Dcs Training-basic

DISTRIBUTED CONTROL SYSTEM (DCS)

DISTRIBUTED CONTROL SYSTEM Real Time Executive system Basics..

Historical Perspective • 1959: TRW, RW300 computer, refinery control, 72 temperature, 3 pressure, 26 flow sensors • 1962: ICI, Ferranti computer, 129 valves, 224 sensors • 1963: NASA, flight control system • 1968: PDP (DEC), HP 2100, Data\ General Nova (MSI, LSI): interrupt based systems, real-time clock, RTOS • 1970+: VLSI, microcomputers, sensors miniaturization • 1985+: distributed real time systems

computer systems Computer System

Interactive type

Batch type

Input

Programe Processing

Output

Interactive Systems •It takes, process inputs •Processes with prescribed program acts on interventions / interrupts • Issues desired Output . •The programming takes Care of the process behavior and patterns

Interactive systems Interactive system (real-time, reactive, embedded )

Soft real time Statistical Information for supervision only/ Info only.

"Hard real-time" Where the information is processed in definite time frame with intentions to regulate the process.

Soft real-time system Example :. time sharing system of A statististical multiplexor

Terminal

Terminal

Terminal

Multiplexor

Computer

Definition: hard real-time , event driven, embedded, process driven . • real-time : "(A) Pertaining to the actual time during which a physical process transpires. (B) Pertaining to the performance of a computation during the actual time that the related physical process transpires in order that the results of the computation can be used in guiding the physical process" [The IEEE Standard Dictionary of Electrical an Electronic Terms]. • real-time system: Any system in which the time at which the output is produced is significant. This is usually because the inputs corresponds to some movement in the physical world and the output has to relate to that same movement. The lag from input time to outout time must be sufficiently small for acceptable timeliness. [The Oxford Dictionary of Computing]

Watchdog timer • The function of watchdog timeris to ensure that the controller receives the input signals at desired frequency or sampling rate . •

If the signal is not received in defined time frame it issues interrupt command to stop issuing output to process to avoid damage due to loss of communication.

Controller

Interlock / interrupts

Watchdog Timer

Output

processor

•

Some time it de links controller from process ( Trip to manual/ Timed out warning ) and keeps thee system in safe mode or status quo.

Input (t)

Definition RTOS A real-time operating system (RTOS) is an operating system that guarantees a certain capability within a specified time constraint.

Multitasking •It is easy to confuse multitasking with multithreading, a somewhat different idea. •In a computer operating system, multitasking is allowing a user to perform more than one computer task (such as the operation of an application program) at a time. •The operating system is able to keep track of where you are in these tasks and go from one to the other without losing information.

Reference model • Conceptual Realtime system has physical process whichworks in real time manner and it has inputs and outputs sent to RT for computation.

Reference RTS RTS output

RTS input Process

Inputs

Outputs

Function Wise • Open loop • Data acquisition :Collection od Data with Time stampings. • Closed loop

Open loop Open Loopm controls is unidirectional an • It either .. – reads or – Writes back to process

Reference

•

RTS RTS output

RTS input Process

Inputs

Outputs

Data acquisition • Only RTS inputs considered

Reference RTS RTS output

RTS input Process

Inputs

Outputs

Closed loop Closed loop control System has following components

Reference

•Input •Output •Reference or Set Point •Desired Control characteristic or program

RTS RTS output

RTS input Process

Inputs

Outputs

Real Time Events • Time Domain: – Continuous Time related – Random and irregular

• Regular with certain frequency..( Frequency domain)

Type of event patterns •

•

•

periodic pattern: cyclic pattern, with a fixed period

Event

Event period

bounded: next event cannot occur before a given amount of time after a previous event (interarrival time)

Event Interarrival time

bursty: events may occur arbitrarily close toe each other, but there is a bound on the number of events (burst size) that may occur during a specified burst interval

