I50 POWER DISTRIBUTION FOR ELECTRIC RAILROADS. 
   
    
   
   
    
   
  
  
rangement. ‘The principal differences are to be found in 
the armature windings. ‘T'wo phase dynamos and motors 
customarily have two separate windings on the armature, 
displaced 9o degs. with reference to their spacing be- 
  
  
  
FI1G. S6. 
tween consecutive poles. This kind of winding with its 
overlapping coils is admirably shown in the Stanley two 
phase machine shown in Fig. 78. ‘Three phase generators 
are similarly arranged except that there are three sets of 
coils usually spaced 6o degs. apart, one set being reversed