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Power Factor Formula:
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Power Factor is the ratio of real power (P) to apparent power (S) in an AC electrical system. It represents the cosine of the phase angle between voltage and current waveforms, indicating how effectively electrical power is being used.
The calculator uses the power factor formula:
Where:
Explanation: The formula calculates the power factor by dividing the real power (actual work being done) by the product of voltage and current (apparent power).
Details: Power factor is crucial for electrical efficiency. A low power factor indicates poor utilization of electrical power, leading to higher energy costs, increased current flow, and potential equipment damage. Utilities often charge penalties for low power factor.
Tips: Enter real power in watts, voltage in volts, and current in amperes. All values must be positive numbers greater than zero for accurate calculation.
Q1: What is a good power factor value?
A: A power factor of 1.0 (unity) is ideal. Values above 0.95 are considered good, while values below 0.85 may incur utility penalties.
Q2: What causes low power factor?
A: Inductive loads like motors, transformers, and fluorescent lighting create phase displacement between voltage and current, resulting in low power factor.
Q3: How can power factor be improved?
A: Power factor correction capacitors can be installed to counteract inductive reactance and bring the power factor closer to unity.
Q4: What's the difference between leading and lagging power factor?
A: Lagging power factor occurs when current lags voltage (inductive loads), while leading power factor occurs when current leads voltage (capacitive loads).
Q5: Why is power factor important for industrial applications?
A: Industrial facilities with low power factor pay higher electricity bills, require larger conductors and equipment, and experience reduced system capacity.