Capacitance (Farads)
English : C = ( 0.224 K A) / TD
Metric : C = ( 0.0884 K A) / TD

Energy Stored in Capacitor
E = ½ CV²

Linear charge of a capacitor
I = C (dV/dt)

Total Impedance of a Capacitor (Ohms)
Z = v [ RS² + (XC – XL)² ]

Capacitive Reactance (Ohms)
XC = 1/(2pfC)

Phase Angle Ø
Ideal Capacitors: Current leads voltage 90º
Ideal Inductors: Current lags voltage 90º
Ideal Resistors: Current is in phase with voltage

Dissipation Factor (%)
D.F. = tan d (loss angle)
= ESR / XC
= (2pfC)(ESR)

Quality Factor
Q = cotan d = 1/ DF

Equivalent Series Resistance ESR (Ohms)
ESR = (DF) XC = DF/ 2fC

Power Loss
Power Loss = (2fCV²) (DF)

Power Factor
PF = sin d (loss angle) – cos Ø (Phase angle)

Root Mean Square
rms = 0.707 X Vp

KVA (Kilowatts)
KVA = 2pfCV² X 10­³

Temperature Coefficient of Capacitance
T.C. = [ (Ct –C25) / C25 (Tt – 25) ] X 10^6

Capacitance Drift (%)
CD = [ (C1 – C2) / C1 ] X 100

Ceramic Capacitor Reliability
L0 / Lt = (Vt / V0)X (Tt /T0)^Y

Capacitors in Series
Any Number
1/CT = 1/C1 + 1/C2 + …. + 1/Cn
Two Capacitors
CT = C1 C2 / (C1 + C2)

Capacitors in Parallel
CT = C1 + C2 + …. + Cn

Againg Rate
A.R. = % C / decade of time