THE SINGLE-PHASE SERIES MOTOR. 309 



poles as indicated by the dots and crosses in Fig. 264 and by the 

 arrows in Fig. 265. In the single-phase series motor this neutral- 

 izing winding may be connected in series with the armature 

 (forced compensation), or it may be short-circuited by connect- 

 ing the terminals t and /', Fig. 265, together (transformer 

 compensation). 



Figures 266 and 267 show the field member of a four-pole 

 single-phase series motor of the Westinghouse Electric and 



Fig. 267. 



Manufacturing Company. The field windings and the neutraliz- 

 ing windings are both shown in position in Fig. 266, and in Fig. 

 267 the field coils are removed so as to expose the neutralizing 

 windings to view. The neutralizing windings are placed in slots 

 in the laminated pole pieces, and the portions aaaa and bbbb, 

 Fig. 265, of the neutralized windings are bent back in Figs. 266 

 and 267 to make room for the ends of the field coils. 



143. Prevention of sparking in the single-phase series motor. 

 A number of undesirable effects are included under the general 

 term of sparking, as follows : (a) The effects that are presented 



