ALTERNATING-CURRENT WINDING 189 



and Fig. 223 the most common for three-phase. So far as 

 divisibility of the armature and number of ranges in the winding 

 is concerned, the following table is of interest as setting forth the 

 properties of these fundamental windings : 



TABLE XII. 



PROPERTIES OF POLYPHASE WINDINGS. 



ERRATUM NOTE at p. 188. 



In fig. 223, Plate XII., the coils of the red phase should be displaced 

 through an angle of 60 or by one pole pitch, so that the outer periphery of 

 the diagram will appear exactly as in fig. 220. 



The winding of fig. 223 is intended to be identical with fig. 239, g, h, and k 

 (also figs. 244, 247, and 250) ; while fig. 229 is identical with fig. 239, G, H, 

 andK. 



All references in the text to fig. 223 apply to fig. 223 as corrected in this 

 manner. 



While on this matter of ranges, we shall formulate a few 

 general statements ; but first a reference to Fig. 230 is desirable. 



The sketches in Fig. 230 indicate a section through the arma- 

 ture core and the ends of the coils for various coil windings. 

 a and I show single-range windings. 



An inspection of any of the single-phase winding diagrams 

 already given will show that all single-phase windings are laid up 

 in one range, c and d show two-range windings. As has been 

 seen, both two-phase and some three-phase windings can be laid 

 up in this way. e, /, and g show three varieties of three-range 

 windings with the coils laid back to a greater or less extent. 



(1) For stationary alternator armatures, any of these varieties 

 can be employed. It is generally preferable to keep the coils well 

 back against the armature frame, and thus b } d, and e would be 

 more common. 



