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What is the power factor and how is it usually expressed mathematically?
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Is power factor defined as volt amps divided by apparent power?
No. The volt ampere (V.A) is the unit of measurement of apparent power. Power factor is true power (expressed in watts) divided by apparent power (expressed in volt amperes).
What is the difference between unity power factor to 8 power factor?
Power factor does not go above 1. It is the cosine of the phase angle between voltage and current and, as such, can range between +1 and -1, although it should be understood that a negative power factor is mathematically equivalent to a generator - when looking at the load as if it is a motor - or vice versa. Unity power factor is applicable for a resistive load. A typical power factor for a big motor is about 0.92. A theoretical power factor of zero, corresponding to a phase angle of 90 degrees, would mean that the load is purely inductive or capacitive, and that the power supply and conductors are also ideal or theoretical.
What method improve power factor?
The most common method of improving the power factor of a load is to connected a capacitor or capacitor bank, of appropriate reactive power (expressed in reactive volt amperes), in parallel with the load.
When induction motors is used for power factor correction what is called?
I'm not sure I've ever seen an induction motor used to correct power factor; it is usually the induction motors that are causing the poor power factor. "Power factor correction" is usually accomplished by adding capacitors to the system to counteract the inductance of large motors.
How do you calculate actual power factor?
The power factor of a circuit is defined as the cosine of the phase angle -which is the angle by which the supply current lags or leads the supply voltage in AC circuits.Power factor is always expressed as either a 'lagging power factor' or as a 'leading power factor'.The terms 'lagging' or 'leading' describe the relationship of the supply current to the supply voltage. Since current lags voltage in an inductive circuit, 'lagging power factors' describe inductive circuits; since current leads voltage in capacitive circuits, 'leading power factors' describe capacitive circuits. In practice, lagging power factors are more common than leading power factors, because most practical loads are inductive (e.g. motors, etc.).Power factors are normally expressed as a decimal (e.g. '0.8 lagging') although, in the past they were often expressed as a percentage (e.g. '80% lagging'). 'High' power factors tend towards unity, whereas 'low' power factors tend towards zero.In terms of power, the cosine of a circuit's phase angle and, therefore, its power factor is the ratio of that circuit's true power (expressed in watts) and its apparent power (expressed in volt amperes).Power factor has no effect whatsoever upon the energy consumed by a load, but it does effect the amount of current drawn from the supply. 'Low' power factors result in unnecessarily-large load currents for any given load, which mean that the supply utilities need to use larger than necessary conductor sizes (expensive!). For industrial or commercial (but not residential) loads, therefore, it is often desirable to 'improve' the load's power factor towards unity, which acts to reduce the load current. This is most-usually done by installing capacitors close to the load, and is termed 'power-factor correction' or 'power-factor improvement'. Capacitors used in this way are rated in reactive volt amperes, rather than in microfarads.
Efficiency can be express mathematically as?
Efficiency = Output/Input. This is usually expressed as a percentage but may be given in the form of a ratio.Another AnswerEfficiency is output power divided by input power, normally expressed as a percentage.
How is the power factor in a resistive circuit expressed mathematically in terms of the effective and rms powers?
1.plus 2.minus 3.multiplied by 4.divided by
Is power factor defined as volt amps divided by apparent power?
No. The volt ampere (V.A) is the unit of measurement of apparent power. Power factor is true power (expressed in watts) divided by apparent power (expressed in volt amperes).
What is 108 expressed as the producted of power of its prime factor?
22 x 33 = 108
The efficiency of a machine is usually expressed in?
The efficiency of a machine is usually expressed as a percentage. The ideal efficiency of a machine is 100-percent.Another AnswerThere are no units of measurement for efficiency, because you are comparing like with like: output power divided by input power.
How are power factor correction units sized?
Power factor is the cosine of the angle by which the load current lags or leads the supply voltage. It is expressed as a per-unit value: e.g. 0.8; in the past it has been expressed as a percentage value , e.g. 80%.
What is the difference between unity power factor to 8 power factor?
Power factor does not go above 1. It is the cosine of the phase angle between voltage and current and, as such, can range between +1 and -1, although it should be understood that a negative power factor is mathematically equivalent to a generator - when looking at the load as if it is a motor - or vice versa. Unity power factor is applicable for a resistive load. A typical power factor for a big motor is about 0.92. A theoretical power factor of zero, corresponding to a phase angle of 90 degrees, would mean that the load is purely inductive or capacitive, and that the power supply and conductors are also ideal or theoretical.
How calculate power factor on three face generator?
I think you mean 'three phase', not 'three face'!Power factor is a function of the load, notthe generator. The power factor of the load can be determined from its true power (expressed in watts) divided by its apparent power (expressed in volt amperes). For a balanced load, this can be done by manipulating the following equation:True Power = 1.732 VL IL x power factorWhere VL and ILare the line voltage and line current.For an unbalanced load, it is rather more complicated than can be explained in this forum.
When induction motors is used for power factor correction what is called?
I'm not sure I've ever seen an induction motor used to correct power factor; it is usually the induction motors that are causing the poor power factor. "Power factor correction" is usually accomplished by adding capacitors to the system to counteract the inductance of large motors.
Minimum acceptable value of power factor FOR LIGHTING and MOTOR CIRCUITS?
Usually for a power factor lower that 90% a service charge will be added to the monthly electrical bill. On power factor correction calculations try to get the power factor up to 95%.
What method improve power factor?
The most common method of improving the power factor of a load is to connected a capacitor or capacitor bank, of appropriate reactive power (expressed in reactive volt amperes), in parallel with the load.
How do you calculate actual power factor?
The power factor of a circuit is defined as the cosine of the phase angle -which is the angle by which the supply current lags or leads the supply voltage in AC circuits.Power factor is always expressed as either a 'lagging power factor' or as a 'leading power factor'.The terms 'lagging' or 'leading' describe the relationship of the supply current to the supply voltage. Since current lags voltage in an inductive circuit, 'lagging power factors' describe inductive circuits; since current leads voltage in capacitive circuits, 'leading power factors' describe capacitive circuits. In practice, lagging power factors are more common than leading power factors, because most practical loads are inductive (e.g. motors, etc.).Power factors are normally expressed as a decimal (e.g. '0.8 lagging') although, in the past they were often expressed as a percentage (e.g. '80% lagging'). 'High' power factors tend towards unity, whereas 'low' power factors tend towards zero.In terms of power, the cosine of a circuit's phase angle and, therefore, its power factor is the ratio of that circuit's true power (expressed in watts) and its apparent power (expressed in volt amperes).Power factor has no effect whatsoever upon the energy consumed by a load, but it does effect the amount of current drawn from the supply. 'Low' power factors result in unnecessarily-large load currents for any given load, which mean that the supply utilities need to use larger than necessary conductor sizes (expensive!). For industrial or commercial (but not residential) loads, therefore, it is often desirable to 'improve' the load's power factor towards unity, which acts to reduce the load current. This is most-usually done by installing capacitors close to the load, and is termed 'power-factor correction' or 'power-factor improvement'. Capacitors used in this way are rated in reactive volt amperes, rather than in microfarads.
