Specifications

QUESTIONS

Part - A

Choose the Correct Answer (1 Mark)

1. The value of back pitch of a dc armature winding should be

A) a even integer B) an odd integer C) equal to one D) a prime number

2. When a dc machine is operating as a generator, to find the current direction in the armature

winding ________________ is used.

A) Fleming’s left hand rule B) Ohm’s law

C) Fleming’s right hand rule D) Kirchhoff’s law

3. The number of parallel paths offered by the lap winding of a dc machine is

A) equal to 2 B) equal to P C) equal to 2P D) equal to P/2

4. The number of brush arms for a duplex lap winding for a 4 pole dc machine is

A) equal to 1 B) equal to 2 C) equal to P D) equal to 2P

5. The number of parallel paths offered by the wave winding of a dc machine is

A) equal to 2 B) equal to P C) equal to 2P D) equal to P/2

Part - B

Answer the following questions in one or two words (1 Mark)

1. What should be the value of back pitch of a dc armature?

2. What rule is used to find the current direction in the armature winding of a dc generator?

3. What is the number of parallel paths offered by the lap winding of a dc machine?

4. What is the number of parallel paths offered by the wave winding of a dc machine?

5. What is the number of brush arms of a duplex lap winding for a 2 pole dc machine?

Part - C

Answer the following questions briefly (4 Marks)

1. Calculate the back, font and winding pitches for a 2 pole, 6 slot simplex lap connected dc

machine with commutator having 6 segments.

2. Calculate the back, font and winding pitches for a 4 pole, 12 slot duplex lap connected dc

machine.

3. Calculate the back, font and winding pitches for a 2 pole, 6 slot double layer simplex wave

connected dc machine with commutator having 12 segments.

4. Calculate the back, font and winding pitches for for a 4 pole, 13 slot double layer simplex

wave connected dc machine with 13 commutator segments.

Part - D

Answer the following questions in two page level (20 Marks)

1. Draw the winding diagram for a 2 pole, 6 slot simplex lap connected dc machine with

commutator having 6 segments. Indicate the position of brushes.

2. Develop a winding diagram for a 4 pole, 12 slot duplex lap connected dc machine. Indicate

the position of brushes.

3. Draw the winding diagram for a 2 pole, 6 slot double layer simplex wave connected dc

machine with commutator having 12 segments. Indicate the position of brushes.