
AC Components and Circuits RLC Circuit Analysis
Section 81 Series RLC Circuits Series RLC Circuit When X_{L} is greater than X_{C}, the phase is positive.  When X_{L} is less than X_{C}, the phase is negative  When X_{L} = X_{C} the impedance (Z_{T}) is the same as R, and there is no phase angle.  Procedure Analysis of a series RLC circuit, given the values of V_{T}, X_{L}, X_{C}, and R Step 1: Calculate the total impedance Z_{T} = Ö  R^{2} + (X_{L}  X_{C})^{2}  Step 2 Calculate the total current Step 3 Determine the current for each component I_{R} = I_{L} = I_{C} = I_{T} Step 4 Calculate the voltage for each component  V_{R} = I_{T} x R
 V_{L} = I_{T} x X_{L}
 V_{C} = I_{T} x X_{C}
Step 5 Determine the phase angle for each component and the total phase angle  q_{R} = 0º
 q_{L} = –90º
 q_{C} = 90º
 Examples Endless Examples & Exercises When V_{L} is greater than V_{C}, the phase is positive.  When V_{L} is less than V_{C}, the phase is negative  When V_{L} = V_{C} the voltage across the resistor (V_{R}) is dental to the source voltage V_{T})  Voltage phasors for RLC circuits are identical to those for impedance. The special point where where the reactances are equal (and the reactive voltage is zero
