APPENDIX B. 



377 



magnetizing action of the " load current" in each "rod" of the 

 stator winding is balanced by the magnetizing action of the cur- 

 rent in the rotor rod which is immediately beneath it. This con- 

 dition is approximately realized on account of the low magnetic 

 reluctance of the local magnetic circuit which surrounds a stator 

 slot and a rotor slot as shown in Fig. 247. Figure 9 represents 



band of band of 



stator conductors stator conductors 



phase A phaseB 



Fig. 9. 



a surface view of the rotor rods and end-rings of a two-phase 

 induction-motor rotor, and it shows the positions of two adjacent 

 bands of stator conductors of phase A and phase B, respectively. 

 The arrows in Fig. 9 represent arbitrarily chosen positive direc- 

 tions. All of the rotor rods which lie under a stator band of 

 phase A carry equal currents which are in phase with each other, 

 namely, the currents which are represented by the vectors I, 2, 

 3, 4, 5 and 6 in Fig. 10 ; all of the rotor rods which lie under a 

 stator band of phase B carry equal currents which are in phase 

 with each other, namely, the currents which are represented by 

 the vectors 7, 8, 9, 10, n and 12 of Fig. 10. It is evident that 

 these two sets of currents must be in quadrature with each other 

 because they balance the magnetizing actions of " load currents " 

 in phase A and phase B y respectively. - The currents which 

 flow through the sections a, b, c, etc., of the end-rings cannot 

 be completely determined from the vector diagram of currents * 



* The determination of currents in a network of conductors depends upon the ap- 

 plication of two principles, namely, Kirchhoff's first law together with the condition 

 of minimum dissipation of power as RI* loss in the network. 



