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The power factor is defined as the cosine of an angle.

(It's the phase angle between voltage and current.)

The magnitude of the cosine is never greater than ' 1 '.

The theory of Unity Gain states that you cannot get more out than you put in.

If the current maximum of a cycle lags (or leads) the voltage maximum by a fraction x of a cycle, then if you think of the situation where the voltage and current are rotating vectors at an angle x degrees apart, then the only useful power is gained by the component of the current which is in phase with the voltage. So, resolve the current vector into two components, one in the direction of the voltage vector, (Icos(x)) and the other component perpendicular the the voltage vector, (Isin(x)). Then the useful power is gotten by multiplying the bits of voltage and current which are in phase: V times I cos(x). So the power obtained is a factor cos(x) down on the value if V and I were in perfect sync. That's why it's called power factor. It is why Power stations don't like inductive or capacitative loads: they have to supply heavy currents that actually deliver no power. Finally, cos(x) never gets above 1.

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Q: Why the power factor is not more than unity?
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What is the effect of power factor greater than unity on energy bill?

Power factor cannot exceed unity!

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.

Power factor is not greater than unity?

Yes. Power factor is never greater than one, nor less than negative one. It is the cosine of the phase angle, and is the ratio of true versus apparent power.A negative power factor can occur in the case of a generator.

Can power factor be more than one?

No. In the simple case of a linear circuit, the power factor is the cosine of an angle, and that can't be more than 1.

Compressibility factor of steam?

For an Ideal gas(steam), the compressibility factor is obviously unity under all conditions whereas for real gas(steam), the compressibility factor may be less or more than unity based on the actual conditions. With best regards, elavazhgan.

What happens to reactive power in a circuit that has both inductance and capacitance?

Inductors are considered to be a load for reactive power, meaning that they will draw reactive power from the system. Capacitors are considered to be sourced of reactive power, they feed reactive power into the system. If you have a circuit that is at unity (balanced with inductors and capacitors) no reactive power will be drawn from the source. You will have unity power factor. If your circuit is more inductive than capacitive it will be drawing reactive power from the source. The opposite is also true for capacitors.

What does achieve by unity mean?

"Achieve by unity" emphasizes the power of collective efforts. Its general gist is that together, people can accomplish more than they would individually.

What is the effect of induction motor on power factor?

An induction motor has a lagging power factor. Motors of more than about 2 HP are designed to have a power factor of 0.85 or higher.

How you improve power factor in synchronous motor?

Power Factor measures the difference in phase between the current and voltage. When they are in phase the Power Factor is defined as 1. When out of phase the value is less than 1. If they are 180 degrees out of phase the Power Factor will be zero.

A load of 9.41 kVA is equal to what in kW?

For a purely resistive load with a unity power factor, 9.41 kVA would equal 9.41 kW. However some equipment such as a motor will have a power factor less than 1. If the power factor is 0.8 then 9.41 kVA would equal 9.41 x 0.8 kW.

How mach load is used 100kva transformer?

i will try my best to answer this quistion, but u must not mind if i make a mistake! >>> the rating of an elctrical machine depend upon the loses in it. if, there are any losses in the machine due to power factor than the machine will b rated in KW and if there is no loss due to power factor than the machine is rated in KVA. so there are no losses in a transformer due to power factor so it is rated in KVA. as the KW= KVA* power factor so, kVA= KW/power factor here, KVA=100 so, KW= 100*power factor u can derive from here that the load on a transformer depends upon the power factor. as the power is always less than unity so the load will be less than 100KW. thankyou!

Transformers are rated in what?

Transformers are rated in KVA. (this is because the transformer is Unity power factor device i.e.. PF = 1)AnswerThe selection of a transformer is determined by the apparent power of the load, expressed in volt amperes(V.A), the load current, and the line voltage of the supply. The transformer must be able to satisfy these requirements.Transformers are not 'unity power factor' devices, which is precisely why their capacity is expressed in volt amperes, rather than in watts.