This document discusses different types of transducers, including their basic construction, classification, and applications. It describes how transducers convert one form of energy into another, such as converting non-electrical quantities like force, displacement, and temperature into equivalent electrical signals. Transducers are classified as primary or secondary, passive or active, and analog or digital. Examples of common transducers discussed include thermistors, LVDTs, strain gauges, and RTDs. Criteria for selecting transducers and their advantages and disadvantages are also summarized. Transducers have various applications and are useful for converting energy in devices like microphones, speakers, alarms, and instruments that measure pressure and displacement.

1. PRESENTEDBY : HARSH YADAV
[2020031068]
B.Tech 3rd year
Seminar on
TRANSDUCER

2. CONTENTS
WHAT IS TRANSDUCER
ELECTRICAL TRANSDUCER
BASIC CONSTRUCTION OF TRANSDUCERS
CLASSIFICATION OF TRANSDUCERS
THERMISTORS
LVDT
STRAIN GAUGE
RTD
SELECTION CRITERIA OF THE TRANSDUCERS
ADVATAGES AND DISADVANTAGES
APPLICATIONS AND CONCLUSION

3. WHAT IS TRANSDUCER
The transducer is defined as the device which convert the one
form of energy into another form of the energy
Example:
● Temperature transducers
● Thermocouples
● Resistance-Temperature Detectors (RTD)
● Thermistors
● Resistive position transducers
● Displacement transducers
● Strain gauge

4. ELECTRICAL TRANSDUCERS
The electrical transducers is one which converts the non-
electrical quantity into the equivalent electrical quantity.
Non-electrical quantity such as force, displacement,
stress, temperature.
Electrical quantity such as current , voltage.

5. BASIC CONSTRUCTION OF
TRANSDUCERS
It consist of two important parts
● Sensing element.
● Transduction element.

6. CLASSIFICATION OF
TRANSDUCERS
On the basis of transduction form used :-
● As primary and secondary transducers.
● As passive and active transducers.
● As analog and digital transducers.

7. Primary and secondary transducers
Transducer which are directly in contact with the
measurand is known as Primary Transducer.
Example : Bourdon tube
Transducer which are not directly in contact with the
measurand is known as Secondary Transducer.
Example : LVDT

8. Passive and Active Transducers
If transducers derive the power require for transduction
from an power source, then this kind of transducer are
known as Passive transducer.
Example : LVDT
When there is no need for any source then these type
of transducers are Active transducers.
Example : Piezoelectric crystal

9. ANALOG AND DIGITAL
Analog transducer converts input
signal into output signal, which is a
continuous function of time such as
thermistor, strain gauge, LVDT etc.
Digital transducer
converts input signal into
the output signal of the
form of pulse.
e.g. it gives discrete

10. THERMISTORS
● Thermistors are used for the
measurement of precision
temperature
LVDT (Linear Variable Differential Transformer )
● It is a inductive type transducer
which is used to convert the linear
displacement into electrical signal.

11. STRAIN GAUGE
I t works on Piezoresistive effect.
These are used for measurement
of stress and strain
RESISTANCE TEMPERATURE
DETECTOR
It is used for measuring
temperature.
It has great stability,
accuracy and
repeatability.

12. SELECTION CRITERIA OF THE
TRANSDUCERS
● Operating principle
● Sensitivity
● Operating range
● Accuracy
● Errors
● Environmental capability
● Insensitive to unwanted Signal
● Stability

13. ADVANTAGES
● Power requirement is very low for controlling the
electrical system.
● Output can be indicated and recorded remotely from the
sensing element.
● Electrical amplification can be easily done.
● An amplifier may be used to amplify the electrical
signal according to requirement.

14. DISADVANTAGES
● Their cost is high
● Thermistors are unsuitable for wide temperature
● Relative large displacement is required for
appreciable output for LVDT
● Bourdon tubes do not provide the precise
measurement.
● RTD produce mechanical vibrations.

15. APPLICATION AND CONCLUSION
● Transducers are used to convert one form energy to
another.
● All the transducers are very useful in all the
application such as
● Microphone , speaker
● Alarms
● Audio/video equipment
● Pressure indication
● Measurement of displacement etc.