1. What is 3-Phase Current Calculation?

The 3-phase current calculation determines the current flowing in each phase of a three-phase electrical system. It's essential for designing and analyzing balanced three-phase circuits commonly used in industrial and commercial power systems.

2. How Does the Calculator Work?

The calculator uses the 3-phase current formula:

Where:

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

Explanation: The formula accounts for the balanced three-phase power distribution and the phase relationship between voltage and current.

3. Importance of 3-Phase Current Calculation

Details: Accurate current calculation is crucial for proper sizing of circuit breakers, wires, transformers, and other electrical components in three-phase systems.

4. Using the Calculator

Tips: Enter power in watts, line-to-line voltage in volts, and power factor (typically between 0.8-1.0). All values must be positive (power > 0, voltage > 0, 0 < PF ≤ 1).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line and phase current?
A: In a balanced wye (Y) system, line current equals phase current. In a delta (Δ) system, line current is √3 times phase current.

Q2: What if my system is single-phase?
A: For single-phase systems, use I = P/(V×PF) without the √3 factor.

Q3: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing how effectively current is being converted to useful work.

Q4: What voltage should I use?
A: Use the line-to-line (phase-to-phase) voltage, not the line-to-neutral voltage.

Q5: Is this for balanced systems only?
A: Yes, this calculator assumes a perfectly balanced three-phase system. Unbalanced systems require more complex calculations.