Top 150+ Solved Switch Gear and Protection MCQ Questions Answer
Q. The short circuit in any winding of the transformer is the result of
a. mechanical vibration
b. insulation failure
c. loose connection
d. impulse voltage
Q. relays are used for phase faults on long line.
a. Impedance
b. Reactance
c. Either of the above
d. None of the above
Q. For which of the following protection from negative sequencecurrents is provided?
a. Generators
b. Motors
c. Transmission line
d. Tr
Q. relay is preferred for phase fault on short transmission line.
a. Induction type
b. Reactance
c. Impedance
d. None of the above
Q. Distance relays are generally
a. split-phase relays
b. reactance relays
c. impedance relays
d. none of the above
Q. For which of the following ratings of the transformer differentialprotection is recommended ?
a. above 30 kVA.
b. equal to and above 5 MVA
c. equal to and above 25 MVA
d. none of the above
Q. A _______ is used to measure the stator % winding temperature ofthe generator.
a. thermocouple
b. pyrometer
c. resistance thermometer
d. thermometer
Q. The under voltage relay can be used for
a. generators
b. busbars
c. transformers
d. all of the above
Q. The relay with inverse time characteristic will operate within
a. 1.5 sec
b. 5 to 10 sec
c. 5 to 20 sec
d. 20 to 30 sec
Q. The single phasing relays are used for the protection of
a. single phase motors only
b. two phase motors only
c. two single phase motors running in parallel
d. three phase motors
Q. Which of the following devices will receive voltage surge firsttravelling on the transmission line ?
a. Lightning arresters
b. Relays
c. Step-down transformer
d. Switchgear
Q. Which of the following parameter can be neglected for a short line ?
a. Inductance
b. Capacitance
c. Resistance
d. Reactance
Q. Series reactors should have
a. low resistance
b. high resistance
c. low impedance
d. high impedance
Q. Which of the following circuit breakers has high reliability andminimum maintenance ?
a. Air blast circuit breakers
b. Circuit breaker with SF6 gas
c. Vacuum circuit breakers
d. Oil circuit breakers
Q. Arc in a circuit breaker is interrupted at
a. zero current
b. maximum current
c. minimum voltage
d. maximum voltage