Showing posts with label parallel circuit. Show all posts
Showing posts with label parallel circuit. Show all posts

Friday, December 10, 2010

RLC parallel circuit formula and Phasor diagram

RLC in parallel


RCL parallel circuit can be considered as two reactance's XC and XL where the currents are in phase opposition in parallel with the resistor.
 parallel RLC circuit connection
Through the use of  the phasor diagram the effective total resistance can be found  . It can be observed that IR is at the base of the right triangle and IL minus IC minus IL forming the perpendicular.
The amplitude of the resultant current is the hypotenuse.
 parallel RLC phasor diagram

To calculate the resultant we use the Pythagorean theorem . Ic and IL  are 180 degree out of phase  therefore cancel out. The resultant current is the difference between the two.

RLC parallel connection formula current calculation
              








Impedance  phase angle  is calculated from the difference between IL and IC divided by IR

Monday, November 29, 2010

Series and parallel resistance circuit :explanation

The familiarity of the few circuit building blocks is important in  understanding complex circuits. In this post I will explain the most important ideas in  DC circuits.

From my previous posts I discussed about the Ohms law . This is a continuation of the post about  simple direct current circuits. 
   
Resistors in series
   A series circuit is one in which total line current passes through each and every conductor in the circuit. two or more electric component are considered to be in series in the same current flows through all these component
resistors in series diagram










laws of Series circuit
1. current in all parts of the series circuit is the same
It=I1+I2+I3+In
2. voltage across a group of conductor connected in series is equal to the sum of the individual voltage across individual resistors
Et=E1+E2+E3+En
3. total resistance of a group of conductors connected in series is equal to the sum of the individual resistances
Rt=R1=R2+R3+Rn

Resistors in parallel
  A parallel circuit is one in which current may flow through two or more independent branches.Two or more components are considered in parallel if the same voltage appears across all these components

resistors in parallel diagram











laws of parallel circuits
1. total voltage of a parallel circuit is the same as across each branch of circuit
Et= E1=E2=E3=En
2.Total current is equal to the sum of individual branch currents
It=I1+I2+I3+In
3.The reciprocal of the total resistance of a number of resistors connected in parallel is equal to the sum of the reciprocals of the separate resistances.Total resistance is always less or approximately equal to the values of the smallest resistive branch
1/Rt=1/R1+1/R2+1/R3+1/Rn
 Rt=1/(1/R1+1/R2+1/R3+1/Rn)

Note that : it is important to know that connecting additional resistors in series increases resistance, while connecting additional resistance in parallel decreases the total resistance.