Event Burst interval No. of events = burst size

Events 2 • Irregular: interarrival intervals are not constant but are known before the event occurs • Unbounded: an arbitrary number of events can arrive during any given time window; characterization by a distribution function

t1

t2 t3

t4

Interarrival time

Probability

Distribution function

Interarrival time

RTS- Architecture

• Real time software

Structure of RTS - Hardware Controller • It consists of fillowing functional controllers – Operating softwre – Communication facilities (Bus or Local Area Networking ) – Input / Output subsystem

Structure of RTS software • Operating system • Application tasks

RTS-software application tasks

application tasks

operating system hardware External events physical proces

Role of RTS software • Communication with the environment is defined in terms of external events: Application Tasks must react to these events; • The responsibility of OS: execution of tasks in accordance to external events and prescribed schedule; • Operating System = software (hardware) to facilitate execution of application programs (tasks); • Tasks request services from the OS (make calls to OS). These are internal events. Examples: activate task, stop task perform a communication, etc. • Functions of OS: resource management (processor, memory, peripherals, data);

RTOS • OS-resource management + events handling, • under constraints (predefined time limits);

RTOS activities: uniprocessor system cycle EventHandling; TaskDispatching endcycle; or cycle EventHandling endcycle; or cycle TaskDispatching endcycle; TaskDispatching: Making a task run // denotes interleaved execution of both activities

RTOS activities: uniprocessor system On a uniprocessor system only one task may run a the same time; Scheduling looks at time constraints and decides which task must run; cycle EventHandling; Scheduling; TaskDispatching endcycle; Before a task can be dispatched (assigned to run) the resources i.e. memory must be assigned to it: cycle EventHandling; Scheduling; MemoryManagement; Assign; endcycle;

Summary • Main activities – – – –

Event Handling Scheduling Memory Management Assignment

Scheduling issues • • • •

Ordering of task executions, Assignment of tasks to processors, Security, Protection,

Scheduling is crucial and distinct

Memory management issues • • • • •

Virtual memory Swapping of tasks Sharing of memory (synchronisation, communication) ROM, RAM, Hard disks Buffers, pools, queues

File management issues • Standard file operations • Event handling (device management) issues: – – – – –

Physical process interfacing Interfacing of devices Interfacing of non-standard devices Absence of disk -> debugging, development Host-target approach

Implementation of RTOS • Small executive implements a number of basic OS functions • More complex OS-functions are implemented as special (High / Low priority, memory management) tasks • The interface to OS is formed by System Calls

Application task

RTOS

Application task

System task System task System task

System calls interface

System task

Executive (or kernel)

Hardware

Distributed Operating Systems • Distributed OS control a netwerk of communicating computers; • Tasks running on the different controllers (computers) have a identical / similar view of the system (Single image) • Distributed OS hides the complexity of the distributed hardware to the tasks / programmer

task

task

Controller HW

task

task

Controller HW

communication network

Distributed Operating System

Implementation of Distributed OS • Interceptor: distinguishes between local and global operation • Global executive: coordinate global system calls • Local part: executes local

Application task

Application task

system call interceptor and emulator System task System task System task System task

Global executive task

Local Executive (or kernel)

Computation hardware

Communication hardware

Type of processors •Microcomputers •Programmable logic controllers • Parallel or Multi Processors on a single board / platform ( Client - Sever architecture) •Processing through multiple processors through Networking.

Some examples - Foxboro Foxboro SPEC 200; Philips PCS 8000;

Physical Process

Controller

Displays Operators

S/A Sensors, Actuators

Some examples - TDC 2000, TDC 3000

INDEPENDENT PROCESSING

Comm. 68040

Control 68040

I/O Link

Multi-processor architecture provides guaranteed control performance.

« No I/O capacity

Common Board

tradeoffs

UCN

I/O Link

« No communication

IOP

Intelligent I/O Processors (up to 40)

FTA

Electrical Conditioning and Isolation

«

tradeoffs Point execution in configured intervals

« Intelligent I/O Field Termination Assembly Field Wiring

«

processors Extensive diagnostics

DISTRIBUTED CONTROL SYSTEM (DCS)

For Process plants.

