1. What is 3-Phase Electrical Power?

Definition: This calculator computes the real power in kilowatts (kW) for a balanced three-phase electrical system.

Purpose: It helps electrical engineers, technicians, and electricians determine the actual power consumption in three-phase systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Real power (kilowatts)
• \( V \) — Line-to-line voltage (volts)
• \( I \) — Line current (amps)
• \( PF \) — Power factor (unitless, between 0 and 1)
• \( \sqrt{3} \) — Constant for three-phase systems (≈1.732)

Explanation: The formula accounts for all three phases in the system and converts the result to kilowatts.

3. Importance of 3-Phase Power Calculation

Details: Accurate power calculation is essential for proper equipment sizing, energy efficiency analysis, and electrical system design.

4. Using the Calculator

Tips: Enter the line-to-line voltage in volts, line current in amps, and power factor (default 0.8). All values must be > 0 and PF ≤ 1.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line and phase voltage?
A: In 3-phase systems, line voltage is between two lines, while phase voltage is between a line and neutral (line voltage = √3 × phase voltage).

Q2: What is power factor?
A: Power factor (PF) is the ratio of real power to apparent power, representing how effectively current is converted to useful work (typically 0.8-0.95).

Q3: Why use √3 in the formula?
A: The √3 factor accounts for the 120° phase difference between the three phases in a balanced system.

Q4: Can I use this for single-phase systems?
A: No, for single-phase use \( P_{kW} = (V \times I \times PF)/1000 \) (without the √3 factor).

Q5: How do I measure line current?
A: Use a clamp meter on one conductor of the three-phase system while the load is operating.