Page 161 - Electrician - TT (Volume 2)

ELECTRICIAN - CITS

Y – Y = 12.
B
F
Hence, back pitch Y = 7 and front pitch Y = 5 for retrogressive wave winding.
B
F
The winding sequence of conductors for retrogressive wave winding is shown in Fig 6.
Y = 7, Y = 5.
B
F
Fig 6

Winding Table

Coil Conductor Slot Commutator
segments
From To From To From To
1 1 8 1 4 I VII

2 13 6 7 3 VII VI
3 11 4 6 2 VI V
4 9 2 5 1 V IV
5 7 14 4 7 IV III
6 5 12 3 6 III II

7 3 10 2 5 II I

Development winding diagram for 14 conductors, 2 poles, 7 slots, 7 segments, simplex, double
layer wave winding
Development diagram with coil connection : Fig 7 shows the arrangement of coils in their respective slots and
their connection to the segments.
Development diagram with conductors : Fig 8 shows the arrangement of armature conductors in the slots and
the connection to commutator segments.

Fig 7 Fig 8

Ring diagram : The ring diagram of wave winding in the case of a 2-pole armature will appear similar to that of
lap winding, but the coil ends will be connected as shown in Fig 9.
Sequence diagram : This diagram (Fig 10) is mainly used to trace the current direction of the coil sides (conductors)
and, thereby, locate the brush position. Please note the brush is placed at a distance of 3 commutator segments
i.e. less than 180° geometrical (app.155°).

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CITS : Power - Electrician & Wireman - Lesson 86-92