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DISTRIBUTED CONTROL SYSTEM (DCS)
OPERATOR STATION
(A) OPERATOR FUNCTIONS
MONITOR AND CONTROL PROCESS
MANIPULATE PROCESS PARAMETERS, CONTROLLER
MODES
MONITOR AND CHANGE SEQUENCE EXECUTION STATE
PROVIDE VARIOUS PROCESS TRENDS
ALARM MANAGEMENT AND MESSAGE HANDLING
SELECT REPORTS AND HISTORIES FOR VIEWING /
PRINTING
GENERATE PERIODIC LOGS AND JOURNALS
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DISTRIBUTED CONTROL SYSTEM (DCS)
OPERATOR STATION
(B) CURSOR CONTROL DEVICES FOR PLANT OPERATION TOUCH SCREEN
MOUSE
TRACKBALL
QWARTY KEYBOARD
MEMBRANE TYPE INDUSTRIAL KEYBOARD
SINGLE TOUCH CONFIGURABLE KEYBOARD
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DISTRIBUTED CONTROL SYSTEM (DCS)
OPERATOR STATION - DISPLAYS
PROCESS OPERATORS DISPLAYS : CONTINUOUS PROCESS OPERATING DISPLAYS
(GRAPHICS, GROUP, OVERVIEW, DETAIL ETC.)
TREND DISPLAYS, SEQUENCE DISPLAYS
REPORT DISPLAYS
PROCESS ENGINEERS DISPLAYS :
CONFIGURATION DISPLAYS
DATAPOINT BUILDING DISPLAYS
GRAPHIC GENERATION DISPLAYS
SYSTEM COMMANDS AND PROGRAMMING DISPLAYS
LOGS AND REPORT CREATION DISPLAYS
MAINTENANCE ENGINEERS DISPLAYS : SYSTEM STATUS AND PERFORMANCE DISPLAYS
FAULT DESCRIPTION AND MAINTENANCE
RECOMMENDATION DISPLAYS
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DISTRIBUTED CONTROL SYSTEM (DCS)
FEATURES OF OPERATOR DISPLAY
DYNAMIC DISPLAYS
DISPLAY UPDATE RATES
NO. OF COLOURS & RESOLUTION OF THE DISPLAY
NO. OF TAGS SUPPORTED PER DISPLAY
DISPLAY LINKS
GRAPHICS SCROLLING
TRENDING FUNCTION WITH HAIRLINE CURSOR
STANDARD SYMBOLS AVAILABLE FOR GRAPHICS.
TUNING PANEL WITH REAL TIME TRENDINGSINGLE TIER / TWO TIER DISPLAY
NO. OF CRT PER CONSOLE
NO. OF DUAL FUNCTION KEYS FOR SINGLE KEY STROKE ACCESS
MULTI LEVEL ACCESS SECURITY
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DISTRIBUTED CONTROL SYSTEM (DCS)
STANDARD LOGGING FUNCTIONS
ALARM HISTORY / SHIFT
EVENT LOG
HOURLY LOG / HOURLY AVERAGE LOG
SHIFT LOG /SHIFT AVERAGE LOG
DAILY LOG / DAILY AVERAGE LOG
WEEKLY LOG
SHUTDOWN LOG
TRIP INITIATED LOG
SPOT OPERATION LOG
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DISTRIBUTED CONTROL SYSTEM (DCS)
OVERVIEW DISPLAY
NORMALLY 128 TAGS ARE MONITORED
SIMULTANEOUSLY (PAGE)
INPUTS TO BE SHOWN AS VARIABLE LENGTHS ABOVE
OR BELOW THE SET VALUE.
CHANGE OF COLOR IF CROSSES SET VALUE
AUTO MANUAL STATUS TO BE SHOWN ON OVERVIEW
DISPLAY
ALARM CONDITION TO BE SHOWN AS FLASHING
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DISTRIBUTED CONTROL SYSTEM (DCS)
GROUP DISPLAY
NORMALLY 8 TAGS ARE MONITORED SIMULTANEOUSLY
PROCESS VALUE, SET VALUE & CONTROLLER OUTPUT
VALUE TO BE SHOWN AS VARIABLE LENGTHS ABOVE OR
BELOW THE SET VALUE.
