Instrumentation Note

1. WHAT IS
INSTRUMENTATION ??
DHAVAL PANCHAL
panchaldhaval7@yahoo.com

2. What is Instrumentation ?
♦ An Instrumentation is the art of measuring the value of
some parameters like, Pressure, Flow, Level or
Temperature and supplying a signal that is proportional to
the measured parameter.
♦ It makes available the necessary process information like
indication, trending, status.
♦ It also controls the parameter within a specified limits at
specified value.
♦ It also helps to monitor Health and performance of
Equipments.

3. Parameters Measured for process control
♦ Pressure
♦ Level
♦ Flow
♦ Temperature
♦ Quality of intermediate and finished
products
♦ Speed, vibration, displacements for rotary
machines

4. Types of parameter interface
♦ Local Indication
e.g - PG, TG, Rotameters
♦ Remote indication
e.g – Indication on DCS, annunciation
♦ Recording or Trending
Chart/chartless recorders, DCS trending

5. Types of signal transmission
♦ Pneumatic - 0.2 to 1.0 kg/cm2 air pressure thro’ Cu, SS,
tubes.
♦ Electrical - 4 to 20 mA through copper conductor cables
♦ Digital signals through twisted / shielded pair cable
♦ Optic Fiber cables
♦ Wireless transmission through radio frequency

6. Process parameter
measuring techniques

7. Pressure measurement
♦ Pressure is the actual measurement of force
acting on area of surface.
♦ P= F/A
♦ The Unit of measurement of pressure is PSI
(pound per square inch) or KG/Cm2.

8. Common Pressure Detectors are
♦ Bourdon Tube
♦ Bellows
♦ Diaphragms
♦ Capsules
♦ Gauge pressure Transmitters

9. Flow Measurement
♦ Various types of methods are used for flow
measurement. Commonly used method is DP cell
type Flow detector.
♦ Orifice plate
♦ Venturi Tube
♦ Annubar
♦ Vortex flow meter
♦ Thermal mass flow meters
♦ Micromotion Mass flow meters

10. Thermal Mass flow meter
♦ The rate of heat absorbed by a flow stream is
directly proportional to its mass flow. As
molecules of a moving gas come into contact
with a heat source, they absorb heat and
thereby cool the source. At increased flow
rates, more molecules come into contact with
the heat source, absorbing even more heat.
The amount of heat dissipated from the heat
source in this manner is proportional to the
number of molecules of a particular gas (its
mass),

11. Micromotion mass flow meter
♦ This meter uses the Coriolis effect to
measure the amount of mass moving
through the element. The substance to
be measured runs through a U-shaped
tube that is caused to vibrate in a
perpendicular direction to the flow. Fluid
forces running through the tube interact
with the vibration, causing it to twist.
The greater the angle of the twist, the
greater the flow

12. Coriolis Flow Measurement
Principal
Outlet
C1
Inlet
C2
Time
∆T∆T
Outlet
C1
Inlet
C2
Time
m = km x ∆t

13. Doppler Flow Meter
♦ Acoustic signals of known frequency
are transmitted, reflected from particles,
and are picked up by a receiver. The
received signals are analyzed for
frequency shifts and the resulting mean
value of the frequency shifts can be
directly related to the mean velocity of
the particles moving with the fluid.

14. Doppler flow meter how it works

15. Level Measurement
♦ Differential Pressure type
♦ Capacitance
♦ Nucleonic
♦ Ultrasonic
♦ Radar
♦ Vibrating – tuning fork type
♦ Paddle type

16. Differential Pressure type

17. Capacitance

18. Nucleonic

19. Strip source Cells
Detector
Sources
Amplifier
Different types of Nucleonic Level Measurement

20. Ultrasonic

21. Vibrating – tuning fork type

22. Paddle type

23. Level Measurement Accuracy
♦ DP TYPE:0.1 TO 0.5 % OF SPAN
♦ CAPACITANCE TYPE: 2% OF FS
♦ NUCLEONIC: 1 % OF SPAN
♦ ULTRASONIC: 2 % OF FS
♦ RADAR TYPE:0.5 % OF FS

24. Temperature Measurement
♦ RTD
♦ Thermocouple
♦ Bimetal type
♦ Infrared type

25. Thermocouple
♦ A thermocouple is a sensor for measuring
temperature. It consists of two dissimilar
metals, joined together at one end. When
the junction of the two metals is heated or
cooled a voltage is produced that can be
correlated back to the temperature

26. RTD
♦ Resistive temperature devices capitalize on
the fact that the electrical resistance of a
material changes as its temperature changes
♦ RTDs rely on resistance change in a metal,
with the resistance rising more or less
linearly with temperature.

