1. What is 3-Phase Power?

Three-phase power is a common method of alternating current electric power generation, transmission, and distribution. It's more efficient than single-phase power for motors and other heavy loads because the power transfer is constant.

2. How Does the Calculator Work?

The calculator uses the 3-phase power formula:

Where:

• \( P \) — Power in watts
• \( V \) — Line-to-line voltage in volts
• \( I \) — Current in amps
• \( PF \) — Power factor (unitless, between 0 and 1)
• \( \sqrt{3} \) — Constant for 3-phase systems (≈1.732)

Explanation: The formula calculates real power (actual work done) in a balanced three-phase system.

3. Importance of Power Factor

Details: Power factor represents the ratio of real power to apparent power. A higher PF (closer to 1) means more efficient power usage. Motors typically have PF between 0.8-0.95 when fully loaded.

4. Using the Calculator

Tips:

• Measure line-to-line voltage (typically 208V, 230V, 400V, 480V, etc.)
• Use current reading from one phase
• Typical motor power factors range from 0.8-0.95
• All values must be positive numbers

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between real power and apparent power?
A: Real power (watts) does actual work, while apparent power (VA) is the product of voltage and current. The ratio is power factor.

Q2: Why use √3 in the formula?
A: √3 accounts for the phase difference (120°) between the three phases in a balanced system.

Q3: What's a typical power factor for motors?
A: Induction motors typically have PF of 0.85-0.9 at full load, lower at partial loads.

Q4: How does voltage affect motor power?
A: Power is directly proportional to voltage. A 10% voltage drop means ~10% less power.

Q5: Can I use this for single-phase calculations?
A: No, single-phase uses P = V × I × PF (without the √3 factor).