1. What is a Three Phase kW Calculator?

Definition: This calculator computes the real power in kilowatts (kW) for a three-phase electrical system based on voltage, current, and power factor.

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

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( P_{kW} \) — Real power in kilowatts
• \( V \) — Line-to-line voltage (volts)
• \( I \) — 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 and the phase difference between voltage and current (power factor).

3. Importance of Three Phase Power Calculation

Details: Accurate power calculation ensures proper equipment sizing, energy efficiency, and electrical system safety.

4. Using the Calculator

Tips: Enter the line-to-line voltage in volts, current in amps, and power factor (default 0.8). All values must be > 0, with 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 is √3 used in the formula?
A: The √3 accounts for the phase difference between the three phases in a balanced system.

Q3: What's a typical power factor value?
A: Motors typically have PF of 0.8-0.9, while resistive loads have PF=1. The default 0.8 is common for industrial loads.

Q4: Is this for line-to-line or line-to-neutral voltage?
A: The formula uses line-to-line voltage (the voltage between any two phases).

Q5: How does this differ from single-phase calculation?
A: Single-phase uses P=VI×PF/1000 (without the √3 factor) and uses line-to-neutral voltage.