27. Bimetal Type (TGs)
♦ Bimetallic devices take advantage of the
difference in rate of thermal expansion
between different metals. Strips of two
metals are bonded together. When heated,
one side will expand more than the other,
and the resulting bending is translated into a
temperature reading by mechanical linkage
to a pointer.

28. Infrared Type
♦ Infrared sensors are non contacting devices.
They infer temperature by measuring the
thermal radiation emitted by a material
♦ Temp. range is –50 to 1000 degc. With
accuracy of 3 degc.

29. Temp. Ranges for Thermocouple
♦ Type Range Error limit
♦ J 0 to 750 2.2 dg or 0.75 %
♦ K -200 to 1250 2.2 dg or 0.75 %
♦ E -200 to 900 1.7 dg or 0.5 %
♦ T 0250 to 350 1 dg or 0.75 %

30. Process Control System

31. How PID control works
♦ Closed loop control means a method in
which a real-time measurement of the
process being controlled is constantly
fed back to the controlling device to
ensure that the value which is desired
is, in fact, being realized. The mission
of the controlling device is to make the
measured value, usually known as the
PROCESS VARIABLE, equal to the
desired value, usually known as the
SETPOINT.

32. Proportional Action
♦ Proportional Control, determines the
magnitude of the difference between
the SETPOINT and the PROCESS
VARIABLE (known as ERROR), and then
applies appropriate proportional
changes to the CONTROL VARIABLE to
eliminate ERROR.

33. Proportional Action
♦ Proportional mode is used to set basic Gain value
of the controller. It is expressed as
♦ 1. Proportional Gain- What is the % change of the
controller output relative to the % change in
controller Input. Gain
(Kc)=delta Output%/delta Input%
♦ 2. Proportional Band- What % of change of
controller Input span will cause a 100% change in
controller Output. PB=delta
Input(%span) for 100% Output
♦ Relation : PB=100/Gain OR Gain (Kc)=100%/PB
Small PB(% ) -- Minimize Offset,
High Gain(%) -- Possible cycling
Large PB (%) -- Large offset, Low

34. Proportional Action

35. Proportional Action

36. Proportional Action

37. Integral Action
♦ Integral Control examines the
offset of SETPOINT and the
PROCESS VARIABLE over time and
corrects it when and if necessary.
I.e
Controller output from the integral
or reset mode is function of the
duration of error.

38. Integral Action

39. Integral Action
♦ Integral or reset mode is always used with the
proportional mode.
♦ Integral or reset action expressed in terms of
Repeats per minute- How much times the
proportional action repeated in each minute.
Minutes per Repeat- How many minutes are
required for 1 repeat to occur.
Fast Reset – High Gain, Fast return to set point,
possible cycling.
Slow Reset – Low Gain, Slow return to set point,
Stable loop.

40. Integral Action

41. Integral Action

42. Derivative Action
♦ Derivative Control monitors the
rate of change of the PROCESS
VARIABLE and consequently
makes changes to the OUTPUT
VARIABLE to accommodate
unusual changes.
Some large and/or slow process do
not respond well to small change
in controller output.

43. Derivative Action
♦ Derivative Action is initiated whenever there is a
change in the rate of change of the error.
♦ Controller first compare the current PV with the
last value of the PV. If there is change in the slope
of the PV the controller determines what its output
would be at a future point in time. The derivative
mode immediately increases the output by that
amount (value of derivative setting in minutes).
♦ Large (Minutes) – High Gain, Large Output
change, Possible cycling.
♦ Small (Minutes) – Low Gain, Small Output
change, Stable loop.

