A. from 2 to 5 years
B. 10 to 15 years
C. 25 to 30 years
D. 60 to 70 years
Related Mcqs:
- The usual spans with R.C.C. poles are_______________?
A. 40—50 meters
B. 60—100 meters
C. 80—100 meters
D. 300—500 meters - Which of the following relays is used on long transmission lines?
A. Impedance relay
B. Mho’s relay
C. Reactance relay
D. None of the above - In aluminium conductors, steel core is provided to____________?
A. compensate for skin effect
B. neutralise proximity effect
C. reduce line inductance
D. increase the tensile strength - jCorona usually occurs when the electrostatic stress in air around the conductor exceeds?
A. 6.6 kV (r.m.s. value)/cm
B. 11 kV (r.m.s. value)/cm
C. 22 kV (maximum value)/cm
D. 30 kV (maximum value)/cm - Constant voltage transmission entails the following disadvantage?
A. large conductor area is required for same power transmission
B. short-circuit current of the system is increased
C. either of the above
D. none of the above - The following system is not generally used?
A. 1-phase 3 wire
B. 1-phase 4 wire
C. 3-phase 3 wire
D. 3-phase 4 wire - Which of the following materials is not used for transmission and distribution of electrical power________________?
A. Copper
B. Aluminium
C. Steel
D. Tungsten - Which of the following D.C. distribution system is the simplest and lowest in first cost ?
A. Radial system
B. Ring system
C. Inter-connected system
D. None of the above - In transmission lines the cross-arms are made of________________?
A. copper
B. wood
C. R.C.C.
D. steel - Transmitted power remaining the same, if supply voltage of a D.C. 2-wire feeder is increased 100 percent, saving in copper is____________________?
A. 25 percent
B. 50 percent
C. 75 percent
D. 100 percent
