THE LOCALISATION OF BREAKS AND FAULTS. 



459 



■say ten minutes, during which time testing is carried on 

 without speaking. 



Preliminary balances are taken from each end showing 

 which requires the higher added resistance. Resistances are 

 then added to both ends of the line, so that the balances are 

 made up to the amount agreed upon, which should be about 5 per 

 •ceat. greater than the higher of the two first readings. During 



E, 



Fault. 



Station A. 



L-:r 



Fault 



Station B on same Cable. 



L||l|l|l|lH 

 Fig. 256. — Jordan and Schonau's Earth Overlap (to False Zero). 



the test the added resistances are treated as part of the cable — • 

 that is, when one station earths for the other to test he earths 

 the end of his added resistance as in Fig. 256. 



At each test the added resistance is re-adjusted until the 

 balance agreed upon is obtained, and when both ends get 

 steady readings of the required amount the added resistances 