44. Derivative Action

45. Derivative Action

46. Derivative Action

47. Control Algorithms commonly
used for process parameter
control

48. Cascade Control
♦ Cascade Control uses the output of the
primary controller to manipulate the set
point of the secondary controller as if it
were the final control element.

49. Cascade Control

50. Ratio Control
♦ Ratio control is used to ensure that two
or more flows are kept at the same ratio
even if the flows are changing.

51. Override Control
♦ Override control is used to take control
of an output from one loop to allow a
more important loop to manipulate the
output.

52. Programmable Logic Controller

53. Programmable Logic Controller
♦ Definition:
“PLC is a digitally operating electronic system
designed for use in an industrial environment
which uses a programmable memory for the
internal storage of instruction for implementing
specific functions to control various types of
process”.
♦ In the earlier days, the equipment was operated by
Electro-mechanical Relay mounted panel
♦ The PLC replaced Relay mounted panels

54. A PLC works by continually scanning a program. We can think
of this scan cycle as consisting of three important steps .
CHECK INPUT STATUS
EXECUTE PROGRAM
UPDATE OUTPUT STATUS
How does PLC works

55. Processor Architecture

56. Processor Architecture
♦ The main parts of PLC are:
1) CPU Board
2) Memory Module
3) Inputs module
4) Outputs module
5) Power Supply
6) Programming Terminal

57. PLC System Architecture
♦ Input to the PLC are mainly of two types.
- Digital Input: Proximity Switch, Pressure switch,
Temperature switch etc.
- Analog Input: 4 to 20 mA signals of Pressure,
Level, Temperature, Flow transmitters.
♦ Output form the PLC going to I/P converter of the
valve, Variable speed drives, Relay, Lamp
indication, Hooter, etc.
♦ The Digital and Analog input signals comes to the
Digital and Analog input card respectively

58. PLC System Architecture
♦ The Digital and Analog outputs are coming
from the Digital and Analog output cards
respectively.
♦ These cards are installed in Chassis called
Remote I/O Chassis
♦ The Remote I/O chassis is connected with
PLC thru Belden 9463 (blue Colour)

59. Signal Flow in PLC
♦ The Field Signals are connected with I/O
cards in RIO chassis
♦ Processor taking data from RIO chassis thru
Remote I/O link and stores in I/P image
tables / memory
♦ The data is being updated on every scan of
the PLC
♦ The data is processed in Processor
according to the program written

60. Signal Flow in PLC
♦ The result is transferred to the output cards
in RIO Chassis.
♦ The Output will be in the terms of 4-20mA
or Contacts.
♦ The Processor updates the data on every
scan, The scan time is in terms of
milliseconds (averagely 40 mS).

61. Signal Flow in PLC
♦ The scan of the processor means processor
doing input scan, then program scan, then
output scan, service communication and
housekeeping. The time taken for
completing this activities once is call scan
time

62. Signal Flow in PLC
♦ Processor Memory can be divided into two
parts
♦ One part contains data files which having
All Input/Output status and intermediate
flags
♦ Other consists of program files in which
ladder program has written

63. PLC Software
♦ The Software package can be loaded into
PC or Laptop
♦ The PC requires KT card and the Laptop
requires PCMK card.
♦ If KT/PCMK not available, then Processor
can communicate on COM port of
PC/laptop Serially thru CH0 on processor

64. Advantages of PLC
♦ The advantages of PLC over the Relay
Logic are:
- Less cabling
- Less space requirement
- Very High flexibility
- High reliability
- Easy diagnostic
- Very fast response time

65. Man Machine Interface
♦ The Operator interface monitor for Allen-
Bradley PLC is called IPDS
♦ The IPDS can
- Display Program rungs
- Display various digital indications
- Display Data table contents
- Status of Start/Stop of Motors
- Status of I/O, timers, counter, flags, etc.

66. Distributed Control System
(DCS)

67. 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/stations 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.

