APPENDIX I. 



The following presentation by Mr. Gisbert Kapp of the elementary 

 phenomena in the induction motor is reprinted from his book, "Elec- 

 tric Transmission of Energy," because, in the author's opinion, it is 

 the clearest and most concise logical evolution of the principles un- 

 derlying the theory set forth in the preceding pages. It will repay 

 the student to go over Mr. Kapp's presentation of the subject, and 

 he will understand the vector diagram much more clearly after hav- 

 ing become thoroughly familiar with this extract from the work of 

 a master of the art of exposition. 



Extract from Gisbert Kapp's Electric Transmission 

 of Power On the Induction Motor. 



THE armature conductors may be connected so as to form single 

 loops, each passing across a diameter, or they may all be con- 

 nected in parallel at each end face by means of circular conduc- 

 tors, somewhat in the fashion of a squirrel cage. Either system of 

 winding does equally well, but as the latter is mechanically more sim- 

 ple, we will assume it to be adopted in Fig. 49. The circular end con- 

 nections are supposed to be of very large area as compared witli the 

 bars, so that their resistance may be neglected. The potential of either 

 connecting ring will then remain permanently at zero, and the current 

 passing through each bar from end to end will be that due to the 

 e. m. f. acting in the bar divided by its resistance. It is important 

 to note that the e. m. f. here meant is not only that due to the bar 

 cutting through the lines of the revolving field, but that which re- 

 sults when armature reaction and self-induction are duly taken into 

 account. 



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