What is DCS ? • DCS is abbreviation for Distributed Control System • As is apparent from the abbreviation, the word ‘Distributed’ supports following functionality’s – Physical Distribution - Nodes or Subsystems can be Distributed i.e located physically apart – Functional Distribution - Specific Functionality is imparted for a Node basing on the combination of hardware and software used. For e.g Application work-processor with Historian, Application work-processor with control configuration software – Structural Distribution - Different Structural hardware platforms (Application Workstation processor, Workstation processor, Control processor etc.) are used to achieve the required functionality.

WHY DCS ? • For Total Plant Automation • For Higher Productivity • For Optimal Process Control • For Advance Process Control

• For Regulatory Compliance • For Management Information System • In Tune With Global Requirement

Information Processing

Enterprise Business

Information

Optimisation Safety

Control System

FIELD

Management Information & application Production report, Inventory report, Specific consumption report, Yield and Accounting reports and Variance reports Quality insurance reports ( LIMS) Env and pollution related Reports Information Management & reporting Historians - Trends, Event recorders Disturbance recorders Optimisation Advance Process Control Hazop/ Risk Management Emergency Shutdown Systems Alarm, Monitoring, Control, Regulator ON-OFF, Interlocks Start-up Permissive Trips FIELD : Single Loop Controllers

Distributed Control System Supervisory Control And Data Acquisition System Programmable Logic Controllers FIELD : Transmitters & field devices Switches , Control valves

The distribution of applications and business logic across multiple processing platforms Distributed processing implies that processing will occur on more than one processor in order for a transaction to be completed. In other words, processing is distributed across two or more machines and the processes are most likely not running at the same time, i.e. each process performs part of an application in a sequence. Often the data used in a distributed processing environment is also distributed across platforms.

Basic Building Blocks • The constitution of DCS can be broadly divided in to three parts – Front End presentation or • MMI - ( Man Machine Interface ) • GUI Graphical User Interface - Operator Graphics

– Control Algorithms and Logic. • Add Subtract, PID, ON-OFF, AND, OR , NAND , etc. – Communication • • • •

Star Ring Linear Bus Star Wired Ring

Basic Building Blocks Platforms

– – – –

Hewlett Packard : ABB IBM AS 400 : Honeywell, Yokogawa Sun Sparc series 30 - 80 : Foxboro Digital (VAX ) Fisher Rosemount

Basic Building Blocks Operating Systems – – – –

HP Unix - ABB Sun Solaris - Foxboro Ultrix/ OS 2 - Honeywell VAX VMS - Fisher Rosemount

Types of databases • Flat file • Hierarchical data bases – Parent Child relation ship

• Relational databases – Oracle – Ingress – Informix – Developer 2000 • Object linked Relational databases

Basic Building Blocks - Control Languages – – – –

Basic Pascal C, C++ Fortran 77

Basic Building Blocks - Control algorithms – – – – – – – – – – – – –

Analog Input / Output Block PID Block / Auto tune PID block Digital Input/Output Block Calculation Block / Advance Calculation Block Characterizer Block Comparison blocks - Less than.More than, Equal to. Switch blocks Data blocks / memory blocks Sequence blocks Mathematical block General Device Block Programmable Logic Block Motor Operator Valve, Pneumatic Valve control block

Communication Network Topologies

Physical

Logical

Linear Bus

Star

Ring

Tree

Star Wired Ring

Ethernet

FDDI

Token Ring

ATM

Communication

Communication 802.3: Established the new standard for a LAN that features a Carrier Sense, Multiple Access with Collision Detection (CSMA/CD). This "new" LAN is properly referred to as CSMA/CD, but is more commonly known as "Ethernet." 802.4: Defined a physical layer standard for a bus topology LAN with a token-passing media access method. This LAN is called Token Bus and can operate at 1, 2, 5, or 10Mbps. 802.5: Established the standards for Token Ring's access methods and physical signaling techniques.

