1. What is 3-Phase Current?

The 3-phase current is the current flowing in each phase of a three-phase electrical system. It's calculated based on the total power, line voltage, and power factor of the system.

2. How Does the Calculator Work?

The calculator uses the 3-phase current formula:

Where:

• \( I \) — Phase current (Amperes)
• \( P \) — Total power (Watts)
• \( V \) — Line voltage (Volts)
• \( PF \) — Power factor (unitless, 0 to 1)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula accounts for the balanced three-phase system where power is evenly distributed across all three phases.

3. Importance of Phase Current Calculation

Details: Accurate current calculation is crucial for selecting proper wire sizes, circuit breakers, and other electrical components to ensure safe and efficient operation of three-phase equipment.

4. Using the Calculator

Tips: Enter total power in watts, line-to-line voltage in volts, and power factor (typically between 0.8 and 1 for most industrial loads). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is line voltage vs phase voltage?
A: Line voltage is between any two phases, while phase voltage is between a phase and neutral. In a balanced system, line voltage = phase voltage × √3.

Q2: What if power factor is unknown?
A: For resistive loads (heaters, incandescent lights), use 1. For motors, typical values are 0.8-0.95. When in doubt, use 0.85 as a reasonable estimate.

Q3: Does this work for both delta and wye configurations?
A: Yes, as long as you use the correct line voltage value for your system configuration.

Q4: How accurate is this calculation?
A: The calculation is mathematically precise for balanced systems. In real-world applications, actual current may vary due to imbalances or harmonics.

Q5: Can I use this for single-phase calculations?
A: No, this is specifically for three-phase systems. Single-phase current is calculated as I = P / (V × PF).