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Calculate Power in AC Circuit

AC Power Formula:

\[ P = V_{rms} \times I_{rms} \times PF \]

volts
amps

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1. What is AC Power Calculation?

Definition: This calculator computes the real power in an AC circuit based on RMS voltage, RMS current, and power factor.

Purpose: It helps electrical engineers and technicians determine the actual power consumption in AC systems.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ P = V_{rms} \times I_{rms} \times PF \]

Where:

Explanation: The product of voltage and current gives apparent power, which is then scaled by the power factor to get real power.

3. Importance of AC Power Calculation

Details: Accurate power calculation ensures proper circuit design, energy efficiency, and correct sizing of electrical components.

4. Using the Calculator

Tips: Enter the RMS voltage in volts, RMS current in amps, and power factor (default 1.0 for purely resistive loads). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing the phase difference between voltage and current.

Q2: What's a typical power factor value?
A: 1.0 for resistive loads, 0.8-0.95 for motors, and lower for highly inductive loads.

Q3: Why use RMS values?
A: RMS (root mean square) values represent the equivalent DC values that would produce the same power.

Q4: Does this work for three-phase systems?
A: No, this is for single-phase. Three-phase requires multiplying by √3 (1.732).

Q5: What's the difference between real and apparent power?
A: Real power (watts) does actual work, while apparent power (VA) is the product of V and I without power factor.

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