444 On a New Method of determining Resistances, 



p I T) 



and the value for — ^ — being known, the values of the others 



may be easily obtained from the observed discharges. 



The shunt-powers being obtained, the values for r and r ! may 

 be eliminated from the following formula, in which S = shunt- 

 power or multiplying-powers of shunt, 



then as 



or 



*-*-* 



r = Ax-\-x, 

 r 1 = Ba? + x> 

 r + r 1 = Ax 4- Bx + 2a?, 



= R+ twice the resistance of the fault. 



Deducting the resistance of the fault from r or r', the distance of 

 the fault from either end will be obtained in units of resistance. 



Experiment (see figs. 1 and 2). 



Galvanometer resistance =5480 B.A. units. 



Resistance of coil =49*39 „ 



Discharge from condenser, galvanometer! ~ Q -,. . • 

 i fi , u i //.n Qn\ V =278 divisions, 



shunted with coil (49*39) . . . J 



Discharge from condenser, galvanometer "1 _onq 

 shunted with Ax (B end free) J ~~ " 



Discharge from condenser, galvanometer) _ ^ fi 

 shunted with Bx (A end free) . J ' 



Shunt values: AB=>1120, resist. = 49*39 units. 

 Aa?= 149-0 „ =36-8 

 Ba?=3620 „ =15-2 



Aa? + Ba?=36*8+ 15*2 = 52-0 



52-0 -49-39 = 2-6; ,-. resist, of fault =1*3 unit. 



36*8— 1*3 = 35'5 units = distance of fault from A, 

 15-2-l-3 = 139 „ „ „ B. 



Tamworth House, 

 Mitcham Common. 



