89 



2,400 volts, 20 poles. Armature-conductor 

 490 by 11.8 mils. Current density 4,000 

 amperes per square inch. Resistance of 

 armature 1.2 ohm. Total number of con- 

 ductors on armature 3,440, divided into 

 two parallels of 1,720 each. Field-coils of 

 320 turns, exciting current 13.5 amperes. 

 Exciting power 17,200 ampere turns. 

 The interpolar space is 0.75 inch, and the 

 area of pole-pieces 14.5 square inches. 

 From these data it is possible to calculate 

 the total flow of the lines. It is in 

 English measure z — . 130, and the elec- 

 tromotive force of an equivalent con- 

 tinuous current machine would be 1,150 

 volts. The ratio between this figure and 

 the electromotive force of the alternator is 

 2.15 which agrees fairly well with the theo- 

 retical value of 2.30 mentioned above. 

 The resistance of the field is 12.8 ohms, 

 and the exciting energy 2,340 watts, or 

 only 2 3 per cent, of the total output. 



The Moedey Altehnator. 



This is also a disk machine ; but with 

 revolving magnets and fixed armature 



