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AC Power Formula:
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AC power calculation involves determining the real power consumption in an alternating current circuit. Unlike DC circuits, AC power calculations must account for the power factor, which represents the phase difference between voltage and current waveforms.
The calculator uses the AC power formula:
Where:
Explanation: The formula calculates real power by multiplying voltage, current, and power factor. Apparent power (VA) is calculated as V × I without power factor.
Details: Power factor indicates how effectively electrical power is being used. A power factor of 1 means all power is real power, while lower values indicate reactive power that doesn't perform useful work but still requires infrastructure capacity.
Tips: Enter voltage in volts, current in amps, and power factor as a decimal between 0 and 1. All values must be positive, with power factor typically between 0.7 and 1.0 for most AC systems.
Q1: What is the difference between real power and apparent power?
A: Real power (Watts) is the actual power consumed and converted to work, while apparent power (VA) is the product of voltage and current without considering power factor.
Q2: What is a typical power factor value?
A: Residential power factors are typically 0.95-1.0, while industrial loads with motors may have 0.7-0.9. Perfectly resistive loads have PF=1.
Q3: Why is low power factor problematic?
A: Low power factor requires higher current for the same real power, leading to increased energy losses, larger conductors, and potential utility penalties.
Q4: How can power factor be improved?
A: Power factor correction capacitors can be added to counteract inductive loads, bringing the power factor closer to 1.
Q5: Does this calculator work for three-phase systems?
A: This calculator is for single-phase AC systems. Three-phase calculations require additional factors and different formulas.