A. to increase the series flux
B. to increase the generated e.m.f.
C. to reduce the combined effect of ar-mature reaction of both the machines
D. so that the two identical machines will pass approximately equal cur¬rents to the load
Related Mcqs:
- When two D.C. series generators are running in parallel, an equilizer bar is used________________?
A. to increase the speed and hence generated e.m.f.
B. to increase the series flux
C. so that two similar machines will pass approximately equal currents to the load
D. to reduce the combined effect of ar-mature reaction of both machines - Two generators are running in parallel. One of the generators may run as motor for which of the following reasons ?
A. The direction of that generator is reversed
B. The speed of that generator is increased
C. The field of that generator is weakened
D. That generator takes large share of loads - Two D.C. shunt generators, each with armature resistance of 0.02 ohm and field resistance of 50 ohm run in parallel and supply a total current of 1000 amperes to the load circuit. If their e.m.fs. are 270 V and 265 V, their bus bar voltage will be_____________________?
A. 270 V
B. 267.5 V
C. 265 V
D. 257.4 V - Equilizer rings are required in case armature is_______________?
A. wave wound
B. lap wound
C. delta wound
D. duplex wound - For the parallel operation of two or more D.C. compound generators, we should ensure that_______________?
A. voltage of the incoming generator should be same as that of bus bar
B. polarity of incoming generator should be same as that of bus bar
C. all the series fields should be run in parallel by means of equilizer connection
D. series fields of all generators should be either on positive side or negative side of the armature
E. all conditions mentioned above should be satisfied - Which of the following generators will be preferred if they are required to be run in parallel?
A. Shunt generators
B. Series generators
C. Compound generators
D. None of the above - Shunt generators are most suited for stable parallel operation because of their______________?
A. rising voltage characteristics
B. identical voltage characteristics
C. drooping voltage characteristics
D. linear voltage characteristics - The main factor which leads to unstable parallel operation of flat and over compounded generators is_____________?
A. their rising voltage characteristics
B. unequal number of turns in their series field windings
C. unequal speed regulation of their primemovers
D. unequal series field resistances - 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 - In D.C. generators, current to the external circuit from armature is given through_____________?
A. commutator
B. solid connection
C. slip rings
D. none of above