ENGG. UNITS, CONTROLLER MODE, LOOP DESCRIPTION,
ALARM CONDITION ETC TO BE DISPLAYED FOR EACH LOOP
TOTAL CONTROL OF THE LOOP DISPLAYED FROM THE
GROUP DISPLAY TO BE MADE AVAILABLE
POSSIBLE TO REPEAT ONE TAG IN MORE THAN ONE GROUP
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DISTRIBUTED CONTROL SYSTEM (DCS)
LOOP DISPLAY
ONE FOR EACH LOOP
DISPLAYS CONTROLLER TUNING CONSTANTS, ZERO & SPAN
VALUES, ALARM SET POINTS, LIMITS ON SET POINT, PV RAW
VALUES, ENGINEERING UNITS, ALARM ENABLE/DISABLEINFORMATION ETC.
ALL THE CHANGES IN ABOVE PARAMETERS IS POSSIBLE, IF
AUTHORISED, FROM LOOP DISPLAY
LOOP DISPLAY ALSO DISPLAYS REAL TIME TREND FOR SET
POINT, PROCESS VARIABLE & OUTPUT WITH SAMPLING
INTERVAL OF 1 SEC FOR NORMALLY 30 MINUTES.
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DISTRIBUTED CONTROL SYSTEM (DCS)
OTHER DISPLAYS
GRAPHIC DISPLAY
TREND DISPLAY
ALARM MONITORING & DISPLAY
ALARM MANAGEMENT - DATE 7 TIME OF OCCURRENCE,
ACKNOWLEDGED/ NOT ACKNOWLEDGED STATUS ETC
ALARM HISTORY
SYSTEM ALARM
MULTI WINDOW DISPLAY
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DISTRIBUTED CONTROL SYSTEM (DCS)DCS OPERATION
CONTROLLER ALGORITHMS
PID
PID WITH RATIO AND BIAS
HIGH/LOW OVERRIDE SELECTOR
AUTO/MANUAL STATION
MULTIPLIER/DIVIDER
SQUARE ROOT EXTRACTOR
SWITCH
CALCULATOR
RAMP/SOAK GENERATOR AX
FC
PC
LCTI
FI
LC
QC
TI
AC
dPC
TC
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DISTRIBUTED CONTROL SYSTEM (DCS)
DCS OPERATION
ALGORITHMS
ARITHMETIC FUNCTIONS LIKE ADDITION, SUBTRACTION,
AVERAGE, SUMMATION ETC.
LINEARISATION BLOCKS LIKE SQUARE ROOT EXTRACTION,
PRESSURE & TEMPERATURE COMPENSATION,
THERMOCOUPLE LINEARISATION, POLYNOMIAL
LIMITER & COMPARATORS
DYNAMIC FUNCTIONS LIKE LEAD-LAG, DEAD TIME, TIMER,
TOTALISER ETC.
LOGICAL FUNCTION BLOCKS LIKE AND, OR, NOT, XOR, FLIP-FLOP ETC.
SEQUENTIAL CONTROL
USER WRITTEN PROGRAMMES IN HIGH LEVEL LANGUAGE.
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DISTRIBUTED CONTROL SYSTEM (DCS)
DCS OPERATION
PERFORM REGULATORY CONTROL
PERFORM DATA ACQUISITION
PERFORM REAL TIME TRENDING OF PROCESS
VARIABLES
PERFORM HISTORICAL TRENDING OF PROCESS
VARIABLES
PRINT SCHEDULED AND EVENT DRIVEN REPORTS
PRINT AND LOG SYSTEM AND PROCESS ALARMS
PERFORM SYSTEM MAINTENANCE FUNCTIONS
Real-time
Information
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DISTRIBUTED CONTROL SYSTEM (DCS)
DCS OPERATION
PROCESS CONTROLLER FUNCTIONS
FUNCTIONAL DESCRIPTION
INPUT / OUTPUT MONITORING
MODULATING CONTROL
LOGIC CONTROL
SEQUENCE CONTROL (THROUGH PROGRAMMING)
Continuous Sequential Logic
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DISTRIBUTED CONTROL SYSTEM (DCS)