kW to Amp 3 Phase Calculator

3-Phase Power Formula:

\[ I = \frac{kW \times 1000}{\sqrt{3} \times V \times PF} \]

Current (Amperes):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the 3-Phase Power Formula?

The 3-phase power formula calculates current (amperes) from power (kilowatts) in a balanced three-phase electrical system. It accounts for the phase relationship in three-phase power and the power factor of the load.

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

\[ I = \frac{kW \times 1000}{\sqrt{3} \times V \times PF} \]

Where:

\( I \) — Current in amperes (A)
\( kW \) — Power in kilowatts (kW)
\( V \) — Line-to-line voltage (V)
\( PF \) — Power factor (unitless, 0 to 1)
\( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula converts kW to watts (×1000), accounts for the 3-phase relationship (√3), and adjusts for the power factor which represents the phase difference between voltage and current.

3. Importance of Current Calculation

Details: Accurate current calculation is essential for sizing circuit breakers, wiring, transformers, and other electrical components to ensure safe and efficient operation of electrical systems.

4. Using the Calculator

Tips: Enter power in kW, line-to-line voltage in volts, and power factor (typically 0.8-0.95 for motors). All values must be positive numbers (power factor between 0.01 and 1).

5. Frequently Asked Questions (FAQ)

Q1: What is power factor and why is it important?
A: Power factor represents the ratio of real power to apparent power. It's crucial because it affects the actual current drawn by a load.

Q2: What's the difference between line-to-line and line-to-neutral voltage?
A: In 3-phase systems, line-to-line voltage is between any two phases, while line-to-neutral is between a phase and neutral. This calculator uses line-to-line voltage.

Q3: What are typical voltage values for 3-phase systems?
A: Common voltages include 208V, 240V, 380V, 400V, 415V, 480V, and 600V, depending on region and application.

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

Q5: What if my power factor is unknown?
A: For resistive loads (heaters, incandescent lights), use 1.0. For motors, 0.8 is a common estimate if exact value is unknown.