Helical coils can be used on___________________?

Related Mcqs:

1. Helical coils can be used on___________?

   A. low voltage side of high kVA transformers
   B. high frequency transformers
   C. high voltage side of small capacity transformers
   D. high voltage side of high kVA rating transformers

2. Spacers are provided between adjacent coils?

   A. to provide free passage to the cooling oil
   B. to insulate the coils from each other
   C. both A. and (b)
   D. none of the above

3. The efficiency of a transformer will be maximum when_____________?

   A. copper losses = hysteresis losses
   B. hysteresis losses = eddy current losses
   C. eddy current losses = copper losses
   D. copper losses = iron losses

4. The purpose of providing iron core in a step-up transformer is?

   A. to provide coupling between primary and secondary
   B. to increase the magnitude of mutual flux
   C. to decrease the magnitude of mag-netizing current
   D. to provide all above features

5. The noise resulting from vibrations of laminations set by magnetic forces, is termed as_________________?

   A. magnetostrication
   B. boo
   C. hum
   D. zoom

6. The leakage flux in a transformer depends upon______________?

   A. load current
   B. load current and voltage
   C. load current, voltage and frequency
   D. load current, voltage, frequency and power factor

7. If the supply frequency to the transformer is increased,”the iron loss will__________?

   A. not change
   B. decrease
   C. increase
   D. any of the above

8. An open-circuit test on a transformer is conducted primarily to measure______________?

   A. insulation resistance
   B. copper loss
   C. core loss
   D. total loss
   E. efficiency
   F. none of the above

9. The transformer lamination’s are insulated from each other by____________?

   A. mica strip
   B. thin coat of varnish
   C. paper
   D. any of the above

10. Which of the following protection is normally not provided on small distribution transformers ?

    A. Overfluxing protection
    B. Buchholz relay
    C. Overcurrent protection
    D. All of the above