THE POLYPHASE CIRCUIT. 303 



The power given to each branch load circuit is ce watts. 

 Since there are three such branch circuits, the total power 

 transmitted by the line to the branch circuits is See watts. 



ET 



In the star connection c = C and e = hence in 



v 3 

 E 

 this case, total power = 3 c e = 3 C , Q = \/~3~C E. 



\/ o 



C 



In the mesh-connected system c = . -^--and e = E, con- 



\/ o 



C 



sequently power of system = 3 c e = 3 -7=^- E = A/IT C E. 



V 3 



Thus in either case the power is the same and is equal 

 to V3 CE watts. 



The relations just given should be verified by means 

 of the following Experiment : 



EXPERIMENT XLIV. DETERMINATION or THE POWER 

 TRANSMITTED BY A S-PHASE CIRCUIT (LOAD NON-INDUCTIVE). 



DIAGRAMS OF CONNECTIONS. 



MiO MiO- 



MsO ^^ MsO- 



FlG. 151. 



M 1} M 2 , M 3 Terminals supplied with 3-phase alternating 



current. 



R l} R 2 , R 3 Equal non-inductive resistances. * 

 -4 1} A 2 Ammeters. 

 ^1? ^2 Voltmeters. 



Instructions. In order to verify the formulae for both 

 star and mesh connected systems, the connections should 

 be made in turn according to both systems, as indicated 

 in the diagrams shown above. 



* Banks composed of equal number of similar incandescent lamps form a 

 suitable non-inductive load. A still more convenient form of 3-phase resis- 

 tance is a liquid form with three symmetrical blades capable of being dipped 

 into the solution simultaneously to any desired extent. 



