How To Exam?

# Bengal Engineering and Science University 2006 B.E Computer Science and Engineering Transducer and Instrumentation - Question Paper

Friday, 18 January 2013 12:55Web

the ques. paper is with the attachment.

Ex/BESUS/ EE-611/06

B.E. (CST) Part-Ill 6th Semester Examination, 2006

Transducer and Instrumentation (EE-611)

Time : 3 hours    Full Marks : 100

Use separate answerscript_for each half. Answer SIX questions, taking THREE _ from each half. Two marks are reserved_for neatness in each half.

FIRST HALF

1. a) Explain the following terms with examples :

(i) Primary & secondary transducers, (ii) Active and passive transducers,

(iii) Analog and digital transducers.

b)    State the advantages of "electrical transducers".

c)    Describe the block diagram of a data acquisition system and explain the function of each block.    (6+3+7)

~T. "a") DistihAuTsffBetween a "resistance strain gauge" and "semiconductor strain gauge" on counts of linearity, accuracy, sensitivity and temperature dependance.

b)    State the application areas of strain gauges.

c)    A resistance wire strain gauge with a gauge factor of 2 is bonded to a steel structural member subjected to a stress of 100 MN/m2. The modulus of elasticity of steel is 200 GN/m2. Calculate the percentage change in the value of the gauge resistance due to the applied stress.    (7+3+6)

3. a) Draw and explain, how the LVDT can be used for the measurement of linear displacement.

(c) The output of an LVDT is connected to a 5 V voltmeter through an amplifier with amplification factor 250. An output of 2mV appears accross the terminal of LVDT, when the core moves through a distance of 0.5 mm. Calculate the sensitivity of the LVDT and the whole set up. The mili-voltmeter scale has 100 divisions. The scale can be read to V5 of a division. Calculate the resolution of the instrument.

(6+3+7)

4. a) Classify and briefly describe the various types of capacitive transducers.

b) How the parallel plate capacitor type transducer is used for liquid level detection. Draw the scheme and analyse.    (8+8)

Write short notes on any two of the following :

a)    Synchros

b)    Digital transducers

c)    Piezo-electric transducers

d)    Temperature sensors.

SECOND HALF

6. a) Design a second order low pas filter (Butterworth type) with a cut-off frequency of 1 kHz. Select capacitor C of value 0.16 micro-Farad. What is the dc gain of the filter?

b) If one has to design a second order high pass filter with a low frequency cut off at 1 kHz, what changes are to be made in the circuit for low pass filter?

(10+2+2+2)

7.    a) Design a square-wave generator using OPAMP and R, C for 10 kHz oscillation.

Take feedback factor (3 equal to 0.5. Choose capacitance of the order of 1 microFarad.

b) How do you modify the circuit for square wave generator to get a monostable multivibrator? If Vz is equal to 10 V, what will be the delay time with the same charge discharge circuit as in the square-wave generator? (8+4+4)

8.    a) What are the two conditions for getting sustained sinusoidal oscillation from

the output of an amplifier with feedback?

b) Design a Wein-Bridge sinusoidal oscillator circuit for 10 kHz oscillation. Select values of C in the order of micro-Farad and values of R in the order of

(8+8)

K ohms.

9.    a) What are the essential properties of an Instrumentation amplifier?

b)    Why a simple subtractor circuit using single OPAMP is not an ideal instrumentation amplifier.

c)    Explain the operation of a three-opamp realisation of Instrumentation amplifier.

(6+4+6)

10.    Write short notes on any two :    (8+8)

(a)    V-I converter with grounded load

(b)    Improved S/H circuit

(c)    Isolation amplifier