DISTRIBUTED CONTROL SYSTEM (DCS)

Design Basis

DCS Design Basis  The entire design has followed the federal constitution of our country with nominal head and small assisting team like core group at the top.  Network architecture design is such that, it is functionally, geographically and administratively well distributed to have total stability at any point of time.  The DCS design architecture is distributed for:  Different business processes.  Work Breakdown Structure  Maintenance & operation organogram of RPL.

DCS Design Basis  Modular design  Ease of erection, commissioning and distributed operation independent of the Refinery wide LAN.

 Extensive use of Fiber Optic:  Since the entire network is distributed over 50 Sq. Km of area having different earthing resistance for different soils (Rocky to Marine ), Fiber Optic cable external to the building is used

extensively to facilitate distributed and local grounding of equipments to..  Avoid loop currents  Ground currents  Parasitic effect of noises like RFI, EMI and cross talks.

DCS Design Basis  Taking care of limitations of hardware, network and software.  All the six systems are connected through PIN for site wide integration of information.  Real- time data exchange among all the systems using Modbus device integrators.  Minimum communication load on LAN.  Each plant can be started and shutdown independently.

 Expandability of the System at every level .

DCS Design Basis  Ease of Software upgradation at node level without

disturbing complex wide operation.  Control I/Os, respective control processor and respective operator stations are on the same node, thereby minimizing

the traffic on LAN and maximizing the availability of the system for operation.  RTF, RRTF and Marine Terminal systems are kept on the

same LAN for the purpose of ease of data transfer for TIS/OMIS/BOSS applications.  Redundancy at all level - be it processors, communication

or power supplies.

DCS Design Basis  Emergency Shutdown Systems are integrated with DCS and Human Interface from DCS.  All third party packages are integrated with the system

through redundant serial link to achieve a single point operation from DCS i.e 100% measurements parameters are monitored and controlled from single point.

 Remote diagnosis from Foxboro, USA, Holland or Singapore using dial-up networking / ISDN.

DCS Design Basis  Building Block Technology:  The processing is confined within at cell (CP) level so as peer to peer communication between the processors within the node bus

and across nodebus is minimized. This is achieved by means of:  Proper distribution of the tags in the FBMs.  Allocations of loops within CPs.

 Allocation of units at the nodebus level.  Allocation of Operator stations for specific nodebuses.  Provision of hook up for APC application, Optimizer and any third party application software at any stage of time.

DCS Design Basis  Plant Information Network is used for integrating information from Refinery, Aromatics, MTF, CPP, PP and Port Operations.  PIN is implemented using fast Ethernet 10/100 mbps Cisco switches and routers.  PIN is used for following.

 INI51 for connecting two systems.  X-Window for interplant graphics transfer among all six systems.  X-Window anywhere on PCs connected to Reliance WAN.  Integration with third party application like Infoplus.21.  To access historian data from system to Window applications.

DISTRIBUTED CONTROL SYSTEM (DCS)

Large Industrial Systems

DCS MANUFACTURERS

• • • • • • • •

ASEA BROWN BOWERI - ABB TATA HONEYWEL FOXBORO - INVENSYS YOKOGOWA BLUE STAR - YBL ALLEN BRADLEY GE FANUC FISHER ROSEMOUNT TOSHIBA

DCS INSTALLATIONS AT RELIANCE MANUFACTURER ASEA BROWN BOWERI - ABB TATA HONEYWEL FOXBORO - INVENSYS YOKOGAWA BLUE STAR - YBL SIEMENS GE FANUC FISHER PROVOX TOSHIBA

JG

Ö

HZ Ö Ö

SITE PG BARODA Ö Ö Ö Ö

NC

GANDHAR

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Honeywell DCS System Architecture TPS Builder

Uniformance Desktop

Uniformance Applications Server

Remote GUS Display

Fisher Provox DCS System Architecture

Yokogawa Centum DCS System Architecture

ABB DCS System Architecture Information Network TCP/IP

OPERATOR STATION ( OS ) INFORMATION MANAGEMENT SYSTEM (IMS)

