302 



ARMATURE CONSTRUCTION 



the number of coils per phase is half the number of poles, i.e. 



o 



- = 4 coils per phase, and 4x3 = 12 coils in all. The number of 



a 



79 

 slots per pole per phase is . = 3 ; or 9 slots per pole. 



o X o 



From Table XIV., p. 203, we see that a half-coiled winding having 

 3 slots per pole per phase has triple coils ; or, from Table XV., a 



FIG. 362. Winding Block for Hand Winding. 



3-phase half-coiled winding having 9 slots per pole has triple coils. 

 Hence the coil must cover 3 slots on either side, as it is a triple 

 coil (see definition on p. 198). 



A view of a stator with a winding corresponding to the above 

 conditions is given in Fig. 361, and with such an armature we are 

 now dealing. 



The winding diagram for this armature is given in Fig. 244 on 

 p. 207. Taking coil No. 1, we have to wind from slot No. 10 to 

 slot No. 3, then taking in slots Nos. 11, 2, 12, and 1 in order. 



