Calculate AC Power Draw

Three-Phase Power Formula:

\[ P = V \times I \times \sqrt{3} \times \cos(\phi) \]

Power Draw (P):

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1. What is Three-Phase Power Calculation?

Three-phase power calculation is used to determine the electrical power consumption in three-phase AC systems. It considers voltage, current, and power factor to provide accurate power measurements for industrial and commercial applications.

2. How Does the Calculator Work?

The calculator uses the three-phase power formula:

\[ P = V \times I \times \sqrt{3} \times \cos(\phi) \]

Where:

\( P \) — Power in watts (W)
\( V \) — Line-to-line voltage in volts (V)
\( I \) — Current in amperes (A)
\( \sqrt{3} \) — Constant for three-phase systems (approximately 1.732)
\( \cos(\phi) \) — Power factor (unitless, range 0-1)

Explanation: This formula calculates the real power in a balanced three-phase system, accounting for the phase relationship between voltage and current.

3. Importance of Power Factor

Details: Power factor represents the efficiency of power usage in AC circuits. A power factor of 1 indicates perfect efficiency, while lower values indicate reactive power consumption that doesn't perform useful work but still requires infrastructure capacity.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amperes, and power factor (between 0 and 1). All values must be positive, with power factor typically ranging from 0.7 to 1.0 for most industrial applications.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between single-phase and three-phase power?
A: Single-phase uses two wires (hot and neutral) while three-phase uses three or four wires, providing more stable power delivery and higher efficiency for large loads.

Q2: Why is √3 used in three-phase calculations?
A: √3 accounts for the 120-degree phase separation between the three phases in a balanced system, converting line-to-line voltage to phase voltage.

Q3: What is a typical power factor value?
A: Industrial motors typically have 0.8-0.9 power factor, while resistive loads have 1.0. Utilities often penalize customers with power factors below 0.9.

Q4: Can this calculator be used for single-phase systems?
A: No, for single-phase systems use P = V × I × cos(φ) without the √3 factor.

Q5: How does power factor affect energy costs?
A: Low power factor increases current requirements, leading to higher energy losses, larger equipment sizing, and potential utility penalties.