THE REGULATION OF TRANSFORMERS 103 



'1 IK- diagram in Fig. 61 shows the construction which 

 sh.-uld he employed when the power factor of the circuit 

 >npplied l.y tin- secondary is less than unity, and the current 

 In-N behind the terminal pressure. In the case illustrated, 

 C /' represents the 

 secondary terminal ,5 



P iv .-MI iv of 100 volts. 

 1 he current lags behind 

 the pressure by 80. 

 Since cos 80 = 0,886, 

 tin- power factor of the 



i lit supplied from 

 thf secondary is 0,886 

 (0- = 0,886). The 

 vector C E indicates 

 the direction of the 

 secondary current, and 

 IS 30 behind C B, the 

 vector representing the 

 secondary terminal 



wore. In Figs. 59 

 and 60 the single vector 

 C B represented the 

 phase of the secondary 



ninal pressure and 

 also th-- phase of the 

 secondary current 

 which wa> in phase with 

 the pressure. C D of 

 ' '.I iv presents the 



n. th : per 



lag* = 63. Cos* - 



e drop of 30 volts at rated load, and is DO in phase 

 In-hind the vector < En piv^-ntin-4 tin- current. Tin- resistance 



represented, as in Fig. 60, by a vector .1 1>, which 

 nine direction as h vector C E repre- 



senting the onrreni The primary pres-ure is represented in 



