Basic Electrical Installation Work

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c. It can also expressed as: X V I C C C Definition Capacitive reactance (XC) the oppo- sition a. Example Calculate the reactance 150μF capacitor and 0. current capacitive circuit.142 50Hz 0.Baisc Electrical Installation Work 196 Capacitive reactance (XC) the opposition a. given the formula: X fC C ) 1 2π Ω where and are defined before and the capacitance the circuit. ∴ Ω XL 3.7 Impedance The total opposition current flow a.c. circuit called impedance and given the symbol Thus impedance the combined opposition to current flow the resistance, inductive reactance and capacitive reactance of the circuit and can calculated from the formula: Z ) Ω or Z V I T T Definition The total opposition current flow in an a. causes the current the cir- cuit lead ahead the voltage.2 Ω For inductive reactance: X fL L 2π where 50Hz and 0.05H.c.2. ∴ 6 1 2 3.142 50Hz 150 F 21. causes the current the circuit lead ahead the voltage, as shown Fig. 10.c. For capacitive reactance: 2 C X fC 1 π where 50Hz and 150μF 150 106 F. current capaci- tive circuit. circuit called impedance and given the symbol Z.05H inductor they were separately connected the 50Hz mains supply. .05H 15