Transcript Displacement Measurement

TOPIC:
DISPLACEMENT
MEASUREMENT
PRESENTED BY:
SURESH VENKATTU
ROLL NO: 1817
Displacement
Measurement
• Potentiometer
• Capacitive Transducer.
• Rotary variable differential transformer
(RVDT)\
Linear Variable-Differential
Transformer (LVDT)
POTENTIOMETER
Linear potentiometer is a device
in which the resistance varies as
a function of the position of a
slider.
APPLICATION OF
POTENTIOMETER
ADVANTAGES OF
POTENTIOMETER
•Inexpensive.
•Simple to operate.
•Useful for measurement of
large amplitudes of
displacement.
•Electrical efficiency is very
high.
DISADVANTAGE OF
POTENTIOMETER
Capacitive
Transducer
The capacitance of the capacitor
varies as the material comes
between two plates of capacitor
and the presence of something is
measured by capacitance.
Rotary variable
differential
transformer(RVDT)
A=Primary winding
B=Secondary winging
Linear Variable-Differential
Transformer (LVDT)
Vo=V1-V2
V1
V2
X=0
V2 = V1
Vi
Both the secondary windings are equal which results
in net output is equal to zero
Linear Variable-Differential
Transformer (LVDT)
(while moving left)
Vo=V1-V2
V1
V2
-x
V1 > V2
Vi
the emf voltage induced in the secondary
coil is greater when compared to the emf
induced in the secondary coil 2.
Linear Variable-Differential
Transformer (LVDT)
(while moving right)
Vo=V1-V2
V1
V2
+x
V2 > V1
Vi
The emf induced in the secondary
coil 2 is greater when compared to
the emf voltage induced in the
secondary coil