1. What is Power Factor in AC Circuits?

Power Factor (PF) is the ratio of real power (measured in watts) to apparent power (measured in volt-amperes) in an AC electrical system. It represents the efficiency of power usage and indicates how effectively electrical power is being converted into useful work output.

2. How Does the Calculator Work?

The calculator uses the power factor formula:

Where:

• \( PF \) — Power Factor (dimensionless)
• \( \cos \phi \) — Cosine of phase angle between voltage and current
• \( \text{Real Power} \) — Actual power consumed (Watts)
• \( \text{Apparent Power} \) — Product of RMS voltage and current (Volt-Amperes)

Explanation: The power factor ranges from 0 to 1, where 1 indicates perfect efficiency (all power is real power) and 0 indicates poor efficiency (all power is reactive).

3. Importance of Power Factor Calculation

Details: Power factor calculation is crucial for optimizing electrical system efficiency, reducing energy costs, preventing equipment overload, and complying with utility power factor requirements. Low power factor can result in higher electricity bills and reduced system capacity.

4. Using the Calculator

Tips: Enter real power in watts and apparent power in volt-amperes. Both values must be positive numbers greater than zero. The calculator will compute both power factor and the corresponding phase angle.

5. Frequently Asked Questions (FAQ)

Q1: What is considered a good power factor?
A: Generally, a power factor of 0.95 or higher is considered good. Utilities often charge penalties for power factors below 0.85-0.90.

Q2: What causes low power factor?
A: Low power factor is typically caused by inductive loads like motors, transformers, and fluorescent lighting that create phase displacement between voltage and current.

Q3: How can power factor be improved?
A: Power factor can be improved by adding power factor correction capacitors, using synchronous motors, or implementing active power factor correction circuits.

Q4: What's the difference between real, apparent, and reactive power?
A: Real power does useful work, apparent power is the vector sum of real and reactive power, and reactive power supports magnetic fields in inductive equipment.

Q5: Does power factor affect residential electricity bills?
A: Most residential customers are not charged for power factor, but commercial and industrial customers often face power factor penalties in their electricity bills.