80 ELECTRICAL ENGINEERING 



E g is the generator voltage, 



E is the receiver voltage = 220 volts, 



/ is the load current, 



r is the resistance of each conductor. 



No.l B.& S. 



I r 



FIG. 63. Distributing circuit. 



The power delivered is 



El = 20,000 watts; 

 the current is therefore 



/ = ' = 90.9 amperes; 



the resistance of each conductor at 25 C. is 



r = 0.126 ohms; 

 the voltage drop in each conductor is 



6l = Ir = 90.9 X 0.126 = 11.48 volts; 

 the generator voltage is therefore 



E g = E + 2 Ir = 220 + 22.96 = 242.96 volts; 

 the drop of voltage in the circuit is 



2 l = 2 Ir = 22.96 volts 



= 24296 X 100 per cent = 9.45 per cent. 



The loss of power in the circuit is 



2 7V = 2 X 90.9 2 X 0.1261 = 2090 watts; 

 the power delivered by the generator is 



E g l = 242.96 X 90.9 = 22,100 watts; 

 therefore the power loss is 



2090 

 A O 1AA X 100 per cent = 9.45 per cent; 



Z.,1UU 



and the efficiency of the transmission is 90.55 per cent. 



