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Power Formula:
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Power consumption refers to the amount of electrical energy used by a device or system over time. It's typically measured in watts (W) or kilowatts (kW) and is calculated using voltage, current, and power factor for AC circuits.
The calculator uses the power formula:
Where:
Explanation: This formula calculates the real power consumption 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, energy efficiency assessment, circuit protection sizing, and estimating electricity costs.
Tips: Enter voltage in volts, current in amperes, and power factor (a value between 0 and 1). All values must be positive numbers.
Q1: What is power factor and why is it important?
A: Power factor represents the efficiency of power usage in AC circuits. A lower power factor indicates more reactive power and less efficient energy transfer.
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) is the product of voltage and current, measured in volt-amperes (VA).
Q3: When is the power factor equal to 1?
A: Power factor equals 1 in purely resistive circuits where voltage and current are in phase. This represents the most efficient power transfer.
Q4: How does power factor affect energy bills?
A: Commercial and industrial users may pay penalties for low power factor, as it requires utilities to supply more current for the same real power.
Q5: Can this formula be used for DC circuits?
A: For DC circuits, the formula simplifies to P = V × I since there's no phase difference and power factor is always 1.