First - a simple question
Right or Wrong? Power = Voltage x Current
That statement is correct for DC systems but there are two major complications for AC systems.
The value of current and voltage keeps changing. Which value do you use ?
The voltage and the current may not be in phase. Multiplying the current and the voltage when they are not in phase requires and adjustment to compensate for the phase. It is this phase shift that forces us to define Real, Apparent and Reactive Power. This phase shift occurs when a power source feeds an inductive or capacitve load". Most loads are either inductive (motors) or resistive (heaters) and therefore the phase shift is typically in one direction.
Right or Wrong? Power = Voltage x Current
That statement is correct for DC systems but there are two major complications for AC systems.
The value of current and voltage keeps changing. Which value do you use ?
The voltage and the current may not be in phase. Multiplying the current and the voltage when they are not in phase requires and adjustment to compensate for the phase. It is this phase shift that forces us to define Real, Apparent and Reactive Power. This phase shift occurs when a power source feeds an inductive or capacitve load". Most loads are either inductive (motors) or resistive (heaters) and therefore the phase shift is typically in one direction.
A motor has a winding. A wound conductor essentially defines an inductor. Thus the winding presents the resistance of the wound wire and the inductance resulting from the winding.
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