Top 250+ Solved Testing and Commissioning of Electrical Equipment’s MCQ Questions Answer
Q. Why is an isolator installed?
a. To isolate one portion of the circuit from another
b. As an substitute for the circuit breaker
c. It used on either sides of the circuit breaker
d. Both (a) and (c)
Q. What is the cut off current in the fuse?
a. Maximum value actually reache(D)
b. Rms value actually reache(D)
Q. Which circuit breaker is preferred to be installed in extra high voltage ACsystem?
a. Bulk oil type circuit breaker
b. Air blast circuit breaker
c. SF6 circuit breaker
d. Vacuum circuit breaker
Q. A three phase circuit breaker is rated 2000 MVA, 33 kV. What will be its makingcurrent?
a. 35 kA
b. 49 kA
c. 70 kA
d. 89 kA
Q. Which among these tests are performed to check the nation or internationalstandards?
a. Type test.
b. Production tests.
c. Site checks.
d. All of the above.
Q. What is switchgear?
a. An apparatus used for switching, controlling and protecting the electrical circuits and equipments.
b. It detects the faults only.
c. It corrects the faults only.
d. All of the above.
Q. What is / are the main disadvantage / s of using oil as the quenching medium in the circuit breakers?
a. Need periodical replacement.
b. Risk of formation of explosive mixture with air.
c. Possibility of causing fire hazards.
d. All of the above.
Q. Which of the following circuit breakers has the lowest operating voltage?
a. SF6 circuit breaker
b. Air break
c. Air blast
d. Minimum oil circuit breaker
Q. The most efficient torque producing actuating structure for the induction typerelays is
a. Shaded pole structure
b. Watt hour meter structure
c. Induction cup structure
d. Single induction loop structure
Q. Plug setting of a electromagnetic relay can be altered by varying
a. Number of ampere turns
b. Air gap of magnetic path
c. Adjustable back stop
d. None of these
Q. Which material is used for the manufacture of bus bars?
a. Aluminium rods.
b. Copper rods.
c. Any conducting material.
d. Made of silver.
Q. Which device sends the information to the circuit breaker to interrupt the circuitin case of fault?
a. Switch
b. Relay
c. Circuit breaker itself does this function.
d. Fuse.
Q. When does the circuit breaker operate in the line?
a. When power is to be supplie(D)
b. When the line is to be teste(D)
c. Whenever the fault occurs in the line.
d. Whenever the switch and the relay has to be operate(D)
Q. What is the primary principle of a fuse?
a. Open the circuit.
b. Protect the appliance.
c. Protect the line.
d. Prevent excess current from flowing into the line.