1. What is 3-Phase Current Calculation?

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

Purpose: Essential for electrical engineers, technicians, and electricians to properly size wires, circuit breakers, and other electrical components.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( I \) — Current (amps)
• \( P_{kW} \) — Power (kilowatts)
• \( V \) — Voltage (volts)
• \( PF \) — Power factor (unitless, between 0 and 1)
• \( \sqrt{3} \) — Constant for three-phase systems (≈1.732)

Explanation: The formula converts kW to watts (×1000), then divides by the product of voltage, power factor, and the 3-phase constant.

3. Importance of 3-Phase Current Calculation

Details: Accurate current calculation prevents electrical hazards, ensures proper equipment operation, and helps meet electrical code requirements.

4. Using the Calculator

Tips: Enter the power in kW, system voltage (default 480V), and power factor (default 0.85). Power factor must be between 0.01 and 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 electrical power is being used (typically 0.8-0.95 for industrial equipment).

Q2: Why is √3 used in the formula?
A: The square root of 3 accounts for the phase difference between the three phases in a balanced system.

Q3: What voltage should I use?
A: Common three-phase voltages are 208V, 240V, 480V, or 600V. Use your system's line-to-line voltage.

Q4: Can I use this for single-phase systems?
A: No, use I = P×1000 / (V×PF) for single-phase systems (without the √3 factor).

Q5: How does power factor affect current?
A: Lower power factor means higher current for the same real power, requiring larger conductors and equipment.