DIRECT-CURRENT MACHINERY 



193 



In compound-wound machines the shunt winding may be con- 

 nected across the armature terminals, Fig. 156, called short shunt, 

 or outside of the series winding, Fig. 157, caljed long shunt. The 

 characteristic curves are not affected to a great extent by the dif- 



FIG. 158. Series generator. 



ference in connection since with the short shunt the voltage across 

 the shunt winding is higher than with the long shunt by the re- 

 sistance drop in the series winding and the current in the series 

 winding is less by the amount supplied to the shunt winding. 



CO 



7 



(2), 



Internal Characteristic 

 External Characteristic 



Current I 

 FIG. 159. Voltage characteristics of a series generator. 



117. Series Generator. The series generator, Fig. 158, is 

 excited by a series winding carrying the load current and has no 

 shunt winding. 



Its voltage characteristics are shown in Fig. 159. At no load 



