Top 250+ Solved Testing and Commissioning of Electrical Equipment’s MCQ Questions Answer
Q. What is the main advantage of using a fuse?
a. Cheapest type of protection.
b. Inverse time current characteristics.
c. Current limiting effect under short circuit conditions.
d. All of above.
Q. On what basis is the selection of fuse done?
a. Steady loa(D)
b. Fluctuating loa(D)
c. Both (a) and (b)
d. None of these.
Q. In a HRC fuse what is the time between the cut off and the final current zerocalled?
a. Pre - arcing time.
b. Arcing time.
c. Total operating time.
d. None of these.
Q. Which material is used in the liquid type of fuse?
a. SF6
b. Distilled water
c. Carbon tetra chloride.
d. Mineral oil / transformer oil
Q. What is the advantage of HRC fuses over Rewirable fuses?
a. High speed operation
b. High rupturing capacity
c. No ageing effect.
d. All of the above.
Q. If the strands of the fusing wire are twisted, what happens to the fusing current?
a. Increases
b. Reduces.
c. No change/ remains same
d. Depends on the value of current, increases or decreases.
Q. The least expensive protection for over current in low-voltage system is
a. Rewirable fuse
b. Isolator
c. Circuit breaker
d. Air-break switch
Q. Purpose of backup protection is
a. To increase the speed
b. To increase a reach
c. To leave no blind spot
d. To guard against failure of primary
Q. We do not require any protection against prime mover failure in case of
a. Turbo generator sets
b. Hydro generator sets
c. Diesel engine driven alternators
d. Back pressure turbo generators
Q. For the protection of stator winding of an alternate against internal fault involvingground the relay used is a
a. Biased differential relay
b. Directional over-current relay
c. Plain impedance relay
d. Buchholz relay
Q. For the protection of a large squirrel cage induction motor against single phasenormally
a. An over-current relay is used
b. Differential relay is used
c. Directional relay is used
d. Negative sequence current sensitive relay is used