238 



ARMATURE CONSTRUCTION 



per slot ; (3) these joints will be easier to make than in the original 

 wave winding, as the conductor is only half as large ; (4) the scheme 

 permits of a thoroughly distributed winding, which is better from 

 the standpoints of heat dissipation and low inductance, and it has 

 also a better appearance, being carried out with cylindrical barrel 

 end connections ; (5) the bars may all be shaped in the same form 

 to either the shape shown in sketch C or D in Fig. 277. 



FIG. 278. One Phase of Six-pole Parallel -connected Three-slot Wave Winding. 

 Three Slots per Pole per Phase ; two Conductors per Slot. 



It will, however, be necessary with this winding to insulate the 

 top conductor from the bottom one in the slot, as there will be a 

 pressure between these conductors at certain points amounting to 

 two-thirds of the voltage per phase. As this will, in this case, only 

 amount to 170 volts, it is not serious with a low-voltage winding, 

 and 1 mm. will be ample insulation between conductors. If the 

 open slot is retained, the bars could be shaped as in sketch 0, and 

 dropped in at the mouth of the slots. The shape in sketch D 

 only requires one bend per bar, and could be used either witli un 



