186 ARMATURE CONSTRUCTION 



the winding shown in Fig. 227, which is the two-phase winding 

 corresponding to the single-phase winding of Fig. 212, as each 

 phase is identical therewith. 



It will not be difficult to see that, by dealing with the three- 

 phase winding of Fig. 223 in like manner, we obtain the winding 

 of Fig. 228. 



In both Figs. 227 and 228 every pole is subtended by one coil 



FIG. 227. Two-phase Whole-coiled Winding (one coil per phase per pole). 



of each phase, i.e. the number of coils per phase equals the number 

 of poles, and these two windings are both whole-coiled windings. 



Keverting again to the half-coiled three-phase windings of 

 Fig. 223, there is another way of grouping the coils of the several 

 phases with respect to one another, the winding still remaining 

 half coiled. This grouping is shown in Fig. 229, and it is strictly 

 a six-phase grouping, as will be seen in Fig. 225, G and H. 



An inspection of Fig. 229 will show that the winding consists 

 of three groups of coils each group consisting of three coils, one 

 of each phase. For instance, the first group comprises all the 

 conductors from IA to 2c (inclusive). The armature, when 



