1. What is a 3-Phase Current Calculator from kW?

Definition: This calculator determines the current (in amps) in a 3-phase electrical system based on power (in kilowatts), voltage, and power factor.

Purpose: It helps electricians, engineers, and technicians properly size electrical components and ensure safe operation of 3-phase equipment.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( I \) — Current (Amperes)
• \( P \) — Power (Kilowatts)
• \( V \) — Voltage (Volts)
• \( PF \) — Power Factor (dimensionless, between 0 and 1)

Explanation: The formula converts kW to watts (×1000), then divides by the product of √3 (1.732), voltage, and power factor to get current.

3. Importance of 3-Phase Current Calculation

Details: Accurate current calculation is critical for selecting proper wire sizes, circuit breakers, and overload protection devices in 3-phase systems.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What is power factor and why does it matter?
A: Power factor represents efficiency of power usage (1 = perfect). Lower PF means more current is needed for same power.

Q2: What voltage should I use for calculations?
A: Use line-to-line voltage (typically 400V, 480V, or 208V for common 3-phase systems).

Q3: How does this differ from single-phase calculation?
A: Single-phase uses \( I = P/V \), without the √3 factor needed for balanced 3-phase systems.

Q4: What if my system is unbalanced?
A: This calculator assumes balanced load. For unbalanced systems, calculate each phase separately.

Q5: Does this account for efficiency?
A: No, this calculates input current. For motor loads, divide by efficiency to get actual current draw.