Search
.Management Sciences
Category: D.C. Generators
Satisfactory commutation of D.C. machines requires______________?
A. brushes should be of proper grade and size
B. brushes should smoothly run in the holders
C. smooth, concentric commutator properly undercut
D. all of the above
In case of D.C. machine winding, number of commutator segments is equal to______________?
A. number of armature coils
B. number of armature coil sides
C. number of armature conductors
D. number of armature turns
A D.C. welding generator has____________?
A. lap winding
B. wave moving
C. duplex winding
D. any of the above
Lap winding is composed of_____________?
A. any even number of conductors
B. any odd number of conductors
C. that even number which is exact multiple of poles + 2
D. that even number which is exact multiple of poles
Following D.C. generator will be in a position to build up without any residual magnetism in the poles______________?
A. series generator
B. shunt generator
C. compound generator
D. self-excited generator
The open circuit voltage of a compound generator is 250 V. At full load the terminal voltage____________?
A. will be less than 250 V
B. will always be 250 V
C. may be greater or less than 250 V
D. none of the above
The armature of D.C. generator is laminated to_______________?
A. reduce the bulk
B. provide the bulk
C. insulate the core
D. reduce eddy current loss
The essential condition for parallel operation of two D.C. generators is that they have ________________?
A. same kW rating
B. the same operation r.p.m.
C. the same drooping voltage characteristics
D. same percentage regulation
The terminal voltage of a series generator is 150 V when the load current is 5 A. If the load current is increased to 10 A, the terminal voltage will be____________?
A. 150 V
B. less than 150 V
C. greater than 150 V
D. none of the above
In over compounded generator, full load terminal voltage is______________?
A. almost zero
B. less than no load terminal voltage
C. more than no load terminal voltage
D. equal to no-load terminal voltage
Recent Comments