Testing and Commissioning of Electrical Equipments (2180901) MCQs

MCQs of Testing of Transformer, Plant and Equipment

Showing 31 to 40 out of 66 Questions
1 2 3 4 5 6
31.
What extra we get by conducting PI test?
(a) Value of insulation resistance
(b) the prediction regarding insulation life
(c) Insulation resistance at different temperature
(d) All of these
Answer:

Option (b)

32.
Which value of PI indicates Good Insulation Condition?
(a) > 5 MΩ
(b) > 10 MΩ
(c) 2 - 3
(d) 3 - 4
Answer:

Option (d)

33.
Polarization Index Test (PI Value Test) along with Insulation Resistance Test (IR Value Test) is conducted on HV electrical machine to determine.
(a) Dryness and Cleanliness of the insulation
(b) Service Condition & fitness of the insulation.
(c) information about Life of Insulation
(d) All of these
Answer:

Option (d)

34.
When do we need to measure PI of Power transformer?
(a) Manufacturing
(b) Installation
(c) Schedule & Unschedule Maintenance
(d) All of these
Answer:

Option (d)

35.
Which of the following ration of IR used to determine the value PI of Large Power Transformer?
(a) IR at 10 min to IR at 1 min
(b) IR at 60 sec to IR at 15 sec
(c) IR at 1 min to IR at 10 min
(d) IR at 15 sec to IR at 60 sec
Answer:

Option (a)

36.
What did we measure during the ratio test in a transformer?
(a) The no-load voltage ratio between the two windings of a transformer.
(b) The full-load voltage ratio between the two windings of a transformer.
(c) IR60 to IR15 measurement of a transformer
(d) number of turn of both the windings
Answer:

Option (a)

37.
Why do we need to measure turns ration of the transformer?
(a) to confirm order specifications
(b) to examine the inter-turn short circuit
(c) to verify all tap positions
(d) All of these
Answer:

Option (d)

38.
Which of the following is/are the method of turns ratio measurement?
(a) Standard Transformer method
(b) Ratio Meter
(c) Direct Measurement
(d) All of these
Answer:

Option (d)

39.
What should be the reason for General overheating (temperature rise above normal) in the transformer?
(a) overloading
(b) Low level of oil
(c) Troubles in ventilation
(d) All of these
Answer:

Option (d)

40.
What should be the reason for low Secondary voltage in transformer?
(a) Wrong Tapping selected
(b) Low transformer oil
(c) Low winding impedance
(d) All of these
Answer:

Option (a)

Showing 31 to 40 out of 66 Questions
1 2 3 4 5 6