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Electrical
     Components
     Laws
     Wire Sizes
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Electrical Laws.  
Ohms Law

V = Volts
R = Resistance (ohms, )
I = Current ( Amps)

Formular Example
V = R * I 5 * 2A = 10Vs
I = V / R 10V / 5 = 2A
R = V / I 10V / 2A = 5

Watts

W = Watts
V = Volts
I = Current ( Amps)

Formular Example
W = V * I 10V * 2A = 20W
I = W / V 20W / 10V = 2A
V = W / I 20W / 2A = 10V
   
W = R * I2 5 * 22 = 20W
W = V2 / R 10V2 / 5 = 20W
R = W / I2 20W / 2A2 = 5
R = V2 / W 10V2 / 20W = 5

 




AC Theory

   
RMS 0.707 Peak voltage

Impedance

AC current in a capacitive or inductive component. Impedance is the resistance ( measured in ohms ) of a reactive component ( capacitor, inductor ) at a certain AC frequency.

Capacitor Inductor
Xc = 1 / ( 2 * Pi * f * C ) Xl = 2 * Pi * f * L
where Pi = 3.14 where Pi = 3/14
  f = frequency in Hz   f = frequency in Hz
  C = capacitance in Farads   L = Inductance in Henry
eg A 100uF cap at 50Hz eg A 20mH inductor at 50Hz
  Xc = 1/(2*3.15*50Hx*0.0001F)   Xl=2*3.14*50Hx*0.02
  Xc = 31.8 ohms   Xl = 6.28 ohms

 

 

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