SRM University 2007 B.Tech Electronics and Communications Engineering Bank : Electronic Measurement

22. Explain the basic principle in staircase Ramp.
23. Draw the block diagram of a stair case Ramp kind.
24. State the advantages of a DVM over an analog meter.
25. State the advantages of a Dual slope over Ramp kind DVM.
26. What are the 2 basic DVM circuits used for measuring voltages?
27. State the advantages of an Aryton shunt ammeter over a multirange ammeter.
28. What are the requirements of a shunt?
29. What precautions are to be observed When using an ammeter?
30. Compare a multirange voltmeter with Aryton shunt voltmeter.
31. Which kind of meter movement is most widely used in an AC instruments for current and voltage measurements?
32. Differentiate ranging from series kind ohmmeter and a shunt kind ohmmeter.
33. Give the basic principle of a D’Arsonval movement.
34. What are the functions of counter weights in a PMMC movement?
35. What is damping in PMMC?
36. How the coil in PMMC is controlled?
37. Give the formula of the torque for a moving coil instrument.
38. What is swamping resistance?
39. Mention the applications of A/D converter.
40. Mention the applications of D/A converter.
41. What is Guarding technique?
42. Mention the applications of vector voltmeter.
PART – B

1 Explain the construction and working of a permanent magnet moving coil mechanism.
2 Explain the kinds of DC ammeters.
3 Briefly discuss the Aryton shunt and multi range ammeters.
4 Draw the schematic, including values, for an Aryton shunt for a meter movement having a full–scale deflection of one mA and an internal resistance of 500 ohm to cover the current ranges of 10,50,100 and 500 mA .
5 Explain briefly the multiplier resistor.
6 Explain the multirange voltmeter.
7 A basic d’ Arsonval movement with internal resistance 100 ohm,and full scale current one mA is to be converted in to a multirange dc voltmeter with voltage ranges of 0-10 v ,0-50 v, 0-250 v and 0-500 v.
8 Explain the series kind ohmmeter.
9 The series kind ohmmeter uses a 50 ohm basic movement requiring a full-scale deflection current of one mA . The internal battery voltage is three v.The desired scale marking for half scale deflection is 2000 ohm . compute (a) the value of R1 and R2.
(b) the maximum value of R2 to compensate for a 10 % drop
in battery voltage.
10 Explain the shunt kind ohmmeter.
11 The circuit of shunt kind ohmmeter uses a 10 mA basic d’ Arsonval movement with an internal resistance of five ohm . The battery voltage is three v . It is desired to replace the circuit by adding an improper resistor Rsh across the movement ,so that the instrument will indicate 0.5 ohm at the midpoint on its scale.

Earning:   Approval pending.