22 February 2011

Electrical Objective Questions:Transmission and Distribution (Set 4)

Electrical Objective Questions With Answers:

1) Stringing Charts are useful:
a) In design of the Transmission Towers
b) For Finding the SAG in the Conductors
c) In Design of Insulator String
d) To Find the distance between the Towers

2) Which is the topmost conductor in the HV transmission:
a) R-Phase Conductor
b) B-Phase Conductor
c) Y-Phase Conductor
d) Earth Conductor

3) The String Efficiency of a string of suspension insulators is dependent on:
a) Size of the Insulators
b) Number of Insulator discs in the String
c) Size of the Tower
d) None of the above

4) The Voltage across the various identical discs of a string of suspended insulators is different due to:
a) Because of different surface leakage current of each discs
b) Because of different series capacitance of each discs
c) Because of different Shunt capacitance to ground for each disc
d) Because of different series and shunt capacitance

5) String Efficiency of an Insulators can be increased by:
a) Increasing the number of insulator discs in the string
b) Decreasing the number of insulator discs in the string
c) correct grading of insulators of various capacitance
d) Changing the design orientation of the string to horizontal

6) If the frequency of transmission system is increased then the string efficiency:
a) Increase
b) Decreases
c) Remain unchanged
d) None of the above

7) The use of Gaurd Ring is to:
a) Equilises the voltage division between the insulator discs
b) Increases the voltage division between the insulator discs
c) Decreases the voltage distribution among the insulator discs
d) None of the above

8) The purpose of Gaurd Ring in the transmission system is to:
a) Reduce the earth capacitance of the lowest unit
b) Increases the earth capacitance of the lowest unit
c) Reduces the transmission losses
d) None of the above

Answers:

(1) b (2) d (3) b (4) c
(5) c (6) c (7) a (8)a


1 comment:

Anonymous said...

you should get more information about tunnel diode, this will help a lot in recognizing the problem.