A. Providing laminations in armature core
B. Providing laminations in stator
C. Using non-magnetic material for frame
D. Using material of low hysteresis co-efficient for armature core material
Related Mcqs:
- The losses occurring in a D.C. generator are given below. Which loss is likely to have highest proportion at rated load of the generator ?
A. hysteresis loss
B. field copper loss
C. armature copper loss
D. eddy current loss - The hysteresis loss in a D.C. machine least depends on____________?
A. Frequency of magnetic reversals
B. Maximum value of flux density
C. Volume and grade of iron
D. Rate of flow of ventilating air - Which of the following loss in a D.C. generator varies significantly with the load current ?
A. Field copper loss
B. Windage loss
C. Armature copper loss
D. None of the above - Which of the following loss in a D.C. generator is dissipated in the form of heat?
A. Mechanical loss
B. Core loss
C. Copper loss
D. All of the above - In a D.C. generator all of the following could be the effects of iron losses except___________?
A. Loss of efficiency
B. Excessive heating of core
C. Increase in terminal voltage
D. Rise in temperature of ventilating air - Which of the following losses are significantly reduced by laminating the core of a D.C. generator ?
A. Hysteresis losses
B. Eddy current losses
C. Copper losses
D. Windage losses - The total losses in a well designed D.C. generator of 10 kW will be nearly______________?
A. 100 W
B. 500 W
C. 1000 W
D. 1500 W - The condition for maximum efficiency for a D.C. generator is______________?
A. eddy current losses = stray losses
B. hysteresis losses = eddy current losses
C. copper losses = 0
D. variable losses = constant losses - In a D.C. generator, the iron losses mainly take place in___________/
A. yoke
B. commutator
C. armature conductors
D. armature rotor - Sparking at the commutator of a D.C. motor may result in____________?
A. damage to commutator segments
B. damage to commutator insulation
C. increased power consumption
D. all of the above
