ANNA UNIVERSITY COIMBATORE B.E./B.Tech. DEGREE EXAMINATION:DECEMBER 2009 REGULATION-2008 (THIRD SEMESTER TO EEE) 080280016-MEASUREMENTS AND INSTRUMENTION Time : 3 hours Maximum : 100 marks PART A — (20 * 2 = 40 marks) 1. Listmain functional elements used in mostof the measurement systems. 2. what is static sensitivity of an instrument? 3. Write the different types of systematic errors. 4. Differentiate between dispersion and deviation. 5. Write the different torques produced in PMMC instrument. 6. Write the causes of opening the secondary circuit of a current transformer when the primary winding winding is energized 7. State the blondel's theorem 8. When two wattmeter method is used for mearuement of power in three phase balanced circuit,comment upon the reading of the two wattmeter when the power factor is 0.3 lagging 9. State the advantages of DC potentiometers 10.list the application of wien's bridge. 11.How to minimize the electrostatic interference? 12.Write the applications of ratio transformer. 13.what is a magnetic tape? 14.List the main parts of cathode ray tube. 15.Write the characteristics of modern data loggers 16.what are the different seciconductor material used for construction of LED? 17.Mention the different type of strain guages. 18.Write the advantages of differential output transducers. 19.What are the symmetrial crystalline materials used to construct piezoelectric transducers? 20.What are the drawback in variable network type digital to analong converters? PART B — (5 * 12 = 60 marks) 21.Describe the functional elements of an instrument with a block diagram. 22.Explain the integrating type and staircase ramp type digital voltmeters with the block diagrams. 23.Illustrate the differentmethods used for determining the B-H curve 24.Explain theoperation of basic slide wire DC potentiometer with circuit diagram and also illustrate the procedure for standardization. 25.With the help of neat circuit diagram explain the produres to measure resistance and capacitance using transfomer ratio bridge 26.Describe the working principle of magnetic tape and magnetic disk 27.(a)Write the advantages of LED (b)Draw the circuit diagram of data logger and explain its basic operation. 28.(a)what are the important factor to be considered for transducer to be physically compatible with its intended applications? (b) Design a 4-bit weighted variable resistive type digital to analog converter.