Instrument Transformers - MCQs with answers
Q1. Current transformers and potential transformers are used to increase the ranges ofA. Ac ammeter and ac voltmeter respectively
B. Ac ammeter and dc voltmeter respectively
C. Dc ammeter and dc voltmeter respectively
D. Dc ammeter and ac voltmeter respectively
View Answer / Hide AnswerANSWER: A. Ac ammeter and ac voltmeter respectively
Q2. For the measurement of energy and power it is essential to knowA. Only the transformation ratio
B. Phase angle between the primary and secondary currents
C. Both (a) and (b)
D. None of these
View Answer / Hide AnswerANSWER: C. Both (a) and (b)
Q3. The transformer ratio of the transformer depends upon theA. Exciting current
B. Secondary current
C. Power factor of secondary circuit
D. All of these
View Answer / Hide AnswerQ4. Primary current in a current transformer is determined byA. The load on the system
B. The load on its own secondary
C. The load on its own primary
D. All of these
View Answer / Hide AnswerANSWER: A. The load on the system
Q5. The potential transformers are used to measure large voltage usingA. High range voltmeter
B. Low range voltmeter
C. High range ammeter
D. Low range ammeter
View Answer / Hide AnswerANSWER: B. Low range voltmeter
Q6. If an instrument transformer is used to extend the ranges of AC instrument, then its reading will depend onA. R
B. L
C. C
D. None of these
View Answer / Hide AnswerQ7. The nominal ratio for a current transformer is given byA. rated primary winding current / rated secondary winding current
B. no. of turns in the primary winding / no. of turns in the secondary winding
C. no. of turns in the secondary winding / no. of turns in the primary winding
D. rated secondary winding current / rated primary winding current
View Answer / Hide AnswerANSWER: A. rated primary winding current / rated secondary winding current
Q8. The resistances of potential transformer winding is minimized by usingA. Thick conductors and small length of turns
B. Thin conductors and small length of turns
C. Thin conductors and large length of turns
D. Thick conductors and large length of turns
View Answer / Hide AnswerANSWER: A. Thick conductors and small length of turns
Q9. In potential transformer, with increase in frequency the phase angleA. Increases
B. Decreases
C. Remains same
D. None of these
Answer: A
View Answer / Hide AnswerQ10. Under normal operating condition, the excitation current of current transformer and potential transformerA. Both varies over a wide range
B. Varies over a wide range, remains constant
C. Remains constant, varies over a wide range
D. Both remains constant
View Answer / Hide AnswerANSWER: B. Varies over a wide range, remains constant