1. What is Power Factor in 3-Phase Systems?

Power factor (PF) is the ratio of real power (P, in watts) to apparent power (S, in volt-amperes) in an AC electrical system. In 3-phase systems, it measures how effectively electrical power is being converted into useful work output.

2. How Does the Calculator Work?

The calculator uses the 3-phase power factor formula:

Where:

• \( PF \) — Power factor (unitless, range 0 to 1)
• \( P \) — Real power in watts (W)
• \( V \) — Line-to-line voltage in volts (V)
• \( I \) — Current in amperes (A)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula calculates the ratio of actual power being used to the total power being supplied to the system.

3. Importance of Power Factor

Details: Power factor is crucial for:

• Energy efficiency assessment
• Electrical system capacity planning
• Reducing utility penalties for low power factor
• Proper sizing of power factor correction equipment

4. Using the Calculator

Tips:

• Enter real power in watts (active power)
• Voltage should be line-to-line measurement
• Current should be measured in each phase
• All values must be positive numbers

5. Frequently Asked Questions (FAQ)

Q1: What is a good power factor value?
A: Ideally 1.0 (perfect). Industrial systems typically aim for 0.95 or higher. Below 0.85 is generally considered poor.

Q2: What causes low power factor?
A: Mainly inductive loads (motors, transformers) that create reactive power. The more out of phase current and voltage are, the lower the power factor.

Q3: How can power factor be improved?
A: Through power factor correction using capacitors or synchronous condensers that offset inductive reactance.

Q4: Is power factor different for single-phase vs three-phase?
A: The concept is the same, but the calculation differs. Single-phase uses PF = P/(V×I) without the √3 factor.

Q5: Why is √3 used in 3-phase calculations?
A: It accounts for the phase difference (120°) between the three voltage waveforms in a balanced system.