A. Electrical considerations
B. Mechanical considerations
C. Thermal considerations
D. All of the above
Correct Answer: All of the above ✔
Last Updated: December 22, 2018
Related MCQs
- A current density of __________ is ilsed for large power transformers with forced circulation of oil or with water cooling coils?
- For 275 kV transformers, using cold rolled grain oriented steel, which of the following values of flux density may be used?
- D.C. windings are__________?
- The high voltage winding is usually which of the following type ?
- The flash point of transformer oil should be higher than__________?
- The usual values of maximum flux densities for distribution transformers using hot rolled silicon steel are__________?
- For large power transformers, self oil cooled type or air blast type which of the following values of current density may be used?
- A practical formula for determining the thickness of insulation between low voltage and high voltage windings is__________?
- The surge phenomenon is particularly important in case of__________?
- The insulation between windings and grounded core and the insulation between the windings of the same phase is called__________?
- __________ is the common method of applying brushes to the commntator?
- __________ brushes are fragile and cause excessive wear of commutator?
- The laminations of the armature of a D.C. machine are usually __________ thick?
- D.C. servomotors are used in__________?
- The cylindrical windings using circular conductors are used for current rating of__________?
- Which of the following in an application of D.C. motors?
- The stator of a D.C. machine comprises of__________?
- is usually used for brush rockers__________?
- Which of the following brushes can be used for high values of current density ?
- Which of the following problem arises in D.C. motors which are fed from thyristor bridge circuits ?
- In a D.C. machine the number of brush arms is _________ the number of poles?
- D.C. machines designed with a large value of air gap length have__________?
- In D.C. machines the usual limit of slot pitch is__________?
- The operation of a D.C. machine with large air gap lengths is comparatively__________?
- In D.C. machines, ir order to prevent excessive distortion of field form by the armature reaction, the field mmf must be made__________?
- In a D.C. machine, the value of peripheral speed should not, normally, exceed__________?
- The weight of copper of both armature and field windings decreases with __________ in number of poles?
- In a D.C. machine the current per brush arm should not be more than__________?
- In D.C. machines the width of the duct is usually__________?
- In D.C. machines, the ________ in field mmf results in increase in size and cost of machines?
- Which of the following methods may be adopted to reduce the effects of armature reaction ?
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- Power transformers have rating__________?
- __________are always double layer type?
- The winding where dummy coils are used is sometimes called__________?
- When the two coil sides forming a coil are spaced exactly one pole pitch apart they are said to be of__________?
- The distance between the starts of two consecutive coils measured in terms of coil sides is called__________?
- Dummy coil should not be used in__________?
- Power transformers should be designed to have maximum efficiency__________?
- Yokes with rectangular cross-section are used for__________?
- Which of the following methods is most accurate ?
- __________are used for construction of core of electromagnets?
- Tractive magnets are operated from__________?
- Which of the following is the commonly used type of electromagnets ?
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- electromagnets generally function as holding magnets ?
- By which of the following methods motor rating for variable load drives can be determined ?
- The value of exciting or magnetizing current depends upon which of the following factors ?
- By which of the following methods the temperature rise of windings and other parts may be determined ?
- Which of the following methods is used for air cooling of turbo-alternators ?