ENGINEERING STATION ( ES )

RING 0

DUAL DCN RING

RING 1

C Controller Advant Controller 460 SC Controller

ABB DCS System Architecture Distributed Communication Network (DCN)

     

Total Nodes per Ring 29 Total Nodes/Network 255 Total Rings/Network 85 Maximum end-to-end length/Ring 14 miles/ring Maximum distance between two active nodes 5280 ft* wire Fiber-optic 10,000 ft *recommend 1 mile (5280 ft, 1600 M) between 3 nodes

ABB DCS System Architecture Typical Schematic Diagram For Information Flow From TX

JB

FIELD

JB

TB

B/R

TRIO

CSS

OS

CONTROL ROOM

TB

B/R

TRIO

CSS

To O/P

JB = JUNCTION BOX TB = TERMINATION BOX B/R = BYPASS RELAY

TRIO = TAYLOR REMOTE I/O CSS = CONTROL SUB SYSTEM OS = OPERATOR STATION

FOXBORO I/A Series DCS System Architecture A brief Introduction

I/A Series Fieldbus Digital Field Link Foxboro

Intelligent & Conventional Field Devices

Fieldbus Module

Foxboro

Foxboro

Foxboro

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LBUG

LBUG XXX

Foxboro

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Fieldbus Cards

IEEE 1118

FOXBORO I/A Series DCS System Architecture

I/A Series Nodebus

Workstation Processor (WP - 51)

IEEE 802.3

Control Processor (CP - 40)

Application Processor (AW - 51)

Device Integrator ( DI,MG 30 )

I/A Series Fieldbus IEEE 1118 Digital Field Link Foxboro

Fieldbus Module

Foxboro

Foxboro

Foxboro

Foxboro

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LBUG

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Intelligent & Conventional Field Devices

Communications Processor COM 10

XXX

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Fieldbus Cards

Peripherals; B/W & Color Printers, Terminals; FoxWatch

3rd Party Devices e.g. PLC’s, ESD’s RTU’s Scanners Power Plant Scales Tank Farms Analyzers Spectrum

FOXBORO I/A Series DCS System Architecture

I/A Series LAN I/A Series Nodebus

Workstation Processor (WP - 51)

IEEE 802.3

Control Processor (CP - 40)

Application Processor (AW - 51)

Device Integrator ( DI,MG 30 )

I/A Series Fieldbus IEEE 1118 Digital Field Link Foxboro

Fieldbus Module

Foxboro

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Intelligent & Conventional Field Devices

Communications Processor COM 10

XXX

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Fieldbus Cards

Peripherals; B/W & Color Printers, Terminals; FoxWatch

3rd Party Devices e.g. PLC’s, ESD’s RTU’s Scanners Power Plant Scales Tank Farms Analyzers Spectrum

FOXBORO I/A Series DCS System Architecture Information Network TCP/IP IEEE 802.3 Computers, Workstations, X-Terminals, PC’s etc

I/A Series Nodebus

Workstation Processor (WP - 51)

I/A Series LAN

IEEE 802.3

Control Processor (CP - 40)

Application Processor (AW - 51)

I/A Series Fieldbus IEEE 1118 Digital Field Link Foxboro

Fieldbus Module

Foxboro

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Intelligent & Conventional Field Devices

IEEE 802.4

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Fieldbus Cards

Communications Processor COM 10 RS - 232

Peripherals; B/W & Color Printers, Terminals; FoxWatch

Device Integrator ( DI,MG 30 ) RS - 232

3rd Party Devices e.g. PLC’s, ESD’s RTU’s Scanners Power Plant Scales Tank Farms Analyzers Spectrum

FOXBORO I/A Series DCS System Architecture

Reliance Jamnagar DCS Architecture Functions of Equipment installed in PCC’s System administration and System management (AW51) File server (AW51) Human Interface for Plant Operations (WP51) Alarm management (AW51, WP51) Interface as Engineering station (AW51) Information management - Historian and Reports (AW51) Interface for System Maintenance (AW51, WP51)

Functions of Equipment installed in PIB’s Interface for process inputs and outputs (FBMs and FBCs) Process Control (CP40) Interface for third party systems via serial links (INT30)

DISTRIBUTED CONTROL SYSTEM Jamnagar

DCS SYSTEM RELIANCE JAMNAGAR Highlights:  Total nodes across the complex - 41 No.  LAN Length

-

19.6 Km

 Total panels

-

1102nos.

