ANNA UNIVERSITY QUESTION PAPERS
B.E. DEGREE EXAMINATION
IV Semester Instrumentation Engineering
Time : Three hours Maximum : 100 marks
Answer ALL questions.
PART A — (10 ´ 2 = 20 marks)
1. List the various types of Instrumentation components.
2. State the relative merits of pulleys and gears.
3. Bring out the difference between Gate valve and diaphram valve.
4. List out the advantages and disadvantages of pneumatic relays.
5. Define Power rating of a resistor.
6. List the types of fixed resistors.
7. Explain the function of LDR.
8. With neat diagram explain the principle of opto coupler.
9. Define the term ‘transformation ratio’ of a transformer.
10. Bring out the difference between relays and switches.
PART B — (5 ´ 16 = 80 marks)
11. (i) What are the types of gears? Explain how tight gearing without backlash can be achieved. (6)
(ii) Explain the principle and applications of Geneva mechanism. (6)
(iii) With neat diagram explain any two types of mechanical Indicating Mechanisms. (4)
12. (a) (i) With neat diagram explain the construction and working principle
of flapper nozzle. (6)
(ii) Discuss its response curve. (3)
(iii) What are the factors to be considered for selecting a control valve. (7)
(b) (i) With neat diagram explain the operation of pneumatic actuator
with and without positioner. (10)
(ii) Discuss the disadvantages of pneumatic actuator without positioner and also explain how it is eliminated in with positioner scheme. (6)
13. (a) With neat diagram explain the construction, working principle and application of a magnetic amplifier. (6 + 8 + 2)
(b) (i) Explain the construction of a variable reluctance stepper motor. (4)
(ii) Derive the torque equation of the stepper motor. (8)
(iii) Explain the application of stepper motor in open loop mode. (4)
14. (a) (i) Explain the construction and characteristics of thermistor. (6)
(ii) Explain the application of thermistor in
(1) Level measurement.
(2) Temperature Compensation. (10)
(b) (i) With neat diagram explain the construction and working principle of SCR. (10)
(ii) Explain how SCR is used in power control application. (6)
15. (a) (i) Explain the construction, working principle and application of PIN
(ii) Bring out the difference between Dispersion and Reflection prism.
(iii) Explain the working of LED. (5)
(b) (i) Explain the term grating and discuss its application. (8)
(ii) Write short notes on resonators and reflectors. (8)