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**Zephon** · August 6th, 2006

Heh. It's been a really long time, huh, Shiori? Anyway, I too haven't posted in a while.

Anyway, about the power consumption question. What Phoenix said is pretty much true, but I would like to add something. He forgot to mention the effects of inductance and capacitance in the power consumption. What Phoenix said about multiplying current and voltage is true for resistive circuits.

In a pure resistive circuit, all the elements have a resistance, and no capacitante/inductance. This way, all the power is dissipated (power given by current * voltage). But when there are inductors or capacitors, these components drain current too, but they don't really dissipate the energy (there is always a small resistance in the component that does this, but let's not get too deep), they accumulate the energy in electrostatic/electromagnetic energy form.

The REAL power consumed by your machine is due to the resistive part of the circuits only. When you directly multiply the line's voltage * current, you have what is called APPARENT power (given in volt-amperes VA, not watts W), which is usually a little bit higher than the real power.

In most residences in 110V areas, there is also a 220V plug. This is because there are 3 lines that come to your house. One is the ground (reference), taht is always 0V. The other is 110V alternate current (comparing to the reference), and the other is also 110V alternate current when compared to the reference. But both 110V lines have a 180° phase between each other (they are sinusoidal waves), and that makes the difference between them 220V. So the question about having 110V and 220V in the same house is answered by: yes, you can have both, you just need to choose the correct lines to use in your plug.

Ok, it was a little bit too technical. Maybe people who study (or are willing to study) electrical engineering will like it.

__________________
But there is someone who remembers you
Someone waiting for a sign that leads the way to you
There is someone who will die for you
Keep that in mind when the hope fails

August 6th, 2006	#6 (permalink)
Zephon Key To The Universe Join Date: Jul 2001 Location: Stratosphere Posts: 2,707	Heh. It's been a really long time, huh, Shiori? Anyway, I too haven't posted in a while. Anyway, about the power consumption question. What Phoenix said is pretty much true, but I would like to add something. He forgot to mention the effects of inductance and capacitance in the power consumption. What Phoenix said about multiplying current and voltage is true for resistive circuits. In a pure resistive circuit, all the elements have a resistance, and no capacitante/inductance. This way, all the power is dissipated (power given by current * voltage). But when there are inductors or capacitors, these components drain current too, but they don't really dissipate the energy (there is always a small resistance in the component that does this, but let's not get too deep), they accumulate the energy in electrostatic/electromagnetic energy form. The REAL power consumed by your machine is due to the resistive part of the circuits only. When you directly multiply the line's voltage * current, you have what is called APPARENT power (given in volt-amperes VA, not watts W), which is usually a little bit higher than the real power. In most residences in 110V areas, there is also a 220V plug. This is because there are 3 lines that come to your house. One is the ground (reference), taht is always 0V. The other is 110V alternate current (comparing to the reference), and the other is also 110V alternate current when compared to the reference. But both 110V lines have a 180° phase between each other (they are sinusoidal waves), and that makes the difference between them 220V. So the question about having 110V and 220V in the same house is answered by: yes, you can have both, you just need to choose the correct lines to use in your plug. Ok, it was a little bit too technical. Maybe people who study (or are willing to study) electrical engineering will like it. __________________ But there is someone who remembers you Someone waiting for a sign that leads the way to you There is someone who will die for you Keep that in mind when the hope fails