68. 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

69. Information Processing
M a n a g e m e n t
P r o d u c t io n r e p o r t ,
I n v e n t o r y r e p o r t ,
I n f o r m a t io n &
a p p li c a t io n
S p e c if ic c o n s u m p t io n
r e p o r t , Y ie ld a n d A c c o u n t in g
r e p o r t s a n d V a r ia n c e r e p o r t s
Q u a lit y in s u r a n c e r e p o r t s ( L I M S ) E n v
a n d p o llu t io n r e la t e d R e p o r t s
I n f o r m a t i o n M a n a g e m e n t & r e p o r t in g
H is t o r ia n s - T r e n d s , E v e n t r e c o r d e r s
D is t u r b a n c e r e c o r d e r s
O p t i m is a t i o n
A d v a n c e P r o c e s s C o n t r o l
H a z o p / R i s k M a n a g e m e n t
E m e r g e n c y S h u t d o w n S y s t e m s
A l a r m ,
M o n it o r in g ,
C o n t r o l,
R e g u l a t o r O N - O F F ,
I n t e r l o c k s
S t a r t - u p
P e r m i s s iv e
T r i p s
F IE L D : S i n g l e L o o p C o n t r o l le r s
F I E L D : T r a n s m it t e r s & f i e l d d e v ic e s -
S w i t c h e s , C o n t r o l v a l v e s
D is t r i b u t e d C o n t r o l S y s t e m
S u p e r v i s o r y C o n t r o l A n d D a t a
A c q u i s i t i o n S y s t e m
P r o g r a m m a b l e L o g i c
C o n t r o ll e r s
F IE L D
C o n t r o l
S y s t e m
S a f e t y
O p t i m is a t i o n
In f o r m a t i o n
E n t e r p r is e
B u s i n e s s

70. 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

71. Control Algorithm
– Analog Input / Output Block
– PID Block / Auto tune PID block
– Digital Input/Output Block
– Calculation Block / Advance Calculation Block
– Characterized 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

72. DCS Manufacturers
♦ ASEA BROWN BOWERI - ABB
♦ TATA HONEYWEL – TDC 3000
♦ FOXBORO - INVENSYS
♦ YOKOGOWA INDIA LIMITED - YIL
♦ ALLEN BRADLEY
♦ GE FANUC
♦ FISHER ROSEMOUNT- Delta V
♦ TOSHIBA - TOSDIC

73. DCS Architecture YOKOGAWA

74. Typical Signal Flow Diagram
JB = JUNCTION BOX SCC = SIGNAL COND. CARD
TB = TERMINATION BOX CFBS2 = CONTROL STATION
BAR= BARRIER COPSV = OPERATOR STATION
JB TB BAR SCC CFBS2
COPSV
JB TB BAR SCC CFBS2
From TX
CONTROL ROOMFIELD
To O/P

75. Final Control Element
(Control Valve)

76. What is Control Valve
This is a device used to modulate
flow of process fluid in line by
creating a variable pressure drop in
the line .

77. Control Valve Parts (Actuator)

78. Control Valve Parts (Body)

79. Control Valve Functions & Characteristics
♦ Fail-Open:A condition wherein the valve closure
member moves to an open position when the
actuating energy source fails.
♦ Fail-Closed: A condition wherein the valve
closure member moves to a closed position when
the actuating energy source fails.
♦ Fail-safe: A characteristic of a valve and its
actuator, which upon loss of actuating energy
supply, will cause a valve closure member to be
fully closed, fully open, or remain in the last
position, whichever position is defined as
necessary to protect the process.

80. Valve Flow Coefficient
VALVE Cv - No. Of US gallon [USG = 3.7 Liters] of
water per minute passing through the valve in full
open condition with 1 PSI pressure drop across the
valve at 15 deg C temp.
So essentially valve Cv is capacity of valve in terms of
water which helps us to identify suitable size
required for any fluid in any pressure / temp.
condition.
VALVE Kv - Quantity of water in M3/Hr. at
temperature between 5 to 40C that will flow through
the valve at a specified travel with a pressure drop of
1 Bar.
Kv = 0.856Cv

81. Types of Control Valves
Also valves may be further subdivided as shown below
BY SHAPE BY INTERNAL BY CHAR. BY GUIDING
GLOBE PLUG EQ% TOP
SINGLE SEAT
DOUBLE SEAT
BUTTERFLY CAGE LINEAR CAGE
ANGLE FULL BALL QUICK OPEN TOP & BOTTOM
SLANT SLEEVED PARABOLIC BUSH/BEARING
Y TYPE V BALL

