1. What is 3-Phase Power Calculation?

The 3-phase power calculation determines the real power consumed by a 3-phase induction motor or electrical system. It accounts for voltage, current, and power factor to provide accurate power measurement in watts.

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

Where:

• \( P \) — Real power in watts
• \( V \) — Line-to-line voltage in volts
• \( I \) — Current in amps
• \( PF \) — Power factor (0 to 1)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula calculates the actual power being used in the system, accounting for the phase difference between voltage and current in AC systems.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for sizing electrical equipment, determining energy consumption, calculating efficiency, and ensuring proper circuit protection.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amps, and power factor (typically 0.8-0.95 for motors). All values must be positive (voltage > 0, current > 0, 0 < PF ≤ 1).

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing how effectively current is being converted into useful work.

Q2: Why use √3 in the formula?
A: The √3 accounts for the phase difference in 3-phase systems, converting between line-to-line and phase quantities.

Q3: What's typical power factor for motors?
A: Induction motors typically have power factors between 0.8-0.95 when fully loaded, lower when lightly loaded.

Q4: Is this formula for star or delta connection?
A: This formula works for both star and delta connections as long as you use line-to-line voltage and line current.

Q5: How does this differ from single-phase power?
A: Single-phase power is P = V × I × PF (no √3 factor), as there's no phase displacement between voltages.