAMUS

MCField Signal

Note: All the communication is two way.


19/34

TDC 3000 ArchitectureMARSHELLING CABINET

Signal termination from field to DCS

cabinet and vice versa. Signal conversion and provision of fuses to

protect circuits.


20/34

TDC 3000 ArchitecturePM Cabinet Contains I/O cards and Process Manager modules.

Redundant cards / modules are used for systemreliability.

PM have all necessary algorithms / loop forspecific control strategy.

UCN is the communication link / channel, receivesor transfer data to/from PM modules.


21/34

TDC 3000 ArchitectureLCN Cabinet

It houses NIM, an electronic card, link for

communication b/w LCN / UCN.Application and History modules also reside

in this cabinet.

LCN is the communication channel for highlevel modules i.e. NIM. AM. HM & IOUS.


22/34

TDC 3000 ArchitectureDCS Consoles Universal Stations (US) are man machine

interface, also called IOUS. User friendly graphical displays to control

or view process parameters as a real timecomponent.

Specially designed Keyboard to facilitateaccess of displays, alarms and controller.Touch screen feature for controlling.


23/34

TDC 3000 ComponentsI/O Modules

The analog & digital points (signals)

processing carried out in I/OMs. Input Modules are:

Analog Input high level

Analog Input low level

Digital Input

Pulse Input


24/34

TDC 3000 Components Output Modules are:

Analog out put

Digital out put

Tasks executed in Input Modules, are

Analog to digital conversion

PV characterization

Range checking

Alarm detection

PV source checking


25/34

TDC 3000 Components

Tasks performed by Output modules:

Conversion of OP to 0 to 20 mA.

Selection of direct / reverse controller action.


26/34

TDC 3000 ComponentsProcess Manager

Highly flexible high-performance controller for

control. Configurable according to process requirements.

Capable of executing 160 control loop at a time.

Functions of I/O scanning through regulatory &logic control to more advance control can beimplemented.

The PM consists of Process Manager module & I/Osubsystem


27/34


Process Manager Module consists of:

Communication Processor & Modem

I/O link interface Processor

Control Processor

I/O subsystem consists of:

I/O link (X-Bus)

40 redundant I/O modules


28/34


The processing power of PM is measured in terms

of Processing Units (PU) & Memory Unit (MU) One PM Module guaranteed the max. capacity of

560 PU and 7900 MU.

PU value determined by data type and scan rate.

MU value determined by type of data, max.foranalog signals.

Max. 40 I/O modules can be hooked with PMM.


29/34

TDC 3000 ComponentsUniversal Control Network

Communication channel for PM to high

level modules. It is redundant coaxial cable and can

support up to 32 redundant devices.

Supports peer to peer communication with5 megabit/sec network designed.


30/34

TDC 3000 ComponentsNetwork Interface module (NIM)

It provides link between LCN and UCN.

Its changes protocol of UCN data for LCNand vice versa.

Forwards messages from network to LCN.

Available in redundancy.


31/34

TDC 3000 ComponentsLocal Control Network (LCN)

Data channel / cable for higher level

modules. Token passing protocol with rate of 5

megabits/sec.

Co-axial cable handles 2000 bytes pertoken.

Supports max. 64 nodes.


32/34

TDC 3000 ComponentsHistory Module (HM)

An LCN module, acts a network server for

loading software and data base into LCNmodules.

Historizer for specified point parametersand system events.

Generates trends/reports as perconfiguration.


33/34


34/34

TDC 3000 ComponentsOpen Universal Station (IOUS)

Human interface to process control, highest level

of LCN node. CRT display allows monitoring/control and

handling of alarms.

Displays/prints trends, event history and reports.

Monitor system status and also used as to buildprocess and system database.

Offers multi-window environment.

Documents

30512209-DCSARCHITECTURE-TDC3000