Top 150+ Solved Switch Gear and Protection MCQ Questions Answer
Q. Wave trap is used to trap waves of
a. power frequencies
b. higher frequencies entering generator or transformer units
c. either of the above
d. none of the above
Q. Ungrounded neutral transmission system is not recommendedbecause of system
a. insulation being overstressed due to over voltages
b. insulation overstress may lead to failure and subsequent phase to phase faults
c. being inadequately protected against ground fault
d. all of the above
Q. The reflection co-efficient at the open circuited end of a transmissionline.
a. zero
b. infinity
c. unity
d. none of the above
Q. For the protection of power station buildings against direct strokes the requirements are
a. interception
b. interception and conduction
c. interception, conduction and dissipation
d. interception, conduction, dissipation and reflection
Q. The line insulation is the insulation level of the station equipment.
a. less than
b. same as
c. more than
d. not directly related with
Q. The interaction between a transmission line and communication lineis minimized by
a. transposing transmission as well as communication lines
b. increasing the height of the trans-mission line tower
c. increasing the distance between the two lines
d. all of the above
Q. When a wave propagates on a transmission line, it suffers reflection several times at
a. tapping
b. load end
c. sending end
d. sending and other end
Q. Which of the following statements is incorrect?
a. Station batteries are used to operate relay only
b. The lightning arresters are basically surge diverters
c. An impedance relay has maximum fault current when fault occurs near the relay
d. A high speed relay has an operation of 1 to 2 cycles
Q. Discrimination between main and back up protection is provided bythe use of relays which are
a. fact
b. sensitive
c. slow
d. none of the above
Q. Induction cup relay is operated due to changes in
a. current
b. voltage
c. impedance
d. all of the above
Q. A.C. network analyser is used to solve problems of
a. load flow
b. load flow and short-circuit
c. load flow and stability
d. load flow, short-circuit and stability
Q. Short-circuit currents are due to
a. single phase to ground faults
b. phase to phase faults
c. two phase to ground faults
d. any of these
Q. To reduce short circuit fault currents are used.
a. reactors
b. resistors
c. capacitors
d. none of the above
Q. Bus coupler is very essential in arrangement
a. single bus
b. double bus, double breaker
c. main and transfer bus
d. all of the above
Q. For cost and safety, the outdoor substations are installed for voltagesabove
a. 11 kV
b. 33 kV
c. 60kV
d. 110kV