The document provides an overview of a short term training program on industrial instrumentation. It discusses key topics that will be covered including basic measurement concepts, transducers and their classification, and measurement of variables like displacement, strain, pressure, flow, temperature, force and torque. It also outlines the elements of a measurement system, types of transducers, instrumentation amplifiers and features of a typical instrumentation system.

1. Shot Term Training
Programme on
Industrial Instrumentation
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2. Syllabus
Basic concept of measurement, Transducers and their
classification, Measurement of non-electrical quantities
like Angular and Linear Displacement, Strain,
Vibration, Pressure, Liquid flow, Temperature, Force
and Torque. Instrumentation amplifiers, Data
acquisition and conversion, Digital signal transmission
and processing, Microprocessor based instrumentation.
Input and output devices and Displays.
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3. INTRODUCTION
An instrumentation system is an assembly of
various instruments and components
interconnected to measure analyse and
control the electrical, thermal hydraulic and
other non-electrical physical quantities.
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4. Elements of Measurement System
The whole operation can be described in
terms of three functional elements. Each
functional element is made up of a distinct
component or group of components, which
performs required and definite steps in
measurement. These may be taken as basic
elements, whose scope is determined by their
functioning rather than their construction.
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5. Elements of Measurement System
 Primary sensing element
 Variable conversion element
 Data-presentation element
 Terminating stage
 Signal Conditioning
 Transmitting element
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6. Primary sensing element
The quantity under measurement makes its
first contact with primary sensing element of
a measurement system. Immediately after this
a transducer converts measured into an
analogous electrical signal. This is true in
most of the cases but in many cases the
measured quantity is directly converted into
an electrical quantity by a transducer.
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7. Variable conversion element
The output of the primary sensing element may
be any kind of electrical signal. It may be a voltage, a
frequency or some other electrical parameter. Often this
output does not suit to the system. For the instrument to
perform the desired function, it may be necessary to
convert this output to some other suitable form while
retaining the original signal. The function of variable
manipulation element is to manipulate the signal .
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8. Data-presentation element
The information about the quantity under
measurement has to be conveyed to the
personnel handling the instrument or the
system for monitoring control, or analysis
purposes. The information conveyed must be
in a form intelligible to the personnel.
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9. Data-presentation element cont..
These devices may be analogue or digital
indicating instruments like
 Ammeters
 Recorders like magnetic tapes,
 High speed camera
 Storage type CRT
 Printers
 Analogue and digital computers.
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10. Terminating stage
The final stage in a measurement system is
known as terminating stage.
When a control device is used for the final
measurement stage it is necessary to apply
some feedback to the input signal to
accomplish the control objectives.
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11. Signal Conditioning
Many a times one has to perform certain operations
on the signal before it is transmitted further. These
processes may be linear like amplification, alternation,
integration, differentiation addition and subtraction.
Some non-linear processes like modulation, detection,
sampling filtering, chopping and clipping etc. are
performed on the signal to bring to the desired form.
This is called signal conditioning.
In fact the element that follows the primary sensing
element in any instrument or instrumentation system
should be called signal-conditioning element.
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12. Transmitting element
When the elements of an instrument are
physically separated, it becomes necessary to
transmit data from one to another.
The element that performs this function is
called a transmitting element.
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13. Typical Instrumentation System
Consists of following operation.
Monitoring processes: - An instrumentation
system has an essential function of monitoring
the process. It simply indicates the value or
condition of parameter under the study in the
process.
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14. Process Control
In order to control the process variables like
temperature, pressure, humidity etc. these quantities
must be measured at the desired location in the
processing plant. They are compared with the reference
or desired signal and the error signal is amplified to
operate the actuator in controlling the process. The
corrective action goes on till the controlled output is
same as the desired output, in that case the error signal
will be zero and the actuator will not operate.
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15. TRANSDUCERS
A device, which converts one form of energy
into another form of energy, is called transducer.
For the field of electrical instrumentation
transducer is defined as a device, which converts
a physical quantity (or a physical condition) into
an electrical signal Transducer is often referred
as pick-up.
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16. Type of Transducers
 Primary Transducers
 Secondary Transducers
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17. Primary transducers
Primary transducers are detectors, which sense
a physical phenomenon.
The example of primary transducer is a
thermocouple, which senses the radiant energy
and directly converts it into an analogous
electrical output, which is a voltage.
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18. Secondary transducers
Secondary transducers convert the analogous
output into on electrical signal.
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19. Classification of transducers
The transducers can be active, that is self
generating type or passive, that is externally
powered.
Passive transducers derive the power required
for energy conversion from an external power
source. Potentiometers are the examples of
passive transducers.
