30 



ELECTRICAL MACHINERY 



always even, as they go by pairs; for every north pole 

 on a" machine there must be a south pole. In large, low 



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e General View of an a-c Machine, Showing Revolving Field 

 and Stationary Armature. Westinghouse Elec. and Mfg. Co. 



FIG. 7. Turbo-driven Alternator, Showing Turbine and Generator 

 on Same Bed Plate. General Electric Company. 



speed machines the number of poles may be as high as 

 72 or more. With the introduction of the high speed 

 turbine in place of the low speed reciprocating engine, 



