ALTERNATORS. 215 



CHARACTERISTIC ON NON-INDUCTIVE LOAD. 



Alternator No Type Periodicity 



Normal output . . . .amperes . . . .volts at .... revs, per min. 

 Resistance <jf armature (hot) .... ohms. 



The voltage readings must be corrected if the speed does 

 not remain constant. 



A curve obtained in this way on a 6 kw. 3-phase alternator 

 is shown in Fig. 100, at a constant excitation of 1-9 amps. 

 The curve is here drawn for the full working range of the 

 machine, which is rated to give a full-load current of 35 



100 



90 

 80 

 70 



. 60 

 w 



'o 



> 50 



40 

 30 

 20 

 10 

 







10 



30 



40 



20 



Amperes. 



FIG. 100. CHAKACTKBISTIC OK AN ALTKKNATOK 

 Excitation T9 amps. Speed 1,200 r.p.m. 



