Steps involved while drawing Current Phasors for RLC Parallel Circuit

For I_L = I_C condition

1. Plot the I_R Phasor in a suitable mm graph paper as per scale considered corresponding to the magnitude of I_R Reading. Consider that I_R Phasor as reference and it will be in Phase with Supply Voltage.


2. Plot the I_C Phasor in the same graph paper with the values of I_C Reading as per the previously considered scale, but that I_C will be placed at the tip of I_R phasor leading the I_R Phasor by 900.


3. From Starting Point (i.e. 0,0) of I_R , draw an arc of value corresponding to I_S Reading represented in the same scale.


4. From tip of the I_C Phasor draw an arc of value corresponding to I_L Reading represented in the same scale.


5. Find out the inter- section Point of the two arcs drawn in steps 3 and 4.


6. From tip of I_C join the above mentioned inter-section point. It will indicate I_L Phasor.


7. From Starting Point (i.e. 0,0) join the mentioned inter-section point. It will indicate I_S Phasor.


8. The Angle formed by I_S with respect to V_S(i.e. I_R also) is called Power Factor Angle. The Power Factor can be calculated from the graph by taking ratio of Base/Hypotenuse

• For other 3 conditions i.e.I_minimum , I_L > I_C and I_L < I_C Steps 1 to 7 should be repeated by taking corresponding Ammeter (I_L, I_R, I_C, I_S) readings.