High Voltage Engineering Test Questions - Set 6

1)   The resin bonded paper bushings are designed to operate at a maximum radial stress of

a. 5 kV/cm
b. 10 kV/cm
c. 15 kV/cm
d. 20 kV/cm
Answer  Explanation 

ANSWER: 20 kV/cm

Explanation:
No explanation is available for this question!


2)   Resins and varnishes are commonly used in

a. Generators and motors
b. Cables
c. Transformers
d. Circuit breakers
Answer  Explanation 

ANSWER: Generators and motors

Explanation:
No explanation is available for this question!


3)   The commonly used materials for HV insulation is

a. Paper-oil insulation
b. Polyester resin
c. Ceramic
d. PVC
Answer  Explanation 

ANSWER: Paper-oil insulation

Explanation:
No explanation is available for this question!


4)   The disadvantages of resonant transformers is

a. Pure sine wave output
b. No high power arcing
c. No repeated flashovers
d. Additional variable chokes
Answer  Explanation 

ANSWER: Additional variable chokes

Explanation:
No explanation is available for this question!


5)   In a series RLC circuit, the wave front and wave tail times are controlled by changing the value

a. R only
b. R and L simultaneously
c. R and C simultaneously
d. L and C simultaneously
Answer  Explanation 

ANSWER: R and L simultaneously

Explanation:
No explanation is available for this question!


6)   In a multistage impulse generator, for producing very high voltages, a bank of capacitors is

a. Charged in parallel and then discharged in series
b. Charged in series and then discharged in parallel
c. Charged in parallel and then discharged in parallel only
d. Charged in series and then discharged in series only
Answer  Explanation 

ANSWER: Charged in parallel and then discharged in series

Explanation:
No explanation is available for this question!


7)   For producing large values of impulse currents, a number of capacitors are charged in

a. Parallel and discharged in series
b. Parallel and discharged in parallel
c. Series and discharged in series
d. Series and discharged in parallel
Answer  Explanation 

ANSWER: Parallel and discharged in parallel

Explanation:
No explanation is available for this question!


8)   In large impulse generators, the spark gaps are generally

a. Sphere gaps
b. Hemispherical gaps
c. Square gaps
d. Either (a) or (b)
Answer  Explanation 

ANSWER: Either (a) or (b)

Explanation:
No explanation is available for this question!


9)   A Capacitance Voltage Transformer can be connected to a

a. High impedance device
b. Low impedance device
c. Relay coil
d. Only (b) and (c)
Answer  Explanation 

ANSWER: Only (b) and (c)

Explanation:
No explanation is available for this question!


10)   The attractive force between the electrodes of a parallel plate capacitor is

a. Directly proportional to the square of the applied voltage between plates
b. Directly proportional to the capacitance between the plates
c. Inversely proportional to the square of the separation between the plates
d. All of these
Answer  Explanation 

ANSWER: All of these

Explanation:
No explanation is available for this question!


11)   The series capacitor peak voltmeter is suitable for

a. Positive half cycle
b. Negative half cycle
c. Sinusoidal waveform
d. All of these
Answer  Explanation 

ANSWER: All of these

Explanation:
No explanation is available for this question!


12)   For voltage measurements, the gap which gives the highest accuracy is

a. Sphere gaps
b. Field gaps
c. Rod gaps
d. None of these
Answer  Explanation 

ANSWER: Sphere gaps

Explanation:
No explanation is available for this question!


13)   The sparkover voltage

a. Increases with humidity
b. decreases with the partial pressure of water vapour in air
c. Humidity effect decreases with the size of spheres
d. Humidity is minimum for uniform field gaps
Answer  Explanation 

ANSWER: Increases with humidity

Explanation:
No explanation is available for this question!


14)   The expected life at the rated stress can be determined by conducting long duration life tests at increased stress for

a. Less than 1 hr
b. 1 hr to about 1000 hr
c. More than 1000 hr
d. None of these
Answer  Explanation 

ANSWER: 1 hr to about 1000 hr

Explanation:
No explanation is available for this question!


15)   Impulse testing of transformers is done using

a. Full wave standard impulse
b. Chopped wave standard impulse
c. Half wave standard impulse
d. Only (a) and (b)
e. None of these
Answer  Explanation 

ANSWER: Only (a) and (b)

Explanation:
No explanation is available for this question!


16)   Failure during switching impulse tests are can be determined by

a. Visible in oscillograms
b. Loud noise produced
c. External flashovers
d. All of these
Answer  Explanation 

ANSWER: All of these

Explanation:
No explanation is available for this question!


17)   For operating power frequency voltages, a surge arrester has to be a

a. Conductor
b. Non-conductor
c. Semiconductor
d. None of these
Answer  Explanation 

ANSWER: Non-conductor

Explanation:
No explanation is available for this question!


18)   For the measurement of radio interference voltages, the detector circuit is provided with a measuring device to measure

a. Average value
b. Peak value
c. Quasi-peak value
d. All of these.
Answer  Explanation 

ANSWER: All of these.

Explanation:
No explanation is available for this question!