The total losses in a well designed D.C. generator of 10 kW will be nearly______________?
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
D.C. Motors
Which of the following losses are significantly reduced by laminating the core of a D.C. generator ?
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
Which of the following loss in a D.C. generator is dissipated in the form of heat?
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
Which of the following loss in a D.C. generator is dissipated in the form of heat? Read More »
D.C. MotorsWhich of the following steps is likely to result in reduction of hysteresis loss in a D.C. generator ?
Which of the following steps is likely to result in reduction of hysteresis loss in a D.C. generator ?
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
In a manual shunt motor starter?
In a manual shunt motor starter?
A. over load relay is connected in series and no volt relay in parallel with the load
B. over load relay is connected in parallel and no volt relay in series with the load
C. over load relay and no volt relay are both connected in series with the load
D. over load relay and no volt relay are both connected in parallel with the load
In a manual shunt motor starter? Read More »
D.C. MotorsD.C. shunt motors are used for driving____________?
D.C. shunt motors are used for driving____________?
A. trains
B. cranes
C. hoists
D. machine tools
D.C. shunt motors are used for driving____________? Read More »
D.C. MotorsTorque developed by a D.C. motor depends upon_____________?
Torque developed by a D.C. motor depends upon_____________?
A. magnetic field
B. active length of the conductor
C. current flow through the conductors
D. number of conductors
E. radius of armature
F. all above factors
Torque developed by a D.C. motor depends upon_____________? Read More »
D.C. MotorsWhich of the following loss in a D.C. generator varies significantly with the load current ?
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
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 ?
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
In a D.C. generator all of the following could be the effects of iron losses except___________?
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