A shunt generator can self-excite

The e.m.f. generated by a shunt wound D.C. generator is E. Now while pole flux remains constant, if the speed of the generator is doubled, the e.m.f. generated will be

A

$$\frac{{\text{E}}}{2}$$

B

2E

C

Slightly less than E

D

E

If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens

A

This will make armature to take heavy current, possibly burning it

B

This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses

C

Nothing will happen to motor

D

Motor will come to stop

If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens

A

Nothing will happen to the motor

B

This will make armature to take heavy current, possibly burning it

C

This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses

D

Motor will run at very slow speed

A cumulatively compounded long shunt generator when operating as a motor would be

A

Cumulatively compounded long shunt

B

Differentially compounded long shunt

C

Cumulatively compounded short shunt

D

Differentially compounded short shunt

In a shunt generator the voltage build up is generally restricted by

A

speed limitation

B

armature heating

C

insulation restrictions

D

saturation of iron

The series field of a short-shunt D.C. generator is excited by

A

external current

B

armature current

C

shunt current

D

load current

The terminal voltage of a D.C. shunt generator drops on load because of all of the following reasons except

A

Armature reaction

B

Armature resistance drop

C

Field weakening due to armature reaction and armature

D

Commutation

A separately excited generator as compared to a self-excited generator

A

Is amenable to better voltage control

B

Is more stable

C

Has exciting current independent of load current

D

Has all above features

Which of the following components of a D.C, generator plays vital role for providing direct current of a D.C. generator?

A

Dummy coils

B

Commutator

C

Eye bolt

D

Equalizer rings

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

A shunt generator can self-excite

Related Questions