Specifications

68
To fix the brush arm positions, commutator ring diagram is used, as shown in Fig. 5.5.
Fig. 5.4 - Main winding diagram
Fig. 5.5 - Commutator ring diagram
Now, transfer the brush arms to the main winding diagram. Tap out two leads and mark A
for positive brush arm and AA for negative brush arms. These two leads now indicate the
armature terminals of a dc machine.
5.4 DOUBLE LAYER SIMPLEX WAVE WINDING DIAGRAM
Problem 1 : 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.
Solution : Slots per pole =
= 3; Number of coils, C = number of commutator segments = 6
Number of coil sides = 2C = 12; Therefore, coil sides per slot = = 2; The back pitch,
(odd integer); The winding pitch,
(even integer); Here m = 1 for simplex wave winding. The front pitch, Y
f
= Y – Y
b
=10 –5 = 5
(odd integer)
1 2 3 4 5 6 7 8
9
10 11 12
N S N S
1
3 5 7 9 11 13 15
17 19 21 23
2
46810121416
18 20 22 24
2
46
2119 23
223
+ - +- + - +-
A
AA
+ - +
+ - +
1
5
9
13
17
21
812
16
20 24
4
1
-
3
7
11
15
19
23
10 14
18
22 2
6
3
-
12
6
2 C
P
12
2
Y
b
= + K = + K = 6 –1 = 5
2 C+12m
P
2
12
2
Y = = = 10