What is the difference between lagging power factor and leading power factor?

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Power factor is the ratio of watts (true power) to VA (volt-amperes, also called apparent power). Where the load is resistive only, the power factor is one, or unity, because the voltage waveform and the current waveform are in phase. Thus, for resistive loads only, true power and VA are the same. Where the load is reactive, the load stores energy, releasing it during a different part of the cycle. This shifts the current waveform so that it is offset, or out of phase with the voltage waveform. Reactive loads can be inductive (electric motors), capacitive, or non-linear (rectifier power supplies). When the load is inductive, the inductance tends to oppose the flow of current, storing energy then releasing it later in the cycle. The current waveform lags behind the voltage waveform. When the load is capacitive, the opposite occurs, and the current waveform leads the voltage waveform. So, lagging vs. leading is another way of saying the net reactance is either inductive or capacitive. This is slightly simplistic, and what we are talking about above is really DPF, or Displacement Power Factor. Non-linear loads don't really shift the current waveform, they distort it. The current waveform starts to look like a square wave, and square waves contain harmonics. So non-linear loads add harmonic distortion, and this tends to mimic a capacitively reactive load, adding some leading power factor. So when we say power factor, we really must include DPF plus harmonic distortion in total. One memory aid that may help to remember all this is: ELI the ICE man The L in ELI means inductance. The E (voltage) comes first, then the I (current) lags behind. Inductive reactance produces a lagging power factor. The C in ICE means capacitance. The I (current) comes first (leads) then the E (voltage) comes later. Capacitive reactance produces a leading power factor. Remember, it's always the current waveform that is affected by the reactive load, so you have to think about whether the current is leading or lagging. Most reactive loads are inductive, so at most sites the PF is lagging. One cool tidbit is that capacitive reactance cancels out inductive reactance. So if we have a building full of motors, we can add a bunch of capacitors to improve our power factor, meaning we get as close to unity as we can. Thus we have power factor correction capacitors that are made just for this purpose.
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What is the causes of lag power factor?

When there is an inductive element in the circuit, the current lags behind the voltage. an ideal inductor will make the current lag behind the voltage by 90 degrees.. a capac

Leading and lagging power factor?

The terms, 'leading' and 'lagging' refer to what the load current is doing, relative to the supply voltage (Phasedifference) -never the other way around. If the current is le

What does a Lagging power factor mean?

underdamped Answer A lagging power factor describes a situation in which the load current is lagging the supply voltage. This describes an inductive load, such as a motor,

Why power factor lags?

Actually, it can lead or lag. Power factor is said to be leading if the load is capacitive, and lagging if the load is inductive. Since most reactive loads (like motors) are

What is the disadvantage when power factor is lagging?

Any time the power factor is less than 1, whether it is leading or lagging, the efficiency is less than optimal. As power factor declines, more power is required to do the sam

Which power factor is advantage lagging or leading and why?

A lagging power factor is caused by inductive reactance, which is composed of resistance and inductance -- and the resistance component lowers the supply volts. A leading powe

What is difference between 0.8 leading and 0.8 lagging power factors?

Power factor measures the phase difference between voltage and current. If they are in phase the Power Factor is one. If the current and voltage are out of phase the power fac

Why natural trend to lagging power factor?

Power factor is the cosine of an AC circuit's phase angle, where the expression phase angle is the angle by which a load current lags or leads the supply voltage. Lagging ph

What is difference between 08 leading and 08 lagging power factors?

As a power factor value can only vary between 0 and 1, presumably you mean 0.8, rather than '08'? The terms 'leading' and 'lagging' refer to whether the load current is lead

What determines leading or lagging power factor?

A 'leading' power factor is one in which the load current leads the supply voltage, whereas a 'lagging' power factor is one in which the load current lags the supply voltage.

What do you mean lagging power factor?

A lagging power factor means that the current is lagging behind thevoltage. That means that in the AC cycle (50 or 60 Hz) the currentreaches its peak after the voltage. The am

What is the difference between lagging and leading power factor?

With a lagging power factor the phase of the current lags thevoltage, as happens in an inductive load. With a leading powerfactor the current phase leads the voltage, as happe