Design of DC Machines Interview Question Answer - 10

136	Whether the current density is uniform during commutation?
	Delay or retard commutation The current density is excessive during trailing edge of brush whereas it is small at the leading edge of brush.

Design of DC Machines Interview Question Answer - 9

Important Questions on Design of DC Machines

In this post, some of important questions of Design of DC Machines are given. It includes voltage between commutator segments, selecting number of slots, number of armature slots, pulsating losses, current density in the armature conductor, factor affecting slot size, wide open slot, depth of slot, slot depth to width, resistance offered during commutation, linear commutation and delay time.

Design of DC Machines Interview Question Answer - 8

Important Questions of Design of DC Machines

In this post, some of the important questions of design of dc machines are given. It includes commutation, methods of reduction of armature reactions, function of compensating winding, interpoles, location of interpoles, polarity of interpoles, chamfering of pole faces and limitation of wave winding.

Design of DC Machines Interview Question Answer - 7

91	What should be width of radial ventilating ducts for DC machine?
	10 mm

Design of DC Machines Interview Question Answer - 6

76	Describe the effect of poles on the inactive conductor of the armature.
	Number of poles – Inactive conductor The pole pitch of the armature is inversely proportional to number of poles for the constant diameter of machine.

Design of DC Machines Interview Question Answer - 5

61	Comment : The conductor area is directly proportional to square of armature diameter.
	Conductor area – Armature diameter Let we assume that conductor area is directly proportional to square of armature diameter.

Design of DC Machines Interview Question Answer - 4

46	Describe the advantages of laminated structure of DC machine.
	Advantages of laminated structure To reduce eddy current loss To reduce time constant of winding

Design of DC Machines Interview Question Answer - 3

31	State the application of hard carbon brushes.
	The hard carbon brushes are used in fractional HP slow speed machines.

Design of DC Machines Interview Question Answer - 2

16	Which type of conductor used for inter pole winding?
	Round or square for small rating machine and copper strip for large rating machine

Design of DC Machines Interview Question Answer - 1

1	State the applications of DC machines.
	Applications of DC machines Air crafts Ships