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Power Calculation Formula:
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The power calculation formula (P = V × I × PF) determines the real power in an AC electrical circuit by accounting for voltage, current, and power factor. This is essential for accurate power measurement and cost estimation.
The calculator uses the power formula:
Where:
Explanation: The formula calculates the actual power consumed, accounting for the phase difference between voltage and current in AC circuits.
Details: Power factor represents the efficiency of power usage. A PF of 1 means all power is effectively used, while lower values indicate reactive power that doesn't perform useful work but still affects system capacity.
Tips: Enter voltage in volts, current in amperes, and power factor (between 0 and 1). For purely resistive loads (like heaters), use PF=1. For motors, typical PF ranges from 0.7 to 0.9.
Q1: Why is power factor important in power calculations?
A: Power factor determines how much of the apparent power (VA) is actually doing useful work (watts). Low PF means inefficient power usage and may incur penalties from utilities.
Q2: What's the difference between real power and apparent power?
A: Real power (watts) does actual work, while apparent power (VA) is the product of voltage and current. The ratio between them is the power factor.
Q3: When should I use this calculation?
A: Use it when estimating power consumption for AC circuits, especially when planning electrical loads or calculating energy costs.
Q4: How can I improve power factor?
A: Power factor correction capacitors can be added to counteract inductive loads (like motors) and bring PF closer to 1.
Q5: Does this apply to DC circuits?
A: For DC circuits, power is simply V × I since there's no phase difference (PF is always 1).