 Total I/Os

-

182,375 No.

 Total Stations

-

1367 No.

 Total FBMs

-

3307 No.

 Total Serial Links -

270

 Total cost of DCS within complex - 300 crore (approx $60m)plus.

 Fiber Optic cable used - 242 KMs

Reliance Jamnagar DCS Architecture World’s Longest ever Real-Time Control Network for TMS.

World’s Largest System with more then 257 stations in ROS. The DCS is configured as 6 systems as listed below.

 Refinery ( ROS )  Tank farms ( TMS )  Captive Power Plant  Aromatics Plant  Poly Propylene Plant  Port Operations Within each system the I/A series node buses are interconnected by Fiber Optic LAN Interface modules.

Reliance Jamnagar DCS Architecture Refinery

15 Node System Refinery PCC, PIB’s 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 18 Tank Farms 11 Node System Marine PCC and PIB’s 19, 20, 21, 23, 27, 28, 29 Captive Power Plant 3 Node System CPP PCC, and MRS 1, 2 Aromatics Plant 6 Node System ARO PCC, and PIB’s 1, 2, 3, 4, 5 Poly Propylene Plant 5 Node System PPP PCC A&B, and PIB’s 24, 25, 34 Port Operations Single Node System Port PCC

OPTION -1 SPLITTING IN TWO NETWORK - AS PER BUSINESS

R1

R2

R3

R4

R5

R6

R7

F1

F2

F3

F4

U2

13

23

REFINERY OPERATIONS SYSTEM ISSUES: INI51/HOST AW

E1

1. INI51 IS NOT REDUNDANT F5 2. SEPERATE AWS ARE TO BE PROVIDED ON EITHER SIDE 3. MOVED STATIONES ARE TO BE DELETED FROM SY SDEF AND AWS

TCP/IP

4. ADDITIONAL LAN LOADING ON TANK FARM MANAGEMENT SY STEM DUE TO EXAPNSION OF 70 TANKS. INI51/HOST AW

22

19A

U1

19

M1

27

28

29

21

R8

TANK FARM MANAGEMENT SYSTEM

E1

Integration of Applications: Overview IP.21 LIMS

MODEBUS RTU MODEBUS

Plant Information Integration

Open Industrial Standard

ASCII

YIELD ACC. DATA RECONS X-Window AIM*Historian RIMS

AB DH +

INI51

IMAC

Integrated Industry Solutions

TIS

OMIS

BOSS

TAS

APC

Software Overview Operating System: Sun OS 5.5.1 based on Unix IV Human Interface: Foxdraw for Graphics Building & Configuration and Foxview for display of graphics Alarm Manager – For Current Alarm Summary, Alarm History Display. ICC – Integrated Control Configurator, provides software blocks for continuos, sequence and lader logic control. System Configurator – For system configuration of the hardware and software Historian – For collecting sample data for history and trends Report Writer – For daily, weekly, monthly reports SMDH – System Management and monitoring

Functionality Engineering Station (Application Workstation AW51B): Operating system Sun OS runs on AW51B, that is main server for the system and seat on the Nodbus. All other configuration software likes Historian, ICC, and all advance applications also run on AW51B. Mainly used for Configuration, System Diagnostic and downloading configuration to all stations configured. Can be used as Operator station.

Functionality Integrated Control Configuartion: The Integrated Control Configurator database is the backbone of the I/A Series control subsystem and is the primary means by which real-time process variables are translated to the DCS environment The software structure of the Control and I/O (CIO) functions revolve around the "COMPOUND:BLOCK.PARAMETER" concept. A compound as a group of blocks related to a particular Plant Unit, Equipment, Subsystem etc.

