Basic Electrical Installation Work

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f. If the current lags the voltage shown Fig. Figure 10.f.7, p. is said leading. circuit the power consumed given the product the volt- age and current, because d. is lagging, and the current leads the voltage shown Fig. When con- sidered over one complete cycle, the positive and negative portions are equal, showing that the average power consumed pure inductor capacitor is zero.2 2.05 π Ω ∴ π Ω For (b): Z X Z 2 2 2 ( ) (100 (53.8 shows the voltage and current waveform for pure inductor and pure capacitor.f. also equal to: p. power purely inductive and purely capacitive circuits.5, say that the p. In electric circuit more power taken from the supply than fed back into it, since some power dissipated the resistance the circuit, and therefore: P ) In any d.f.f.03A ∴ Ω Power and power factor Power factor (p.) defined the cosine the phase angle between the current and voltage. The power waveform obtained from the product and every instant the cycle.Alternating current theory and electrical machines 201 For (a): X fC X C C 6 1 2 ( ) 1 2 50Hz F 53.2 Ω ∴ Ω Ω For (c): I V Z I (A) 230 V 113.f. can seen that the power waveform reverses every quarter cycle, indicating that energy alter- nately being fed into and taken out the inductor and capacitor.c. cos R T φ R Z V V The electrical power circuit the product the instantaneous values of the voltage and current.) defined the cosine the phase angle between the current and voltage: p. . 10.6, the p.c.05 113. Inductors store energy magnetic field and capacitors electric field.f. 10.c. Power Power I I V V Pure inductor Pure capacitor FIGURE 10. From the trigonometry the impedance triangle shown in Fig. cos φ Definition Power factor (p. 10.This shows that inductors and capacitors store energy during one part of the voltage cycle and feed back into the supply later the cycle. circuit voltage and current are phase.8 Waveform for the a