D.C. Generators Archives - Page 10 of 13 -

D.C. generators are connected to the busbars or disconnected from them only under the floating condition________________?

D.C. generators are connected to the busbars or disconnected from them only under the floating condition________________?

A. to avoid sudden loading of the primemover
B. to avoid mechanicaljerk to the shaft
C. to avoid burning of switch contacts
D. all above

D.C. generators are connected to the busbars or disconnected from them only under the floating condition________________? Read More »

D.C. Generators

Armature reaction of an unsaturated D.C. machine is_____________?

D.C. Generators / admin

Armature reaction of an unsaturated D.C. machine is_____________?

A. crossmagnetising
B. demagnetising
C. magnetising
D. none of above

Armature reaction of an unsaturated D.C. machine is_____________? Read More »

D.C. Generators

If brushes of a D.C. generator are moved in order to bring these brushes in magnetic neutral axis, there will be________________?

D.C. Generators / admin

If brushes of a D.C. generator are moved in order to bring these brushes in magnetic neutral axis, there will be________________?

A. demagnetisation only
B. cross magnetisation as well as mag¬netisation
C. crossmagnetisation as well as demagnetising
D. cross magnetisation only

If brushes of a D.C. generator are moved in order to bring these brushes in magnetic neutral axis, there will be________________? Read More »

D.C. Generators

In D.C. generators, the brushes on commutator remain in contact with conductors which_________________?

D.C. Generators / admin

In D.C. generators, the brushes on commutator remain in contact with conductors which_________________?

A. lie under south pole
B. lie under north pole
C. lie under interpolar region
D. are farthest from the poles

In D.C. generators, the brushes on commutator remain in contact with conductors which_________________? Read More »

D.C. Generators

The insulating material used between the commutator segments is normally_____________?

D.C. Generators / admin

The insulating material used between the commutator segments is normally_____________?

A. graphite
B. paper
C. mica
D. insulating varnish

The insulating material used between the commutator segments is normally_____________? Read More »

D.C. Generators

The material for commutator brushes is generally_______________?

D.C. Generators / admin

The material for commutator brushes is generally_______________?

A. mica
B. copper
C. cast iron
D. carbon

The material for commutator brushes is generally_______________? Read More »

D.C. Generators

In case of a 4-pole D.C. generator provided with a two layer lap winding with sixteen coils, the pole pitch will be__________________?

D.C. Generators / admin

In case of a 4-pole D.C. generator provided with a two layer lap winding with sixteen coils, the pole pitch will be__________________?

A. 4
B. 8
C. 16
D. 32

In case of a 4-pole D.C. generator provided with a two layer lap winding with sixteen coils, the pole pitch will be__________________? Read More »

D.C. Generators

If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by______________?

D.C. Generators / admin

If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by______________?

A. Blv
B. Blv2
C. Bl2v
D. Bl2v2

If B is the flux density, I the length of conductor and v the velocity of conductor, then induced e.m.f. is given by______________? Read More »

D.C. Generators

If a D.C. generator fails to build up the probable cause could not be_____________?

D.C. Generators / admin

If a D.C. generator fails to build up the probable cause could not be_____________?

A. imperfect brush contact
B. field resistance less than the critical resistance
C. no residual magnetism in the generator
D. faulty shunt connections tending to reduce the residual magnetism

If a D.C. generator fails to build up the probable cause could not be_____________? Read More »

D.C. Generators

Brushes of D.C. machines are made of_________?

D.C. Generators / admin

Brushes of D.C. machines are made of_________?

A. carbon
B. soft copper
C. hard copper
D. all of above

Brushes of D.C. machines are made of_________? Read More »

D.C. Generators