RATINGS AND GUARANTEES. 



157 



That is to say, to each conductor in the group g there is a cor- 

 responding symmetrically located conductor in the group h with 

 an oppositely flowing current in it. On the other hand, the 

 magnetizing action of the conductors which lie within the angular 

 distance a from the line AB is unbalanced, and this unbal- 



Fig. 106. 



anced magnetizing action is the demagnetizing action of the arm- 

 ature on the magnetic circuit represented by the dotted line <. 

 The value of this demagnetizing action, expressed in ampere- 

 turns, is found by multiplying the number of conductors * within 

 the space 2a by the current flowing in each. That is : 



* If a wire encircles an iron rod which constitutes a magnetic circuit, then the iron 

 rod encircles the wire. In reckoning an ampere-turn, one must be sure either that the 

 wire encircles the iron rod which constitutes the magnetic circuit, or that the magnetic 

 circuit encircles the wire. 



