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Power Formula:
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The power formula P = V × I × PF calculates electrical power in AC circuits, where P is power in watts, V is voltage in volts, I is current in amperes, and PF is the power factor (unitless).
The calculator uses the power formula:
Where:
Explanation: This formula calculates the real power in an AC electrical circuit, accounting for the phase difference between voltage and current through the power factor.
Details: Accurate power calculation is essential for electrical system design, generator sizing, energy consumption analysis, and ensuring proper equipment operation and safety.
Tips: Enter voltage in volts, current in amperes, and power factor (between 0 and 1). All values must be valid positive numbers with power factor between 0-1.
Q1: What is power factor and why is it important?
A: Power factor represents the ratio of real power to apparent power. It's important because it affects the efficiency of power delivery and the sizing of electrical equipment.
Q2: What's the difference between real power and apparent power?
A: Real power (P) is the actual power consumed, measured in watts. Apparent power (S = V × I) is the product of voltage and current, measured in volt-amperes.
Q3: When is power factor equal to 1?
A: Power factor equals 1 in purely resistive circuits where voltage and current are in phase, meaning all power is real power with no reactive component.
Q4: What are typical power factor values?
A: Typical values range from 0.7 to 0.95. Industrial facilities often have power factors around 0.8-0.9, while residential areas typically have 0.95-0.98.
Q5: How does power factor affect generator sizing?
A: Lower power factors require larger generators to deliver the same real power because the generator must supply both real and reactive power components.