The Capacitor

The CapacitorBASIC CAPACITOR FORMULASI. Capacitance (farads)English: C = .224 K AMetric: C =T D.0884 K AT DII. Energy stored in capacitors (Joules, watt - sec)E = 1 ⁄2 CV 2III. Linear charge of a capacitor (Amperes)I = CdVdtIV. Total Impedance of a capacitor (ohms)Z = R 2 S + (XC - XL ) 2V. Capacitive Reactance (ohms)1x c =2 π fCVI. Inductive Reactance (ohms)x L = 2 π fLVII. Phase Angles:Ideal Capacitors: Current leads voltage 90°Ideal Inductors: Current lags voltage 90°Ideal Resistors: Current in phase with voltageVIII. Dissipation Factor (%)D.F.= tan (loss angle) = E.S.R. = (2 πfC) (E.S.R.)X cIX. Power Factor (%)P.F. = Sine (loss angle) = Cos (phase angle)fP.F. = (when less than 10%) = DFX. Quality Factor (dimensionless)Q = Cotan (loss angle) = 1D.F.XI. Equivalent Series Resistance (ohms)E.S.R. = (D.F.) (Xc) = (D.F.) / (2 π fC)XII. Power Loss (watts)Power Loss = (2 π fCV 2 ) (D.F.)XIII. KVA (Kilowatts)KVA = 2 π fCV 2 x 10 -3XIV. Temperature Characteristic (ppm/°C)T.C. = Ct – C 25x 10 6C 25 (T t – 25)XV. Cap Drift (%)CC.D. =1 – C 2x 100C 1XVI. Reliability of Ceramic CapacitorsL 0 V= t X T t YL t( Vo) ( To)XVII. Capacitors in Series (current the same)Any Number: 1 = 1 + 1 --- 1C T C 1 C 2 C NC 1 C 2Two: C T =C1 + C 2XVIII. Capacitors in Parallel (voltage the same)C T = C 1 + C 2 --- + C NXIX. Aging RateA.R. = % C/decade of timeDXX. Decibelsdb = 20 log V1V 2METRIC PREFIXESSYMBOLSPico X 10 -12 K = Dielectric Constant f = frequency L t = Test lifeTera X 10 +12 R s = Series Resistance L o = Operating lifeNano X 10 -9Micro X 10 -6 A = Area L = Inductance V t = Test voltageMilli X 10 -3Deci X 10 -1 T D = Dielectric thickness = Loss angle V o = Operating voltageDeca X 10 +1Kilo X 10 +3V = Voltagef= Phase angle T t = Test temperatureMega X 10 +6t = time X & Y = exponent effect of voltage and temp. T o = Operating temperatureGiga X 10 +99