Elihu Thomson
1897 Transactions of the American Institute of Electrical Engineers  
THE PRESIDENT:-We are greatly indebted to Mr. Steinmetz for giving us these very definite and complete figures. The induction motor is a new piece of electric mechanism, and data, particularly such data as this, concerning it, are very valuable. lI-e riot only considers the oidinary type of motor, but also, the effect orn the efficiency, torque, speed, etc., when the various factors stelh as resistanice, impedaniee, etc., are exaggerated. The paper is open for discuission. PROF. ELIHu
more » ... OF. ELIHu THomsoN::r. Steinmetz hlas giveni a vast amiiounit of study to the problem of induction motors. I can say that he has done a good thing in giving the results of the work to the world, so tOat it may serve as a guide to others workiin on this general sub lject. The paper is full of material whielh requires a good deal of time and study to discuss, and I look forwNard to the time when in these other promised papers we shall see the rest of the matter presented. The subject is likely to be an exhaustless oie, as the numnber of changes wllich can be ruiog upon this type of apparatus and simnilar types is almnost endless. I simply call attention to what seems to me quite an interesting mLlatter, wlichl would be of course naturally expected, that is comparing Fig. 3 witlh Fig. 9 , one machine run as a motor simply, and the other as an induction generator; we see the speed curves are almost the exact counterpart reflected upward, while the other curves are very much the same, and the breakdown line is marked in very much the same way, by a re-curving backward at a certain elevation above, and below in the other instance. No dloubt furtlher inspectioni of these ver-y initerestig ciurves would discover othier atnalogies between the work of the different motors anid under the different conditions. THE PRESIDENT :-The use of an induction motor as a genieiator is a ver-y initeresting subject, about whiclh there is not vrery muel information now available. Mfr. Steinmetz simply coInsiders it inicidentally in order to complete the scope of his investigations. The stability of their action is very peculiar, anid lie does niot specify the exact conditions, but indicates them. I Iope that poinit will be more fully covered in future papers. PROF. W. E. GOLDSBOROUGH :-It seems to me that one of the mnost interesting points which the paper brings out is tlhe great exactness with whichl a piece of apparatuis can be designed. The curves which are shown in this paper, especially those of Figs. 1 and 2 are particularly valuable to us, in view of the fact that they indicate that a piece of electrical apparatus can be designed with as great, if not greater, accuracy than can any other kind of maclliniery. The points fall upon the curves with great exactness, and if I understand AMr. Steinmetz arighlt, the curves were figured ouit before the machine was operated. I do not know of any other case where the accuracy of the calculations made pre-viouIs to the test of the maclhine lhas been anything like as marked 218 [Julv 26,
doi:10.1109/t-aiee.1897.5570187 fatcat:tf5bopsofbfn5brnaop7vzlryu