AMIETE – ET (NEW SCHEME) – Code: AE60
Subject: INSTRUMENTATION AND MEASUREMENTS
Time: 3 Hours Max. Marks: 100
NOTE: There are 9 Questions in all.
· Question 1 is compulsory and
carries 20 marks. Answer to Q.1 must be written in the space provided for it in
the answer book supplied and nowhere else.
· Out of the remaining EIGHT
Questions, answer any FIVE Questions. Each question carries 16 marks.
· Any required data not
explicitly given, may be suitably assumed and stated.
Q.1 Choose
the correct or the best alternative in the following: (2
10)
a. An instrument gives
maximum deflection for any amount of quantity passed
through
it. Which of the following are present?
(A)
Deflection and controlling force.
(B) Deflection and damping force.
(C) Damping and controlling force.
(D) Damping, controlling and deflecting force.
b. To measure 2 volts,
if one selects 0-100 volt range voltmeter which is accurate
within
1%.The error in
his/her measurement may be up to
________.
(A)
0.02 (B)
1%
(C) 2% (D)
50%
c.
The bridge used for the measurement of dielectric loss of capacitance is
__________.
(A)
(C) Hay bridge (D) Schering bridge
d. The
sensitivity of a Wheatstone bridge depends upon ______________.
(A) galvanometer current sensitivity
(B) galvanometer resistance
(C) bridge supply voltage
(D) All of the above.
e.
The
reading of the voltmeter connected in the circuit given in Fig.1 would be
nearest to ___________.
(A) 0 V
(B) 50 V
(C)
75 V
(D) 250 V
f. The
inductance of the coil using Q- meter can be calculated by the expression
(A) 
(B) 
(C) 
(D) 
g. A double beam oscilloscope has
___________.
(A)
two screens
(B)
two electron guns
(C)
two
different phosphor coatings
(D)
two horizontal deflection plates
h. A bolometer is used for measurement of __________.
(A)
Transmission
loss (B) High voltages
(C) Micro-wave power (D) VSWR
i. In
a direct magnetic tape recording
system, the reproducing head and amplifier
characterises are
(A)
–
6 dB/octave ,+ 6 dB /octave
(B)
–
6 dB/octave , +20dB / decade
(C)
+6 dB/octave , – 6dB / octave
(D)
–
20 dB/ decade , +20 dB /decade
j. Radiation
pyrometers are used in the temperature range of ________.
(A) 0-500º C (B)
500 - 1000º C
(C)
– 250 -500º C (D)
1200 - 2500º C
Q.2 a. What are ‘systematic errors’
in electric and electronic measuring instruments? Discuss these errors giving suitable examples. (8)
b. Current
was measured during a test as 30.4 A, flowing in a resistor of 0.105Ω. It was discovered later that the
ammeter reading was low by 1.2 percent and the
marked resistance was high by 0.3 percent. Find the
true power as a percentage of
the
power that was originally calculated. (8)
Q.3 a. Explain the principle of
working of a Kelvin’s
b. A 4 terminal
resistor of approximately 50 μΩ resistance was measured by means of a
Kelvin bridge having the following exponent resistances:
Standard resister = 100.03 μΩ
Inner ratio arms = 100.31 Ω and 200 Ω
Outer ratio arms = 100.24 Ω and 200 Ω
Resistance of link connecting standard and the
unknown resistance = 700 μΩ
calculated the unknown
resistance to the nearest 0.01 μΩ. (8)
Q.4 a. How large current is
measured using a thermocouple? (8)
b. Calculate the value of the
multiplier resistor for a 10 V rms range on the voltmeter shown in Fig.2. (8)
Q.5 a. Explain
with the help of a neat circuit diagram, the working of duel slope DVM. (8)
b. Explain with the help of a neat diagram, the
working of a digital frequency meter. (8)
Q.6 a. Explain the principle of operation of a storage
oscilloscope and a few applications of the same. (8)
b. list
the various controls on the front panel of the pulse generator. Mention their
uses. (8)
Q.7
Write
short note on the following:
(a) Harmonic distortion analyzer.
(b) Unbalanced 2)
Q.8 a.
List
specifications that should be considered while selecting a recording
instrument. (8)
b. If the frequency
of a signal to be recorded with a slip- chart recorder is 20 Hz, what must be
the chart speed used to record one complete cycle on 5 mm of recording paper. (8)
Q.9 a. Discuss
the merits and limitations of RTDS. (8)
b. Explain with a neat diagram the working of a
single DAS and give an example. (8)