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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. It indicates how effectively electrical power is being used, with a value between 0 and 1.
The calculator uses the power factor formula for three-phase systems:
Where:
Explanation: The formula calculates how much of the apparent power (the product of voltage and current) is actually doing useful work (real power).
Details: A high power factor (close to 1) indicates efficient power usage, while a low power factor means poor utilization of electrical power, which can lead to increased current and energy losses in the system.
Tips: Enter real power in watts, line-to-line voltage in volts, and current in amperes. All values must be positive numbers. The calculator will automatically compute the power factor.
Q1: What is a good power factor value?
A: Ideally, power factor should be as close to 1 as possible. Values above 0.95 are generally considered good, while values below 0.85 may require power factor correction.
Q2: Why is power factor important for generators?
A: Generators must supply both the real power and reactive power. A low power factor means the generator must supply more current for the same real power, reducing its capacity and efficiency.
Q3: How can I improve power factor?
A: Power factor can be improved by adding capacitors (for lagging power factor) or inductors (for leading power factor) to balance the reactive power in the system.
Q4: What causes low power factor?
A: Inductive loads like motors, transformers, and fluorescent lighting typically cause lagging power factor. Leading power factor can be caused by capacitive loads.
Q5: Does power factor affect electricity bills?
A: Many industrial electricity tariffs include power factor penalties or incentives. Utilities may charge more for low power factor because it increases transmission losses.