1. What is a 3-Phase kW to Amps Calculator?

Definition: This calculator converts electrical power in kilowatts (kW) to current in amperes (A) for three-phase AC systems.

Purpose: It helps electricians, engineers, and technicians determine the current draw of three-phase equipment based on its power rating.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The formula accounts for the three-phase power relationship and converts kW to watts (×1000).

3. Importance of 3-Phase Current Calculation

Details: Accurate current calculation is essential for proper wire sizing, circuit breaker selection, and electrical system design to prevent overheating and ensure safety.

4. Using the Calculator

Tips: Enter the power in kW, system voltage (default 400V), and power factor (default 0.8). All values must be > 0, with PF between 0.01 and 1.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line and phase voltage?
A: Line voltage is between any two phases, while phase voltage is between a phase and neutral. For delta systems they're equal; for wye, line voltage is √3 × phase voltage.

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

Q3: What's a typical power factor value?
A: Motors typically have 0.8-0.9 PF, lighting 0.95+, and heavily inductive loads can be 0.5 or lower.

Q4: How does this differ from single-phase calculation?
A: Single-phase uses I = P×1000/(V×PF) without the √3 factor.

Q5: What if I know the current and want to find power?
A: Rearrange the formula: P = I×V×PF×√3/1000.