82. Control Valve actuator
Actuator - Mechanism
which operates the valve
by receiving the control
signal.
Type of Actuator
Pneumatic - Spring
Diaphragm, Piston
Cylinder
Electrical - for ROVs
Hydraulic -

83. Valve Accessories
♦ VALVE POSITIONERS
– PNEUMATIC
– ELECTRONEUMATIC
– SMART DIGITAL
♦ PROXIMITY SWITCHES
– INDUCTIVE TYPE
– PNEUMATIC CAM OPERATED
♦ SOLENOID VALVES
– LATCHING/ NON-LATCHING
– WITH MANUAL OVERRIDE
♦ SIGNAL BOOSTERS
– PRESSURE
– VOLUME
♦ SIGNAL INVERTERS
♦ HANDWHEEL

84. Control Valve Leakage
Control Valve LeakageControl Valve Leakage --
This is basically the fluid which passesThis is basically the fluid which passes
through the valve when the valve is fullythrough the valve when the valve is fully
closed. This value however should not beclosed. This value however should not be
considered as the valve Cv at NIL Opening.considered as the valve Cv at NIL Opening.
So this leakage shall depend on the contact ofSo this leakage shall depend on the contact of
valve plug & seat with the seating forcevalve plug & seat with the seating force
applied for holding the plug over the seat.applied for holding the plug over the seat.

85. Control Valve Leakage
ANSI/FCI 70-2 Test Medium Pressure and temperature
Class II
Class III
Class IV
Class V Water Service DP at 10 to 52deg C
Port dia.
Bubbles per
Min.
mL per Min.
1 1 0.15
1 - 1/2 2 0.30
2 3 0.45
2 - 1/2 4 0.60
3 6 0.90
4 11 1.70
6 27 4.00
Maximum Leakage
0.5% valve capacity at full travel
0.1% valve capacity at full travel
0.01% valve capacity at full travel
0.0005ml/min/psid/in. port dia
Class VI
Service DP or 50 PSID
whichever is lower at 10 to
52deg C
Water / Air
Service DP or 50 PSID
whichever is lower at 10 to
52deg C
Air

86. Control valve Characteristic

87. VALVE Characteristic
Equal Percentage Characteristic:An inherent flow
characteristic that, for equal increments of rated
travel, will ideally give equal percentage changes
of the flow.
Linear Characteristic: An inherent flow
characteristic that can be represented by a straight
line on a rectangular plot of flow coefficient (Cv)
versus rated travel. Therefore equal increments of
travel provide equal increments of flow.
Quick Opening Characteristic: An inherent flow
characteristic in which a maximum flow
coefficient is achieved with minimal closure
member travel
On/Off -On/Off - Used mainly as Isolation valves (Pump
suction and ESD valves)

88. Standard TERMS
♦ ANSI: Abbreviation for American National
Standards Institute.
♦ API: American Petroleum Institute.
♦ ASME: American Society of Mechanical
Engineers.
♦ ASTM: American society for testing & Materials.
♦ ISA: Instrument Society of America.
♦ OSHA: Occupational safety & Health ACT (USA)
♦ FCI: Fluid Control Institute.

89. Hazard & Its Causes/ TypesHazard & Its Causes/ Types
♦ Introduction:Introduction: Any area in plant where
manufacturing processes emit/ may emit gases,
vapours or mists if mixed with air in correct
proportions will produce explosive medium.
♦ For an ignition to occur there must be:For an ignition to occur there must be:
– A Hazard
– A Source of Energy (Ignition or Hot Surface)
– Air (To Support Combustion)

90. Standards Followed:Standards Followed:
♦ Europe:Europe: CENELEC & IEC(International
Electrotechnical Commission)
♦ North America:North America: NEC
♦ IEC : Gases and Vapours in two groupsIEC : Gases and Vapours in two groups:
– GR IGR I :: Mining (Sub-Surface) Industry
– GR IIGR II :: Surface Industry; Sub-Groups
A,B,C.
– As per NECAs per NEC::
– Class 1Class 1:: Gases & Vapours; further divided into 4
groups: A,B,C,D.
– Class 2Class 2:: Combustible Dusts; further divided into 3
groups based on their resistivity: G,E,F.

