192 



J HI'; HOY AL SOCIETY OF CANADA 



The relation of the Primary and also of the Secondary Currents 

 to Time is shown in Figui'e (2) for various values of a. From this 

 figure it may be seen that, while the Primary Current is a simple ex- 



lî> 



16 



'<:o 



Fig. 2 



a^ 



îsS 



32. 



iG 



ponential zero at zero time and of a finite value at infinity, the Secon- 

 dary, always of negative sign, is a double exponential zero at zero 

 time and at infinity. Oscillogram No. 57 gives an actual record of 

 a Transient of this nature, the Oscillograph \'ibrators being connected 

 across non-inductive Shunts in the Primary and Secondary of a 10 — 5 

 Ampere Instrument Transformer. 