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20. Active transducers
(i) Thermoelectric,
(ii) Piezoelectric,
(iii) Photovoltaic
(iv) Magnatostrictive,
(v) Electro kinetic
(vi) Electrodynamic,
(vii) Electromagnetic,
(viii) Pyroelectric,
(ix) Galvanic
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21. Passive transducers
(i) Resistive (viii) Hall effect
(ii) Inductive (ix) Synchro
(iii) Capacitive (x) Gyro
(iv) Photoconductive (xi) Radio active
(v) Magneto resistive absorption
(vi) Thermo resistive (xii) Ionic conduction
(vii) Elastoresistive
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22. Basic requirements of Transducers
1. Ruggedness
2. Linearity
3. Repeatability
4. Convenient instrumentation
5. High stability & reliability
6. Good dynamic response
7. Excellent mechanical characteristics
8. Built-in integrated device with noise and
other defects minimized
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23. Types of Detectors
 Electrical Transducers
 Pressure Transducers
 Piezzo-electric Transducers
 Oscillation transducers
 Inductive Transducer
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24. Advantages of Electrical transducer
over mechanical transducers
1. Minimized friction
2. Minimized mass-inertia effect
3. Easy Electrical amplification
4. Very small power electrical/electronic system controlled
5. The electrical output can be easily used, transmitted and
processed for the purpose of measurement.
6. Miniaturization due to integrated circuits and use of
microprocessors.
7. Easy Data transmission etc.
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25. MEASUREMENT
OF
DISPLACEMENT
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26. Major electrical transducers for
displacement measurement
 Variable resistance-
Potentiometric/strain gauge
 Variable inductance-LVDT/
variable reluctance
 Variable capacitance
 Synchros and resolvers
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27. Advantages of Synchros and resolvers
i. Infinite resolution
ii. No wear of rotation, except at slip rings
iii. System operating at much higher speed
iv. Relatively insensitive characteristics to
stray cable capacitances
v. High reliability and accuracy
vi. Useful operating angle of 360 degree and
capable of continuous rotations.
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28. MEASUREMENT
OF
STRAIN
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29. Types of strain gauges
Mechanical gauges
Optical gauges
Electrical strain gauges
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30. Types of electrical strain gauges
 Wire gauges
i. Flat grid type
ii. Wrap around type
iii. Single wire gauge
iv. Woven type
 Unbonded Strain gauges
 Foil gauges
 Semiconductor strain gauges
 Thin film gauges
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31. MEASUREMENT
OF
PRESSURE
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32. Classification of transducers
1. Gravitational i.e. Manometer
2. Elastic type
Diaphragms
Capsule
Bourdon tube
Bellows
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33. Transduction methods:
1. Potentiometric Device
2. Strain Gauge transducer
3. Variable reluctance Sensor
4. LVDT type transducer
5. Variable capacitance Device
6. Thin Film Pressure transducer
7. Force Balance transducer
8. Piezoelectric Pressure Transducer
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34. MEASUREMENT
OF
FLOW
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35. Classification of Flow meters
1. Head type flow meter based on differential pressure
measurement i.e.Orifice plate, Ventury tube, Flow nozzle
and Pitot tube
2. Electromagnetic flow meter
3. Rotameter (Variable area meter)
4. Mechanical flow meter
5. Anemometer
6. Ultrasonic flow meter
7. Vortex flow meter
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36. MEASUREMENT
OF
TEMPERATURE
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37. Types of Temperature sensors
1. Mechanical temperature sensors
i. Liquid in glass thermometer
ii. Liquid filled systems
iii. Vapour pressure thermometer
2. Resistance type temperature sensors
3. Platinum resistance thermometer
4. Thermocouples
5. Thermisters
6. Solid state sensors
7. Quartz thermometer
8. Radiation thermometer
9. Optical pyrometer
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38. MEASUREMENT
OF
FORCE AND TORQUE
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39. Types of transducers
1. Force Measuring sensor – Load cell:
i. Column type device
ii. Proving rings
iii. Cantilever beam
iv. Shear type load cell
v. Pressducer
2. Digital force transducer
3. Force balance device
4. Hydraulic load cell
5. Electronic weighing system
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40. Torque measuring transducers
1. Absorption type
2. Transmission type
3. Stress type
4. Deflection type
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41. INSTRUMENTATION
AMPLIFIER
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42. Important features
i. Selectable gain with high gain accuracy and
gain linearity
ii. Differential input capability with high
common mode rejection, even with sources
having unbalance high out put impedances
iii. High stability of gain with low temperature
coefficient
iv. Low DC offset and drift errors referred to
input
v. Low out put impedance
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