352 Mr. T. H. Blakesley's Further 



._, , m, m-,m 2 , m 1 m 2 ni 3 s 



.'. E = nci+ — r 2 c 2 + — ^— 2 r d c 3 + " r^ + &c. 



n->n 



]"2 



The series has ^ + 1 terms when there are q transformers 

 The square of this expression will have every term quadratic 

 in current, and be thus amenable to dynamometer treatment. 



The value for one transformer has already been given 

 by me. 



If we multiply through by c h we have the total power CjE 

 given in suitable terms. 



For one transformer, 



or power 



-in 2 ■ m 



771 



*iiDi+-r 2 iD 2 , 



the first term heating the primary; r 2 2 D 2 is the power heating 

 the secondary. 



Therefore the power involved in warming the core by the 

 magnetic changes is 



~ r 2 



jD*,— ?' 22 D 2 =r 2 J. ^iD 2 — 2 D 2 J' 



The Case of Transformers with Primaries in Series. 

 E R 







,^^^ r r/v sgg s^ os* s ^\ m 



E is the E.M.F. of the generator ; 



N the number of magnetic lines in the core ; 



m the number of turns in the primary of a transformer; 



n the number of turns in the secondary of a transformer ; 



C the current in the primary ; 



R its resistance ; 



c the current in the secondary ; 



r its resistance. 



Numerical subscripts being added where required. 