A block is a member of a set of predefined algorithms designed to perform mathematical, logical or boolean operations on one or more values. Both blocks and compounds have PARAMETERS. Parameters include realtime values and may be used for display, trending and other processing requirements.

Integrated Control Configuartor

Functionality Human Interface (Operator Work Station): Operator Work station processor with single or dual CRT, Annunciator Key Board, Trackball and touch screen provide human interface. The Concept of efficient process control using an operator interface is with the following basic utilities: Process Graphics ESD Graphics Group / Trend Displays Face Plate Overlays Alarm Manager

Process Graphics

Functionality

Process Graphics: There are four levels of graphics used in Project. Level –1: Complex Overview Level – 2: Plant wide Overview Level –3: Based on PFDs Level – 4: Based on P&Ids In addition to above following are other graphics used for the Project. Group Display: Group of eight Face plate or four Face plate and four treads. Overlay: Faceplates, Pump START/STOP etc.

Functionality

Work Station Access: Environments Workstation Processors provide security through access levels for different categories of system users. Password protection can be configured for each environment. The environments configured for this project are defined in next slide.

Functionality Environment Field_Op_Env

Access Level 1

Authorisation Can view displays, Cannot change values (SP, Output, Auto-Manual etc.), Cannot acknowledge alarms

Ctrl_Rm_Op_Env

2

All Field_Op_Env access, Can change values (SP, Output, Auto-Manual etc.), only for WPs Can acknowledge alarms, Cannot change alarm limits

Supervisor_Env

3

All Ctrl_Rm_Op_Env access, only for WPs Can change alarm limits, Can tune controllers, Cannot access configurators or maintenance functions

Maint_Engr_Env

4

All Supervisor_Env access, Can tune controllers, Can access configurators and make configuration changes, Cannot access software management

Soft_Engr_Env

5

All Maint_Engr_Env access, Can access software management to write programs, Can access Password configurator and change environment menus

Environment

Functionality

ESD Graphics: There are two levels of ESD system graphics: ESD Overview (Level 1) ESD Detail (Level 2) Facilities are provided to move from one level to the other and also sideways within level 2 graphics. The ESD Overview Level graphic lists all ESD's in the area and summarises their statuses. Each plant area has a level 1 ESD graphic. In ESD Detail Level graphics, dynamic Cause and Effect information is depicted. This includes status of the cause and the commanded and actual statuses of the effect (e.g., valve position, pump status etc.).

Functionality FoxAnalyst A separate application for viewing trends is is available in all Operator workstation. Operator can assign a group of 16 trends in one page and save as a scratch pad. This application can be opened from pull down menu in operator environment

Functionality Alarm manager Alarm manager can display alarm information in up to six distinct display windows. Current Alarm Display ( CAD ) Most Recent Alarm Display ( MRA ) Alarm History Display ( AHD ) Alarm Summary New Alarm Display ( NEWALM ) Acknowledged Alarm Display ( ACKED ) Unacknowledged / Return-to-normal Alarm Display ( UNACK)

Alarm manager

Functionality Historian & Reports: The Historian collects, stores, processes, and archives process data from the control system to provide data for trends, Statistical Process Control charts, logs, reports, spreadsheets, and application programs.

The Historian is a tool for collecting, organizing, and storing data for later retrieval. It contains built-in algorithms for reducing data and provides workstation displays to retrieve and display data . Typical data are process analog and/or digital points.

Historian Functions  Collect process control point samples  Reduced point samples  Application-generated alarms & messages

Trends

Functionality Advance Applications: TIS : Tank Inventory System for Tank Farm Management BOSS : Blending & Optimisation Supervisory System

OMIS : Oil Movement & Information System

Information Management: IP.21 is interface with DCS for integration with SAP to form Refinery Information Management System. Foxhistory : Plantwide Consolidated history for generating reports. X-window configuration for remote monitoring.