91. Gas GroupingGas Grouping
Gases belonging to IIC are most dangerous with severity decreasing toGases belonging to IIC are most dangerous with severity decreasing to
IIA.IIA.
Representative Gas As per IEC
(EU)
As per NEC
(US)
Methane I D
Propane IIA D
Ethylene IIB C
Hydrogen IIC B
Carbon Disulphide IIC -
Acetylene IIC A

92. Flammable LiquidsFlammable Liquids
Classified on basis of Flash Point.
Class A :Class A : Flash Pt < 23o
C. They produce large
volumes of vapour
Class B :Class B : 23o
C<Flash Pt<65o
C
Class C :Class C : 65o
C<Flash Pt<93o
C

93. BasisBasis
Probability of presence of explosive mixture.
IECIEC: 3 zones (Zone : 0,1,2)
Zone 0:Zone 0: Explosive Mixtures continuously present / Present
for long (>1000 Hrs/Yr). e.g. Inside Tanks, Vessels etc.
Zone 1:Zone 1: Explosive Mixtures likely to occur in normal
operation / (Between 10 to 1000 Hrs/ Yr). eg Production
Area, area surrounding zone 0.
Zone 2:Zone 2: Explosive Mixtures not likely to occur /occur short
duration in normal operation (<10 Hrs/ Yr).

94. NEC:NEC: 2 Divisions (Div: 1 & 2)
Division I:Division I: Comprising of Area Same as Zone 0 & 1.
Division II:Division II: Comprising of Area Same as Zone 2.
4. Area Classification4. Area Classification
The max surface temp. of exposed surface of equipment mustThe max surface temp. of exposed surface of equipment must
always be lower than Auto-Ignition Temp of the Prevailingalways be lower than Auto-Ignition Temp of the Prevailing
Gas.Gas.
Class
T1
T2
T3
T4
T5
Temperature(o
C)
450
300
200
135
100

95. Trouble shooting

96. BCC-003-7
BCC-071-6
FIELD JUCTION BOX BARRIER RACK 20 PLC
CENTUM
2CFBS2 STN NO : 2
CNC
A+
B
C-
CR 5
R3 -9
CN 1
CN 2
A+
B
C-
CCO
R3 -10
F3 - 1 - 5
F3 - 2 - 5
MAC2
MAC2
R1 - 96 1
24
3
MTL 728 +
7
8
9
I / P
--
+
TI 3106
TV 3106
AS
JBE 209
11
A
B
C
9
10
12
R3 - 38
BARD 300
A
B
C
1
3
JBR 607
KS1
KS1AS
VIEWHOME
Conventional Closed Loop

97. FIELD JUCTION BOX BARRIER RACK 20 PLC
CENTUM
3CFBS2 STN NO : 3
35
33
34
R 4 - 44
BARD 300
A
B
C
1
3
JBR 604
TE 1704
CNC
A
B
C
CR 5
R 3 - 15
CN 1
CN 2
F 6 - 3 – 6
VM 1
KS 2
BCC – 082 – 3
2
A
B
C
Conventional Open Loop

98. RELAY
XL 1802
F2 - 13
2
10
1
11 9
7
3
6
FIELD BARRIER RACK 20 PLC
CENTUM
3CFBS2 STN NO : 3
--
+
S
XL 1802
LIMIT
SWITCH
+
_
110 V DC
35
36
FT 1
6A
6B
*
TB 16
FZ 2
RELAY / MARSHAL RACK 31
13
RPC - 102 - 2
PLC -1
TERMINAL
NO
1 T 1 - 53
I / O NO.
I 000 214
RPC - 202 - 2
PLC -2
TERMINAL
NO
1 T 3 - 53
I / O NO.
I 000 214
13
RT 1A
RT 1B
F 1 - 5 - 6
ST 2KS 2
110 V DC
SHUT DOWN RACK 30
+
VIEWHOME
DCS & PLC
Interface

99. Troubleshooting
♦ Start with the fail mode of the valve.
1. If the valve fails closed and is leaking...
• Disconnect the positioner or controller input.
• If the valve has a hand wheel, check to see that it
is backed out.
• Check to see if the bench range is correct.
• Check to see if there is trash in, or damage to, the
valve seat.
♦ 2. Next check the positioner.
♦ 3. Next check the controller.

