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WikiAnswers does not support pictures, so here are the instructions for drawing the diagram yourself.
Draw a circle, centered at the origin. Think in polar coordinates, where radius is power and angle is the phase angle between voltage and current. The convention is that a purely resistive load, with a power factor of 1, has a vector going straight up the Y axis. (As opposed to normal trigonometry, where 0 theta is along the X axis.)
Now, rethink in rectangular coordinates. The length of the vector to the circumference of the circle, is volt-amps, VA or KVA or MVA as appropriate. The Y coordinate is watts, W or KW or MW as appropriate. You can see that, in the resistive case, where the phase angle is zero, that VA and W are equal. We call that power factor = 1.
Now, lets introduce some reactance. Lets say the system has an inductive load with a phase angle (lagging) of 45 degrees. Redraw the vector upwards with a 45 degree angle. Typically, you go clockwise for a capacitive load and counterclockwise for an inductive load. It does not matter which orientation you use, so long as you are consistent in your meanings.
Notice that the Y coordinate is now 0.707 (square root of 2) and the X coordinate is -0.707. Now, VA is still one, because the length of the vector is still one, but Y is 0.707, so watts is 0.707. We call that a power factor of 0.707, because power factor is true versus apparent, i.e. Y/R. If you look at X, you see that it is -0.707. We call X volt-amps-reactive or VAR or KVAR or MVAR as appropriate. Don't worry about the sign; VAR is 0.707, and the negative sign means that it is inductive, as opposed to capacitive.
In the theoretical case of an ideal inductor or capacitor, with zero impedance for the conductors and the source voltage, the vector would be aligned with the X axis, pointing left for inductive and right for capacitive. This means the power factor is zero. Note that VA is still 1. That means that energy is being transferred, with a cost, but the electric meter is standing still because it reads watts, not volt-amps, nor volt-amps-reactive.
You may wonder about the case where the vector points down. That is simply the case of a generator, instead of a load.
What else can I help you with?
What does PF means in single line diagram of a power system?
In a single line diagram of a power system, "PF" typically stands for Power Factor. It is a measure of how efficiently electrical power is being converted into useful work output and is defined as the ratio of real power (measured in watts) to apparent power (measured in volt-amperes). A power factor of 1 indicates that all the power is being effectively utilized, while lower values indicate inefficient use of power, often due to reactive power in the system.
Block diagram of a nuclear power station?
The heart of a nuclear power plant is the nuclear reactor.
Why generators are rated at 0.8 lagging power factor?
Rated power factor
What is low power factor watt meter?
A wattmeter reads the true power of a load, regardless of its power factor.
Is it possible to transmit power with leading power factor?
The power factor depends on the properties of the load, and if any power factor correction is done it has to happen at the load, so that the current in the transmission lines is reduced. Correcting the power factor at the sending end fails to address the problem.
Can I see a Power steering diagram for a 2005 Kia Sedona?
There is a diagram under the related links.
Why should the power factor of a power system be high?
See Related Links
What does PF means in single line diagram of a power system?
In a single line diagram of a power system, "PF" typically stands for Power Factor. It is a measure of how efficiently electrical power is being converted into useful work output and is defined as the ratio of real power (measured in watts) to apparent power (measured in volt-amperes). A power factor of 1 indicates that all the power is being effectively utilized, while lower values indicate inefficient use of power, often due to reactive power in the system.
Wiring diagram for the power seat on a 95 S-10 blazer?
A power see wiring diagram, for your 1995 Chevrolet Blazer, can be obtained from most Chevrolet dealerships. The wiring diagram can also be found at most auto-parts stores.
How do you check to see if a relay is good on a 1989 camaro?
power it up (diagram on back usually) and see if it opens & closes
Why is the power factor at no load less than full load?
That's not possible. The power factor is related to the phase difference between voltage and current on the line. "No load" means 'no current', so power factor is meaningless with no load. If you see a power factor, there must be a load, even if it's some device that you're not aware of.
A pencil has a diameter 7 mm a scale diagram of the pencil has dimeter 3.5 determine the scale factor of the diagram?
scale factor=7/3.5=2
How can you use your completed diagram to find the greatest factor that 20and27 have in common?
According to the diagram, the only and therefore the largest common factor of 20 and 27 is 1.
What is a schematic diagram?
an electronic schematic diagram is a visual presentation that describes the connection between power and device. For better understand see http://www.circuitstune.com/2012/06/what-is-schematic-diagram.html
What is the effect of poor power factor?
See discussion page before answering then delete this line.
What is a diagram showing the prime factorization of a number?
A factor free is a diagram showing the prime factorization of a number.
Why is power factor is cos of angle between voltage and current?
Power factor is the ratio of true power to apparent power -if you refer to the so-called 'power triangle', these correspond to the adjacent and hypotenuse of a right-angled triangle. The cosine of the angle between them is the ratio of hypotenuse (apparent power) to adjacent (true power). As the power triangle is derived from the voltage/current phasor diagram, this is exactly the same angle as that between load current and supply voltage.
