Questions and answers for exam Preparation

MCQs

Total Questions : 377 | Page 37 of 38 pages

Question 361. In a separately excited generator supplying rated load the armature reaction.

is always present
is always absent
may be sometimes present
none of the above

Discuss Question

Answer: Option A. -> is always present
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 362. As a result of armature reaction, the reduction in the total mutual air gap flux in a D.C. generator is approximately______________?

40 percent
25 percent
10 percent
5 percent

Discuss Question

Answer: Option D. -> 5 percent
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 363. Shunt generators are most suited for stable parallel operation because of their______________?

rising voltage characteristics
identical voltage characteristics
drooping voltage characteristics
linear voltage characteristics

Discuss Question

Answer: Option C. -> drooping voltage characteristics
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 364. For both lap and wave windings, there are as many commutator bars as the number of_____________?

slots
armature conductors
winding elements
poles

Discuss Question

Answer: Option C. -> winding elements
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 365. If a self excited D.C. generator after being installed, fails to build up on its first trial run, the first thing to do is to______________?

reverse the field connections
increase the field resistance
increase the speed of primemover
check armature insulation resistance

Discuss Question

Answer: Option A. -> reverse the field connections
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 366. Which of the following generating machine will offer constant voltage on all loads?

Self-excited generator
Separately excited generator
Level compounded generator
All of the above

Discuss Question

Answer: Option C. -> Level compounded generator
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 367. Which of the following generators will be preferred if they are required to be run in parallel?

Shunt generators
Series generators
Compound generators
None of the above

Discuss Question

Answer: Option A. -> Shunt generators
NO EXPLANATION IS AVAILABLE FOR THIS QUESTION!

Question 368. 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_____________________?