Instrumentation Symbols & Standards

8/7/2019 Instrumentation Symbols & Standards

1/15


2/15

Engineeringpapers.blogspot.comFIC : FLOW INDICATING CONTROLLER

FS : FLOW SWITCH

FY : FLOW CONVERTER

FA : FLOW ALARM

FR : FLOW RECORDER

FRC : FLOW RECORDING CONTROLLER

LEVEL

L : LEVEL

LI : LEVEL INDICATORLG : LEVEL GAUGE

LIT : LEVEL INDICATING TRANSMITTER

LCV : LEVEL CONTROL VALVE

LDT : LEVEL DISPLACER TRANSMITTER

LIC : LEVEL INDICATING CONTROLLER

LRC : LEVEL RECORDING CONTROLLER

LS : LEVEL SWITCH

LSH : LEVEL SWITCH HIGH

LSL: LEVEL SWITCH LOW

LA : LEVEL ALARM

RLT : RADAR LEVEL TRANSMITTER

GENERAL

DCS : DISTRIBUTED CONTROL SYSTEM

SCADA: SUPERVISORY CONTROL AND DATA ACQUISITION SYSTEM

PLC : PROGRAMMABLE LOGIC CONTROLLER

HART : HIGHWAY ADDRESSABLE REMOTE TRANSDUCER

HHT : HAND HELD TERMINAL

SFC : SMART FIELD CONFIGURATOR

ESD : EMERGENCY SHUT DOWN

AOV : AIR OPERATED VALVEMOV : MOTOR OPERATED VALVE

SV : SOLENOID VALVE

XVE : VIBRATION PROXIMITOR

XVT : VIBRATION TRANSMITTER

AE : ANALYZER

JB : JUNCTION BOX

ILD : INSTRUMENT LOOP DIAGRAM

P&ID : PIPING AND INSTRUMENT DIAGRAM

IIS : INSTRUMENT INSTALLATION SCHEDULE

TDR : TIME DELAY RELAY

SP : SET POINT

NC : NORMALLY CLOSED

NO : NORMALLY OPEN

MCC : MOTOR CONTROL CENTRE

IAS : INSTRUMENT AIR SUPPLY

IGS : INSTRUMENT GAS SUPPLY

ACFO : AIR TO CLOSE FAIL OPEN

AOFC : AIR TO OPEN FAIL CLOSE

FFA : FLAME FAILURE ALARM

P/I P to I : PNEUMATIC TO CURRENT CONVERTER

I/P I to P : CURRENT TO PNEUMATIC CONVERTERPB : PUSH BUTTON

Page 2 of 15


3/15

Engineeringpapers.blogspot.comPID : PROPORTIONAL, INTEGRAL AND DERIVATIVE

E/H: ELECTRO HYDRAULIC ACTUATOR

BOV : BLOW DOWN VALVE

A/M : AUTO / MANUAL 2 POSITION SWITCH

ZS : POSITION SWITCH

HS : HAND SWITCH

Page 3 of 15


4/15

Engineeringpapers.blogspot.com

2) INSTRUMENT LINE SYMBOLS

2.1) INSTRUMENT SUPPLY or CONNECTION TO PROCESS ___________________

2.2) PNEUMATIC SIGNAL ___________________

2.3) ELECTRICAL SIGNAL (ANALOG SIGNAL) (mA DC (OR) VDC) ------------------------

3.4) ELECTROMAGNETIC or SONIC SIGNAL ___________________

3.5) HYDRAULIC SIGNAL ___________________

2.6) CAPILLARY TUBE(FILLED SYSTEM) ___________________

2.7) PULSE TRAIN _ _ _ _ _ _ _

2.8) INTERNAL SYSTEM LINK(SOFTWARE or DATA LINK)

-----------------------------------------------------------------------------------------------------------------

3) TYPES OF SUPPLY

3.1) AS - AIR SUPPLY IA INSTRUMENT AIRPA PLANT AIR

3.2) ES ELECTRICAL SUPPLY

3.3) GS GAS SUPPLY

3.4) HS HYDRAULIC SUPPLY

3.5) NS NITROGEN SUPPLY

3.6) SS STEAM SUPPLY

3.7) WS WATER SUPPLY

The ES or AS symbol is to be used only for Field Devices requiring supply. Forpanel mounted instruments power supplies are not shown on flow sheet.

