Page 44 - Electrician - TT (Volume 1)
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ELECTRICIAN - CITS





              Fig 14



















           Appliction of ohms law in series circuit (Fig 15)

           Applying ohms’ law to series circuit, the relation between various current could be stated as below
           Ohm’s law state that I=V/R
           In series circuit I=I  =I  =I R3
                           R1
                               R2
           This could be stated as =V/R=V  /R1+V  /R2+V  /R3
                                               R2
                                                      R3
                                       R1
           Supply voltage V=V  +V  +V
                             R1  R2   R3
           IR=R1I  +R2I  +R3I R3
                        R2
                 R1
           Total resistance= R =R1+R2+R
           Application of series circuit
           •  Cells in torch light
           •  Fuse in circuit

           •  Overload coil in motor starters
           •  Multiplier resistance of a voltmeter

                Fig 15










           Parallel combinatiom of resistance (Fig 16)
           Parallel combination of circuit means two or more resistors its starting points are joined in a one point and other
           ends of resistors are joined in another one point.
           Parallel combination circuits are more used in house wiring installation
           Voltages in parallel combination
           Figure shows parallel circuit diagram. We can conclude that the voltage across the parallel circuit is the same as
           the supply voltage
           That is V=V1=V2=V3









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                                    CITS : Power - Electrician & Wireman - Lesson 5 - 12
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