Top 80+ Solved Transformers MCQ Questions Answer
Q. Which of the following protection is normally not provided on small distributiontransformers ?
a. Overfluxing protection
b. Buchholz relay
c. Overcurrent protection
d. All of the above
Q. Which of the following acts as a protection against high voltage surges due to lightning and switching ?
a. Horn gaps
b. Thermal overload relays
c. Breather
d. Conservator
Q. The efficiency of two identical transformers under load conditions can bedetermined by
a. short-circuit test
b. back-to-back test
c. open circuit test
d. any of the above
Q. Which of the following insulating materials can withstand the highest temperaturesafely ?
a. Cellulose
b. Asbestos
c. Mica
d. Glass fibre
Q. Which of the following parts of a transformer is visible from outside ?
a. Bushings
b. Core
c. Primary winding
d. Secondary winding
Q. Which of the following loss in a transformer is zero even at full load ?
a. Core loss
b. Friction loss
c. Eddy current loss
d. Hysteresis loss
Q. Which of the following is the most likely source of harmonics in a transformer ?
a. poor insulation
b. Overload
c. loose connections
d. Core saturation
Q. If a transformer is continuously operated the maximum temperature rise will occurin
a. core
b. windings
c. tank
d. any of the above
Q. The hum in a transformer is mainly attributed to
a. load changes
b. oil in the transformer
c. magnetostriction
d. mechanical vibrations
Q. The maximum load that a power transformer can carry is limited by its
a. temperature rise
b. dielectric strength of oil
c. voltage ratio
d. copper loss
Q. The efficiency of a transformer, under heavy loads, is comparatively low because
a. copper loss becomes high in proportion to the output
b. iron loss is increased considerably
c. voltage drop both in primary and secondary becomes large
d. secondary output is much less as compared to primary input
Q. An open-circuit test on a transformer is conducted primarily to measure
a. insulation resistance
b. copper loss
c. core loss
d. total loss
Q. A no-load test is performed on a transformer to determine
a. core loss
b. copper loss
c. efficiency
d. magnetising current and loss
Q. The voltage transformation ratio of a transformer is equal to the ratio of
a. primary turns to secondary turns
b. secondary current to primary current
c. secondary induced e.m.f. to primary induced e.m.f.
d. secondary terminal voltage to primary applied voltage