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3-Phase Power Factor Formula:
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Power Factor (PF) is the ratio of real power (measured in watts) to apparent power (measured in volt-amperes) in an AC electrical system. For 3-phase systems, it's calculated using the real power, line voltage, and line current.
The calculator uses the 3-phase power factor formula:
Where:
Explanation: The formula calculates how effectively electrical power is being converted into useful work output in a 3-phase system.
Details: Power factor indicates the efficiency of power usage. A low power factor (typically <0.85) means poor utilization of electrical power, which can lead to higher electricity costs and require larger equipment.
Tips: Enter the motor's real power in watts, line voltage in volts, and line current in amps. All values must be positive numbers. The calculator will compute the power factor (a value between 0 and 1).
Q1: What is a good power factor for motors?
A: Most 3-phase motors have a power factor between 0.85 and 0.95 at full load. Values below 0.85 may indicate inefficiency.
Q2: How can I improve power factor?
A: Power factor correction capacitors can be installed to improve power factor by offsetting the inductive reactance of motors.
Q3: Why is power factor important for utilities?
A: Utilities often charge penalties for low power factor because it requires them to provide more current for the same real power.
Q4: Does power factor vary with load?
A: Yes, power factor is typically lowest at no load and improves as the motor approaches full load.
Q5: What's the difference between leading and lagging power factor?
A: Lagging power factor (common with motors) means current lags voltage. Leading power factor (with capacitors) means current leads voltage.