Page 4 of 15

Options

IAS 130 kPa

ES 24 V DC


5/15


4) GENERAL INSTRUMENT SYMBOLS

Page 5 of 15


6/15


Page 6 of 15


7/15


5) IDENTIFICATION LETTERS

TABLE 1

FIRST LETTER (4) SUCCEEDING LETTER (3)

MEASURED / INITIATINGVARIABLE

MODIFIER READOUT /PASSIVE

FUNCTION

OUTPUTFUNCTION

MODIFIER

A ANALYSIS (5, 19) ALARM

B BURNER, COMBUSTION USERS CHOICE (1) USERS CHOICE (1) USERS CHOICE (1)

C USERS CHOICE (1) CONTROL (13)

D USERS CHOICE (1) DIFFERENTIAL(4)

E VOLTAGE SENSOR (PRIMARYELEMENT)

F FLOW RATE RATIO(FRACTION) (4)

G USERS CHOICE (1) GLASS, VIEWINGDEVICE (9)

H HAND HIGH (7,15,16)

I CURRENT (ELECTRICAL) INDICATE (10)

J POWER SCAN (7)

K TIME, TIME SCHEDULE TIME, RATE OFCHANGE (4, 21)

CONTROL STATION(22)

L LEVEL LIGHT (11) LOW (7, 15, 16)

M USERS CHOICE (1) MOMENTARY(4)

MIDDLE,INTERMEDIATE (7,

15)

N USERS CHOICE (1) USERS CHOICE (1) USERS CHOICE (1) USERS CHOICE (1)

O USERS CHOICE (1) ORIFICE,RESTRICTION

P PRESSURE, VACUUM POINT (TEST)CONNECTION

Q QUANTITY INTEGRATE,TOTALIZE (4)

R RADIATION RECORD (17)

S SPEED, FREQUENCY SAFETY (8) SWITCH (13)

T TEMPERATURE TRANSMIT (18)

U MULTIVARIABLE (6) MULTIFUNCTION (12) MULTIFUNCTION (12) MULTIFUNCTION (12)

V VIBRATION, MECHANICALANALYSIS (19)

VALVE, DAMPER,LOUVER (13)

W WEIGHT, FORCE WELL

X UNCLASSIFIED (2) X AXIS UNCLASSIFIED (2) UNCLASSIFIED (2) UNCLASSIFIED (2)

Y EVENT, STATE / PRESENCE(20)

Y AXIS RELAY, COMPUTE,CONVERT(13,14,18)

Z POSITION, DIMENSION Z AXIS DRIVER,ACTUATOR,

UNCLASSIFIEDFINAL CONTROLELEMENT

NOTE: Numbers in parentheses refer to specific explanatory notes.

Page 7 of 15


8/15


6) TYPICAL LETTER COMBINATIONSTABLE 2

Page 8 of 15


9/15


7) FUNCTIONAL BLOCKS FUNCTIONAL DESIGNATIONS

THE FUNCTION DESIGNATIONS ASSOCIATED WITH CONTROLLERS, COMPUTING DEVICES, CONVERTERSAND RELAYS MAY BE USED INDIVIDUALLY OR IN COMBINATION (ALSO SEE TABLE 1, NOTE 14). THE USE OFA BOX AVOIDS CONFUSION BY SETTING OFF THE SYMBOL FROM OTHER MARKINGS ON A DIAGRAM ANDPERMITS THE FUNCTION TO BE USED AS A STAND ALONE BLOCK ON CONCEPTUAL DESIGNS.

TABLE -3

Page 9 of 15


10/15


Page 10 of 15


11/15


Page 11 of 15


12/15


Page 12 of 15


13/15


Page 13 of 15


14/15


Page 14 of 15


15/15


8. APPLICATION EXERCISE

Documents

Instrumentation Symbols & Standards