THE ROTARY CONVERTER. 



335 



will, on the whole, tend to assist the impressed voltage 

 and oppose the back voltage. Under these conditions the 

 current will lead the terminal voltage in phase. This 

 action has been explained more fully in the discussion of 

 synchronous motors. 



EXPERIMENT XLIX. DETERMINATION OF EFFECT OF 

 VARIATION OF EXCITATION UPON EATIO OF TRANSFORMA- 

 TION OF A ROTARY CONVERTER. (2) CONVERTER DRIVEN 

 FROM ALTERNATING SIDE. 



DIAGRAM OF CONNECTIONS. 

 Same as for Experiment XLVIII., Fig. 165. 



Instructions. Connect up and start the machine as 

 described in the case of Experiment XLVIII., page 330. 



With the direct current circuit open, vary the excita- 

 tion, and for each value of the exciting current take 

 readings of both direct and alternating voltages and the 



3 -4 -5 -6 -7 -8 



Amperes, excitation. 



FIG. 167. ROTARY CONVERTER DRIVEN FROM A.C. SIDE. 

 (TRVES OF CURRENT AND POWER FACTOR. 

 Curves I. no load. 

 Curves II. 4 amperes load. 

 Primary volts = 58. 



