THE LOCALISATION OF BREAKS AND FAULTS. 



383 



That is, the line currents are proportional to the deflections 

 divided by their respective shunt readings. 

 For example, say we have 



deflection of 200 divisions with shunt at 1,000 

 300 „ „ „ 500 



160 „ „ „ 200 



Then the line currents are in the proportion of 



200 . 300 . 160 

 200 



or as 



1,000 

 1 



500 



3 : 



4. 



Eeferring again to the diagram, Fig. 225, in position 1, with 

 the slider at on the extreme left the galvanometer is com- 



V/////// 



H'l^-H 



Fig. 226. — Showing Damping of Galvanometer by Bridge Arms. 



pletely cut out of circuit. When the arm is near this position 

 and the shunt S is small the galvanometer is in its least sensi- 

 tive condition, and when near the 10,000 end with a large 

 shunt the galvanometer is In its most sensitive condition. 



Considering the galvanometer and universal shunt connected 

 to the bridge, as in Fig. 226, the ratio arms form a compara- 

 tively low shunt on the galvanometer when the latter is in the 

 most sensitive condition, and this puts a considerable extra 



