electrical transducers · the length, area and resistivity of the metal. urvish soni. advantages of...
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ElectricalTransducersTransducers
Urvish Soni
http://slideplayer.com/slide/2541370/
Urvish Soni
ElectricalTransducersTransducers
Urvish Soni
http://slideplayer.com/slide/2541370/
Urvish Soni
Urvish SoniUrvish Soni
Advantages of Electrical Transducer
• Electrical amplification can be easily done.
• Effects of friction are minimised.
• The output can be indicated and recorded sensing medium.
• The output can be modified to meet the requirements of the indicating or controlling units.
• Signal conditioning is easy.
• The electrical or electronic system can be controlled with a very power level.
• The electrical output can be easily used, transmitted purpose of measurement.
Urvish Soni
Advantages of Electrical Transducer
can be easily done.
The output can be indicated and recorded remotely at a distance from the
to meet the requirements of the indicating or
The electrical or electronic system can be controlled with a very small
easily used, transmitted and processed for the
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Different types of electrical transducers
• Resistive Transducers
• Inductive Transducers
• LVDT, RVDT
• Capacitive Transducers• Capacitive Transducers
• Piezoelectric Transducers
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electrical transducers
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Resistive Transducers
• The transducer whose resistance varies because of the environmental effects such type of transducer is known as the resistive transducer.
• The resistive transducer is used for measuring the physical quantities like temperature, displacement, vibration etc.like temperature, displacement, vibration etc.
• The measurement of the physical quantity is quite difficult. The resistive Transducers converts the physical quantities into variable resistance which is easily measured by the meters.
• The resistive transducer can work both as the primary as well as the secondary transducer.
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Resistive Transducers
The transducer whose resistance varies because of the environmental effects such type of transducer is known as the resistive transducer.
The resistive transducer is used for measuring the physical quantities like temperature, displacement, vibration etc.like temperature, displacement, vibration etc.
The measurement of the physical quantity is quite difficult. The converts the physical quantities into variable
resistance which is easily measured by the meters.
The resistive transducer can work both as the primary as well as the
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Working Principle of Resistive Transducer
• The resistive transducer element works on the principle that the resistance of the element is directly proportional to the length of the conductor and inversely proportional to the area of the conductor.
• Where R – resistance in ohms.A – cross-section area of the conductor in meter square.L – Length of the conductor in meter square.ρ – the resistivity of the conductor in materials in ohm meter.
• The resistive transducer is designed by considering the variation of the length, area and resistivity of the metal.
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Working Principle of Resistive Transducer
The resistive transducer element works on the principle that the resistance of the element is directly proportional to the length of the conductor and inversely proportional to the area of the conductor.
section area of the conductor in meter square.Length of the conductor in meter square.the resistivity of the conductor in materials in ohm meter.
The resistive transducer is designed by considering the variation of the length, area and resistivity of the metal.
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Advantages of Resistive Transducer
�Both the AC and DC, current or voltage is appropriate for the measurement of variable resistance.
�The resistive transducer gives the fast response.
�It is available in various sizes and having a high range of �It is available in various sizes and having a high range of resistance.
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Advantages of Resistive Transducer
Both the AC and DC, current or voltage is appropriate for the measurement of variable resistance.
The resistive transducer gives the fast response.
It is available in various sizes and having a high range of It is available in various sizes and having a high range of
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Applications of Resistive Transducer
�Potentiometer
�Strain gauges
�Resistance ThermometerResistance Thermometer
�Thermistor
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Applications of Resistive Transducer
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LVDT type
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LVDT type
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RVDT
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Resistive Transducers
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Resistive Transducers
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Capacitance type
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Principle of Operation
• The equations below express the capacitance between the plates of a capacitor
• Where A – overlapping area of plates in md – the distance between two plates in meterε – permittivity of the medium in F/mεr – relative permittivityε0 – the permittivity of free space
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Principle of Operation
The equations below express the capacitance between the plates of a
overlapping area of plates in m2
the distance between two plates in meterpermittivity of the medium in F/m
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Working
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Advantage of Capacitive Transducer
�It requires an external force for operation and hence very useful for small systems.
�The capacitive transducer is very sensitive
�It gives good frequency response because of which it is used for the �It gives good frequency response because of which it is used for the dynamic study.
�The transducer has high input impedance hence they have a small loading effect.
�It requires small output power for operation.
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Advantage of Capacitive Transducer
for operation and hence very useful for
very sensitive.
because of which it is used for the because of which it is used for the
The transducer has high input impedance hence they have a small
for operation.
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Disadvantages of capacitive Transducer
�The metallic parts of the transducers require insulation.
�The frame of the capacitor requires of the stray magnetic field.
�Sometimes the transducer shows the �Sometimes the transducer shows the of the edge effect which is controlled by using the guard ring.
�The cable connecting across the transducer causes an error.
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Disadvantages of capacitive Transducer
s of the transducers require insulation.
The frame of the capacitor requires earthing for reducing the effect
Sometimes the transducer shows the nonlinear behaviours because Sometimes the transducer shows the nonlinear behaviours because of the edge effect which is controlled by using the guard ring.
The cable connecting across the transducer causes an error.
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Piezo electric•Piezoelectric Effectcertain materialselectric charge in responsemechanical stress.mechanical stress.
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Effect is the ability ofto generate an
response to applied
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Piezo electric type Sensor
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Principles: ∆ Pressure � ∆ Charge �
Applications: measurements with high accuracy, good repeatability, high resolution.
type Sensor
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� ∆ Voltage
: measurements with high accuracy, good repeatability, high resolution.
Piezo electric Material
• Quartz
• Cane sugar
• Rochelle salt
• Topaz• Topaz
• Tourmaline
• Bone
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electric Material
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Strain Gauge Transducers• Unbonded
• bonded
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Strain Gauge Transducers
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Application
• Stress measurement
• Vibration measurement
• Torque measurement
• Bending and deflection measurement• Bending and deflection measurement
• Compression and Tension measurement
• Strain measurement
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Bending and deflection measurementBending and deflection measurement
Compression and Tension measurement
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