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POWER AND POWER-FACTOR. 



EXPERIMENT XI. DETERMINATION OF RELATION 

 P.KTNVBEN CURRENTS IN BRANCH AND MAIN CIRCUITS. 



DIAGRAM OF CONNECTIONS. 



M i M 2 Source of alternating current. 



R Non-inductive resistance. 



r Inductive resistance. 



R l Variable resistance 



Ai Ammeter reading current in r. 



A-2 Ammeter reading current in R. 



As Ammeter reading total current. 



V Voltmeter reading voltage of branch 

 circuits. 



S Switch for breaking circuit. 



Instructions. Connect in parallel to one terminal of the 

 source of supply of alternating current an inductive and a 

 non-inductive resistance with an ammeter in series with 

 each. 



Join them both to the other terminal of the supply in 

 series with a variable resistance, ammeter, and switch. 



Connect a voltmeter to the points of junction of the 

 two branch circuits. 



Take simultaneous readings on the three ammeters 

 and the voltmeter for several values of the current, which 

 may be varied either by alteration of the voltage of the 

 alternator supplying the circuit, or by varying the non- 

 inductive resistance in the common branch of the circuit. 



For each set of readings construct a triangle to 

 represent the magnitude and phase relations of the 



