AC Power Calculator

AC Power Formulas:

\[ P = V \times I \times \cos(\phi) \quad \text{(Single Phase)} \] \[ P = \sqrt{3} \times V \times I \times \cos(\phi) \quad \text{(Three Phase)} \]

Phase Type:

Voltage (V):

Current (I):

Power Factor (cos φ):

Real Power (P):

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1. What is AC Power Calculation?

AC power calculation determines the real power consumed in alternating current circuits. It accounts for voltage, current, and the phase relationship between them through the power factor.

2. How Does the Calculator Work?

The calculator uses standard AC power formulas:

\[ P = V \times I \times \cos(\phi) \quad \text{(Single Phase)} \] \[ P = \sqrt{3} \times V \times I \times \cos(\phi) \quad \text{(Three Phase)} \]

Where:

\( P \) — Real power (Watts)
\( V \) — Voltage (Volts)
\( I \) — Current (Amperes)
\( \cos(\phi) \) — Power factor (unitless)
\( \sqrt{3} \) — Three-phase system constant (≈1.732)

Explanation: Single-phase systems are common in residential applications, while three-phase systems are used in industrial and commercial settings for higher power delivery efficiency.

3. Importance of Power Factor

Details: Power factor represents the ratio of real power to apparent power. A low power factor indicates poor electrical efficiency and may result in utility penalties for commercial users.

4. Using the Calculator

Tips: Select phase type, enter voltage in volts, current in amperes, and power factor (0 to 1). Ensure all values are positive and power factor is within valid range.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between real power and apparent power?
A: Real power (Watts) is the actual power consumed, while apparent power (VA) is the product of voltage and current. Power factor = Real Power / Apparent Power.

Q2: Why is three-phase power multiplied by √3?
A: In balanced three-phase systems, the √3 factor accounts for the phase relationships between the three voltage and current waveforms.

Q3: What is a typical power factor value?
A: Ideal power factor is 1.0. Industrial facilities typically aim for 0.95 or higher. Residential power factors are usually 0.85-0.95.

Q4: How can power factor be improved?
A: Power factor correction capacitors, synchronous condensers, or active power factor correction circuits can improve low power factors.

Q5: Does this calculator work for DC circuits?
A: No, this is specifically for AC circuits. For DC circuits, power is simply P = V × I (no power factor).