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Motor EfficiencyPower Factor BasicsPower Factor and Motor EfficiencyMotor System Power Factor Improvement ProjectSystem Improvement MeasuresThe ResultsConsiderationscrusher ing efficiency. power factor and efficiency of large crusher motors. Power factor is a form of electrical efficiency due to voltage and current waveforms being out of Induction motors have a lagging power factor below unity For a large motor the magnetizing current can be as low as 20% of the rated full load For example rolling mills crushers have varying and fluctuating loads

Induction motors are only one of the kinds of electrical equipment that tend to reduce a plant's power factor. And it's the overall plant system's power factor that counts. There are ways of correcting a low system power factor, so maximum motor power factor isn't vital. System power factor correction is often the better way.

Electric power consumption is rated power divided by motor efficiency. Rated power depends on class of motor (which considers intended duty). Industrial grade motors usually are rated for continuous duty. Motor efficiency requirements are set by 1992 Energy Policy Act (EPACT), primarily for larger motors as used in industry and HVAC.

Motor Efficiency Depends Upon Power Factor 5 A very large opportunity for system-level energy savi ngs comes from using variable speed motor drives. A well-designed pump or fan motor running at half the speed consumes only one-eighth the energy compared to running at full speed. Many older pump and fan installations used fixed-speed motors

· But usually power factor is defined as the motor input power divided by the RMS V*A measurement. A typical example from a textbook. A 1/4 HP capacitor run motor has the following values: Load Effic PF.00 0.0 0.46.25 0.4 0.65.50 0.6 0.75.75 0.7 0.83 1.0 0.75 0.85 1.1 0.77 0.86 1.5 0.70 0.90 Efficiency and Power Factor are not the same..

Power Factor verses Efficiency | Mike Holt's Forum

Electric power consumption is rated power divided by motor efficiency. Rated power depends on class of motor (which considers intended duty). Industrial grade motors usually are rated for continuous duty. Motor efficiency requirements are set by 1992 Energy Policy Act (EPACT), primarily for larger motors as used in industry and HVAC.

Induction motors are only one of the kinds of electrical equipment that tend to reduce a plant's power factor. And it's the overall plant system's power factor that counts. There are ways of correcting a low system power factor, so maximum motor power factor isn't vital. System power factor correction is often the better way.

crusher ing efficiency. power factor and efficiency of large crusher motors. Power factor is a form of electrical efficiency due to voltage and current waveforms being out of Induction motors have a lagging power factor below unity For a large motor the magnetizing current can be as low as 20% of the rated full load For example rolling mills crushers have varying and fluctuating loads

Motor Efficiency Depends Upon Power Factor 5 A very large opportunity for system-level energy savi ngs comes from using variable speed motor drives. A well-designed pump or fan motor running at half the speed consumes only one-eighth the energy compared to running at full speed. Many older pump and fan installations used fixed-speed motors

Electric motor power efficiency has taken center stage. Individuals, corporations, and governments are increasingly interested in saving power, and we now have the technology that can make it possible. Advances in motor control algorithms and cost-effective electronic components for implementing motor drives are creating a revolution in virtually every electric motor market and this article .

· But usually power factor is defined as the motor input power divided by the RMS V*A measurement. A typical example from a textbook. A 1/4 HP capacitor run motor has the following values: Load Effic PF.00 0.0 0.46.25 0.4 0.65.50 0.6 0.75.75 0.7 0.83 1.0 0.75 0.85 1.1 0.77 0.86 1.5 0.70 0.90 Efficiency and Power Factor are not the same..

and 93.7-89.6 for 200, 100, and 50 hp motors, respectively. The power factor (PF) of a motor at a constant rpm will also change as the load changes. Power factors listed in the Depart ment of Energy's MotorMaster+ software (DOE 2005) vary widely among manufacturers, as did the efficiencies determined by Wallace et al. (2002).

Correction of power factor with capacitors. Description: Power factor is the relationship (phase) of current and voltage in AC electrical distribution systems. Under ideal conditions current and voltage are “in phase” and the power factor is “100%.” If inductive loads (motors) are present, power factor less than 100% (typically 80 to 90 .

· But another metric is needed for overall system efficiency — true power factor. Power factor PF is the ratio of real power to apparent power, and is given by the Fig. 2. The relationship of real power, reactive power, and power factor are presented in this power triangle. 2 2 5.

Given that one of the main purposes of energy efficiency is to save money, power factor correction is typically carried out along with energy efficiency retrofits. There are slight energy savings through the reduction of line currents, but the effect tends to be negligible compared with eliminating the power factor fee from the electric bill.

Because the power factor and efficiency of a motor vary with the load of the motor, the equations above must be calculated with the power factor and efficiency ratings at the given load factor. Motor power factors begin to erode as motor operation drops below 75% of rated load and decline sharply below 50% of rated load [3].

Some machines have gone to linear motors to improve responsiveness but they, too, sacrifice efficiency, as linear motors can be much less efficient than rotary motors with gearing. (See “Gearing up for efficiency,” July/August 2009, Energy Efficiency & Technology.) Clamping is another area where hydraulics holds the advantage.

The power factor of an AC electric power system is defined as the ratio active (true or real) power to apparent power, where. Active (Real or True) Power is measured in watts (W) and is the power drawn by the electrical resistance of a system doing useful work; Apparent Power is measured in volt-amperes (VA) and is the voltage on an AC system multiplied by all the current that flows in it.

Causes of Low power factor. The usual reason for the low power factor is because of the inductive load. The current in the inductive load lag behind the voltage. The power factor is therefore lagging. The important inductive loads responsible for the low power factor are the three-phase induction motors (which operate at a 0.8 lagging power .

Motor EfficiencyPower Factor BasicsPower Factor and Motor EfficiencyMotor System Power Factor Improvement ProjectSystem Improvement MeasuresThe ResultsConsiderationscrusher ing efficiency. power factor and efficiency of large crusher motors. Power factor is a form of electrical efficiency due to voltage and current waveforms being out of Induction motors have a lagging power factor below unity For a large motor the magnetizing current can be as low as 20% of the rated full load For example rolling mills crushers have varying and fluctuating loads