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Power Formula:
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Power consumption refers to the electrical energy used by a device or system over time. It is calculated using voltage, current, and power factor to determine the actual power being consumed in watts.
The calculator uses the power formula:
Where:
Explanation: This formula calculates the real power consumption by accounting for the phase difference between voltage and current in AC circuits through the power factor.
Details: Accurate power calculation is essential for electrical system design, energy efficiency analysis, circuit protection sizing, and cost estimation for electrical consumption.
Tips: Enter voltage in volts, current in amperes, and power factor (between 0 and 1). For purely resistive loads, power factor is 1. For inductive or capacitive loads, power factor is less than 1.
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 means more apparent power is needed to deliver the same real power, resulting in energy losses.
Q2: What is the difference between real power and apparent power?
A: Real power (P) is the actual power consumed and measured in watts. Apparent power (S) is the product of voltage and current measured in volt-amperes (VA). Real power = Apparent power × Power factor.
Q3: When should I use power factor correction?
A: Power factor correction is recommended when power factor drops below 0.85-0.90, as it reduces energy losses, improves voltage regulation, and may lower electricity costs.
Q4: How does this apply to DC circuits?
A: For DC circuits, power factor is always 1, so the formula simplifies to P = V × I.
Q5: What are typical power factor values?
A: Resistive loads: 1.0, Induction motors: 0.8-0.9, Fluorescent lighting: 0.5-0.9, Computers: 0.6-0.7. Power factor varies with load conditions.