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3-Phase Power Formula:
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The 3-phase power calculation is used to determine the real power (in watts) in a balanced three-phase electrical system. It's essential for sizing motors, transformers, and other electrical equipment.
The calculator uses the 3-phase power formula:
Where:
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.
Details: Accurate power calculation is crucial for proper equipment sizing, energy efficiency analysis, and electrical system design. It helps prevent overloading and ensures safe operation.
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 (voltage > 0, current > 0, 0 < PF ≤ 1).
Q1: What's the difference between line and phase voltage?
A: In 3-phase systems, line voltage is between two lines, while phase voltage is between a line and neutral. For wye connections, line voltage = √3 × phase voltage.
Q2: What is a typical power factor for motors?
A: Induction motors typically have power factors between 0.8-0.9 at full load, dropping at lighter loads. Synchronous motors can achieve unity (1.0) or leading power factors.
Q3: How does this differ from single-phase power calculation?
A: Single-phase power is P = V × I × PF (no √3 factor). Three-phase delivers more power with less conductor material.
Q4: What if my system is unbalanced?
A: This calculator assumes balanced loads. For unbalanced systems, calculate each phase separately and sum the results.
Q5: Can I calculate apparent power (kVA) with this?
A: Apparent power would omit the PF term: S = √3 × V × I. Real power (kW) is what actually does work.