THE INDUCTION MOTOR. 



Slip and Torque. 90. Lastly, Fig. 27 represents the torque as afunc- 

 tion of the slip. The curves demonstrate that the maximum torque 

 attainable is entirely independent of the armature resistance. The 

 effect of a great armature resistance consists in shifting the same 

 torque from a small slip to a large one. Again, the full line curve 

 gives the torque for the armature with a resistance of 0.016 ohm per 

 phase, while the broken line curve shows the torque for the squirrel 



350 I - 







s: o. 



30 



50 



SLIP 



80 90 1 00* 



FIG. 27. 



cage armature having a resistance equivalent to six times that of the 

 armature with external starting resistance. 



91. Having thus finished the theory and calculation of the polyphase 

 motor, it behooves us to glance back upon the comparatively easy 

 road by which we have reached a complete solution of a problem 

 which, if treated merely by mathematics, appears to be one of the 



