THE ALTERNATOR. 5 



The revolving-armature type of alternator is generally used in 

 small electric lighting stations. Figure 5 shows an alternator of 

 this type manufactured by the Fort Wayne Electric Works. The 

 figure shows the small belt-driven exciter, and it shows, although 

 somewhat indistinctly, the rectifying commutator through which 



Fig. 7. Revolving-field alternator with direct-connected exciicr. 



a series field winding is connected in the main circuit of the ma- 

 chine as explained in Art. 2. 



Very large alternators are usually of the revolving-field type. 

 A small belt-driven machine of this type, built by the Allis- 



