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Note that this is an engineering convention, not a concept from pure physics. When you multiply voltage by current, the total "power" in volt*amps can be a combination of two types of "power". 1. active power = V*I*cos(theta) and 2. reactive power = V*I*sin(theta) where (theta) is the phase angle between the voltage and current. A physicist would say that V*I*sin(theta) is NOT power since it is performing zero work.

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How do you find whether it is inductor or capacitor if only power factor is given?

in case of inductor or capacitor power factor is always zero.as power factor is cosine of phase angle between voltage and current. in case of inductor and capacitor phase angle between voltage and current is 90 so it become zero so if given power factor is zero then it can be inductor or capacitor.


What is the power factor of AC generator when the reactive power is equal to zero?

Per factor is 1 when reactive power is zero.


When do you use Power Factor?

You use power factor when the load is not resistive, i.e. when it is reactive, and the phase angle between voltage and current is not zero.


How the capacitor valve calculate for a for a load?

I assume that you are asking how to calculate the 'value' of a capacitor? Well, it depends what it is used for. If, for example, it is used to improve the power factor of a load, then it is first necessary to determine what the load's existing reactive power is; then, you need to know what reactive power is necessary with the power factor at its desired value; finally you need to difference between the actual and the desired values of reactive power -and this will be the necessary value for the capacitor. Power factor correction capacitors are rated in reactive volt amperes, not farads.


How do you calculate capacitor rating for improving power factor?

Power-factor capacitors are rated in reactive volt amperes. To determine the appropriate rating, it is necessary to determine the existing (inductive) reactive power of the load, then determine the amount of (capacitive) reactive power necessary to achieve the desired power factor (it's rarely economical to try and achieve unity power factor), and this will be the necessary reactive power of the capacitor bank.The capacitance of power-factor correction capacitors is not really relevant to the calculation, which is why they are rated in reactive volt amperes, rather than in farads.


Why dc supply is a unity power factor?

Power factor is a measure of the ratio between the "True Power" and the "Apparent Power" of a system. THe variation from unity arises from the effect of certain components (namely capacitors and inductors) on an AC waveform, causing a phase shift between the current and the voltage. As a DC supply does not suffer from these reactive losses there is no reactive power and the current and voltage are always "in phase". With a phase angle of 0 degrees, the power factor is the cosine of the angle... cos 0 = 1 therefore unity power factor!


What does unity power factor UPF mean?

Unity power factor has a value of 1.0. This means the current and voltage waveforms are in phase. This is only possible if the net load is non-reactive (resistive). If the load is either capacitively or inductively reactive, the power factor will be other than unity. If an inductively reactive load such as a motor is offset by a capacitively reactive load such as a PF correction capacitor, it is possible to acheive a net load that has unity power factor. Some loads, such as resistance heaters, are intrinsically non-reactive, and present a unity power factor.


What are the effects of reactive power?

inductance and capictances, lowpower factor


How do you calculate kvar of capacitor bank if you know only the kw?

Your question is rather vague. Are you asking how do you determine the reactive power of a capacitor bank necessary to improve the power factor of a load (in which case, is it a single-phase or a three-phase load), or are you asking how to convert a capacitor bank's capacitance into reactive power?If the former, then you need to know the reactive power of the load before power factor-improvement, and the resulting reactive power after power-factor improvement, and the difference between these two will tell you how much reactive power you need to add in the form of capacitors.


What is the relationship between the firing delay angle and the input power factor?

The firing delay angle is the point in the AC cycle at which a thyristor starts conducting. By adjusting this angle, the power factor of the system can be controlled as it affects the balance between real power and reactive power. A smaller firing delay angle can improve the power factor by reducing the phase difference between voltage and current.


Power factor formula?

Power factor is defined as the ratio of real power over total power. Total power is the vector sum of real and reactive power.


Why reactive power is named as reactive?

Actually reactive power is a power which flows in between load to source which is a reactive action of the power given from source to load.the given power to load will not be utilised fully.some power will be oscillating from load to source.this is called reactive power.