Electrical Engineering Lab Viva Questions:
Experiment of DC Machine:
1. What Are The Difference between electrical motor and generator?
2. What is the Need for starters?
3. Which is the basic protective device In Any circuit?
4. How to find out the fuse rating?
5. Name the different Kinds of DC starter?
6. What is the role of Holding Coil in a DC choke?
7. Why is the armature of dc motor rheostat Kept at maximum resistance position?
8. Write the e.m.f. equation of DC machine
.9. Write the equation of DC motor torque.
10. Name the share of dc machine.
11. What is the use of commutator and brushes?
12. Draw the Electrical Characteristics and N / Ia Characteristics of a DC shunt motor.
13. How are ammeters and voltmeters the Connected In Any circuit?
14. What are the methods of speed control of dc motors?
15. What is back emf? Give icts significance.
16. What is the Difference between self-excited and separately excited machine?
17. Name the Kinds of self excited dc machine.
18. What are the Losses in dc machine?
19. How is the eddy current loss minimized in dc machine?
20. Why is armature resistance less Than field resistance of dc shunt machine?
21. Why is More Than armature resistance of dc series field resistance machine?
22. Why Should not dc series motor started at no load?
23. What is L, F, A, N in dc starters?
24. Given oven terminals without indication. How will you manage to find the field andarmature terminals of i) dc shunt machine ii) dc series machine.
Experiment of AC Machine:1. What is the principle of a turn?
2. What are the Kinds of change?
3. What are the applications of transform?
4. Why is the capacity of a specified transform fired, return not Have KVA and KW?
5. What is the maximum efficiency of Requirement for a turn?
6. Why is the efficiency of a transform Higher Than That of motors?
7. What is the purpose of OC and SC tests?
8. Why is the laminated core of a turn?
9. What is Meant by Regulation?
10. Define the term transformation ratio?
11. What are the components of no load current?
12. How are the Parties to the main parameters to the HV or LV side? Explain with example year.
13. What is Meant by power factor? Explain.
14. What Will Happen if dc supply is connected to turn? '
15. What are the shares of turn?
16. Why are not self starting synchronous motors? What are the methods of starting?
17. Why are single phase induction motors not self starting? Classify Them According To the starting methods.
18. Why is doubly excited synchronous motor as Parties to the main machine?
19. What is slip of induction motor year?
20. Why is always the induction motor running with less Than the speed of rotatingmagnetic field?
21. What are the Kinds of three phase induction motors?
22. Why is Three phase induction motor as Parties to the short-circuited rotating hand with transforming secondary?
23. What is the use of end rings in squirrel cage induction motor?
24. What is mutual inductance?
25. What is the principle of motor, generator and transform?
26. How will you reverse the direction of the rotation of the i) dc motor ii) ac motor?
27. What is M, L, C, and V in wattmeter?
28. What is E and C in autotransformer?
29. What are the Disadvantages of low power factor?
30. What are the methods of speed control of ac motors?
31. Given transformers A and B with details FOLLOWING:A: η = 96% & reg: 5.8%B: η = 94% & reg: 5.2%Which currency will you select? Justify your answer.
32. What do you mean by hunting?
33. What is Meant by magnetizing current and active (working) component of currentwith respect to transform?
34. Give the relationship Between line and phase values ofi) star connected networkii) delta connected network.
35. When the squirrel cage machine to be loaded Canon icts fullest capacity? i) Starconnection of stator ii) delta connection of stator.
36. How Can the eddy current and hysteresis loss of Be Any machine minimized?
37. What are the methods of electrical Braking?
38. Draw the torque-slip Characteristics of Three phase induction motor and explain.
39. State the Farraday's Law of Electromagnetic Induction?
40. Explain the right hand thumb rule.
41. Draw the open and short-circuit Characteristics Of An alternator.