100. Bath Tub curve Analysis

101. Bath Tub Curve.
∀ The first part is a decreasing failure rate,
known as early failures or infant mortality.
∀ The second part is a constant failure rate,
known as random failures.
∀ The third part is an increasing failure rate,
known as wear-out failures.

102. Maintenance

103. The Five stages of maintenance
♦ 1- No action until equipment fails
♦ 2- Routine service oil and grease�
♦ 3- Inspection and preventive repair
♦ 4- Equipment Re-Engineering
♦ 5- Predictive Maintenance

104. What is maintenance
♦ Maintenance is the action associated with
equipment repair after it is broken.
♦ Dictionary meaning: The work of keeping
something in proper condition—upkeep.

105. Reactive maintenance
♦ Reactive maintenance is basically the “run
it till it breaks” maintenance mode.
♦ No actions or efforts are taken to maintain
the equipment-as designer specify its life.
♦ > 55% -- Reactive
♦ 31% -- Preventative
♦ 12%-- predictive
♦ 2% --others

106. Preventative maintenance
♦ Action performed on a time or machine run
based schedule that detect, preclude or
mitigate degradation of component with the
aim of sustaining or extending its useful
life.

107. Predictive Maintenance
♦ Measurement that detect the onset of a
degradation mechanism thereby allowing
casual stressors to be eliminated or
controlled prior to any significant
deterioration in the component physical
state.

108. Reliability Centered maint.
♦ A process used to determine the
maintenance requirements of any physical
asset in its operating context.

109. Maintenance Practices
♦ Calibration of field instruments
♦ Check sheets
♦ LLF
♦ Break down maintenance.
♦ Preventative maintenance.
♦ Chance based maintenance.

110. Maintenance Practices
♦ Calibration carried out in house in plants
♦ Utilities flow instruments calibrated from
CES(I).
♦ Daily, weekly, monthly checks carried out
in Bagging sections.
♦ LLFs carried out once in month.
♦ Break down carried out in house.

111. Test & Measuring Instruments.
♦ Identified Test & Measuring instrument’s
calibration is carried out once in a year
through external agency.
♦ Calibration, Certification & traceability
certificates are maintained for record
purpose.

112. PM, RM, SRA activities
♦ PM & RM for DCS & PLCs carried out
through OEMs.
♦ Modification related to FCOs, Shutdown
Jobs done through SRA- which includes
Tubing, welding, fabrication, etc.
♦ Control valve maint. activities in mass
carried out through SRA by external agency
during long shutdown.

113. Statutory related activities
♦ LEL routine check carried out 3 times in a year
through OEM.
♦ Statutory requirements like weight & measure,
Nucleonic instruments records are maintained
(half yearly as per BSC check sheet).
♦ Weight & measure- every year through external
agency.
♦ Nucleonic gauges status report sent to BARC
twice in a year.

114. Statutory related activities
♦ Custody meters are calibrated through FCRI
flow lab & certificate are maintained for
record purpose.
♦ Stamping of platform weigh scales, Net
weighers, checkweighers are done by legal
metrology department & coordinated by
CES-I.

115. Interlock checking
♦ Plant interlocks are checked opportunity
base/annual S/D/ short shutdown witnessed
by operation & maint-I. Signed record kept
in C/R & with Inst. dept.
♦ Alarm, trip settings, bypass are done as per
BSC check sheet authorized by CTS &
plant HOD.

116. CES-I coordination
♦ FIR/FAR
♦ FCO
♦ Statutory coordination
♦ Inst calibration during shutdown.
♦ Coordination of activities like seminars,
presentations, involvement of S/D activities.

117. Maintenance Excellence
♦ A well executed drive towards maintenance
excellence can…
· Achieve Availabilities Of 90%-98%
· Reduce Failure Rate 50%-90%
· Increase Capacity 10%-30%
· Improve Quality
· Reduce Frustration

118. THANK YOU