This document defines and classifies transducers. It states that a transducer converts one form of energy to another and contains sensing and transduction elements. Transducers are classified as primary/secondary, active/passive, analog/digital, and mechanical/electrical. Primary transducers send measurements and convert them to other variables like displacement or strain, whose output forms the input of another transducer. Secondary transducers convert the output of the first transducer into an electrical output. Piezoelectric transducers are given as an example of an active transducer as they generate a voltage from an applied force without an external power source.

1. School of Engineering and Technology
Srinagar Garhwal
PREPARED BY:
ANKIT THAPLIYAL
BRANCH- MECHANICAL

2. THE TRANSDUCER CAN BE DEFINED AS A DEVICE WHICH
IS USED FOR THE CONVERTING ONE FORM OF ENERGY
INTO ANOTHER FORM.

3. •Transducer contains two parts that are closely related to each
other i.e. the sensing element and transduction element.
•The sensing element is called as the sensor. It is device
producing measurable response to change in physical conditions.
•The transduction element convert the sensor output to suitable
electrical form.
BLOCK DIAGRAM OF TRANSDUCERS

4. Classification of transducers
Primary Active Analog And Electrical
And And And And
Secondary Passive Digital Mechanical

5. PRIMARY AND SECONDARY TRANSDUCER
The transducer which sends the measurement and convert them into another variables(like
displacement,strain etc) and whose output forms the input of another transducer is called
as primary transducer.
The transducer which convert the output of first transducer into an electrical output called
secondary transducer.

6. ACTIVE TRANSDUCERS
PIEZOELECTRIC TRANSDUCER - when an external force is applied on to a quartz
crystal.there will be a change in the voltage generated across the surface.this
change is measured by its corresponding value of sound or vibration.
When there is no need for any source then these type of transducer are active
transducer.
Example: Piezoelectric crystal

7. Passive Transducers
Passive Transducers :
I. These transducers need external source of
power for their operation. So they are not self
generating type transducers.
II. A DC power supply or an audio frequency
generator is used as an external power source.
III. These transducers produce the output signal in
the form of variation in resistance, capacitance,
inductance or some other electrical parameter in
response to the quantity to be measured.

8. Analog And Digital Transducers
Analog transducers convert input signal into output signal,which is a
continuous function of time such as THERMISTOR,STRAIN
GAUGE,LVDT,THERMOCOUPLE etc.
Digital Transducers convert input signal into output signal in the form of
pulses.it gives discrete output.
Example: Applications Turbine meter used in flow measurement.
Strain gauge

9. THERMOCOUPLE
Thermocouples are based on the principle that two wires made of
dissimilar materials connected at either end will generate a potential
between the two ends that is a function of the materials and
temperature difference between the two ends (also called the
seebeck effect).

10. THANK YOU