kW to Amps Calculator 3 Phase Converter

3-Phase Power Formula:

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

Current (I):

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1. What is the 3-Phase Power Formula?

The 3-phase power formula calculates current (amperes) from power (kilowatts), voltage, and power factor. It's essential for sizing electrical equipment, circuit breakers, and conductors in three-phase systems.

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 3-phase power distribution (√3), and considers the power factor which represents the phase difference between voltage and current.

3. Importance of Current Calculation

Details: Accurate current calculation is crucial for proper electrical system design, preventing overloads, selecting appropriate wire sizes, and ensuring equipment operates within specifications.

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 (power factor between 0 and 1).

5. Frequently Asked Questions (FAQ)

Q1: What is line-to-line voltage?
A: It's the voltage measured between any two phase conductors in a 3-phase system, typically 208V, 380V, 400V, 415V, or 480V in industrial applications.

Q2: Why is power factor important?
A: Power factor represents efficiency of power usage. Lower PF means more current is required for the same real power, increasing losses in the system.

Q3: What's a typical power factor value?
A: For motors under load, PF is typically 0.8-0.9. Resistive loads have PF=1. The calculator defaults to 0.8 if not specified.

Q4: Can this be used for single-phase systems?
A: No, single-phase uses a different formula (I = kW × 1000 / V / PF). This calculator is specifically for balanced 3-phase systems.

Q5: How does this relate to circuit breaker sizing?
A: The calculated current helps determine the appropriate circuit breaker size, which should be 125% of the continuous load current per NEC guidelines.