1. What is 3-Phase Motor Power?

The 3-phase power formula calculates the real power in a three-phase electrical system. It's essential for sizing motors, determining electrical loads, and ensuring proper circuit protection.

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)

Explanation: The √3 factor accounts for the phase difference in three-phase systems. The power factor represents the ratio of real power to apparent power.

3. Importance of Power Calculation

Details: Accurate power calculation is crucial for proper motor selection, circuit breaker sizing, energy efficiency analysis, and electrical system design.

4. Using the Calculator

Tips: Enter line-to-line voltage in volts, current in amps, and power factor (typically 0.8-0.95 for motors). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between line and phase voltage?
A: In 3-phase systems, line voltage is between any two lines, while phase voltage is between any line and neutral. For delta connections, they're equal; for wye, line voltage is √3 × phase voltage.

Q2: What is a typical power factor for motors?
A: Induction motors typically have power factors between 0.8-0.95 at full load, lower at partial loads. Always check motor specifications.

Q3: How does this differ from single-phase power calculation?
A: Single-phase uses P = V × I × PF without the √3 factor. Three-phase delivers more power with less conductor material.

Q4: Can I use this for generator output calculation?
A: Yes, the same formula applies for calculating generator output power when you know voltage, current, and power factor.

Q5: What about efficiency?
A: This calculates electrical input power. Mechanical output power would multiply this result by the motor's efficiency (typically 80-95%).