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3-Phase Power Formula:
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Three-phase power is a common method of alternating-current electric power generation, transmission, and distribution. It is more efficient than single-phase power for large industrial motors and other heavy loads.
The calculator uses the 3-phase power formula:
Where:
Explanation: The formula calculates the real power in a balanced three-phase system, accounting for the phase difference between voltage and current through the power factor.
Details: Power factor represents the ratio of real power flowing to the load to the apparent power. A higher power factor (closer to 1) indicates more efficient power usage, while a lower power factor means more current is required to deliver the same amount of real power.
Tips: Enter line-to-line voltage in volts, current in amperes, and power factor (between 0 and 1). All values must be valid (voltage > 0, current > 0, 0 ≤ PF ≤ 1).
Q1: What's the difference between line-to-line and line-to-neutral voltage?
A: In 3-phase systems, line-to-line voltage is between any two phases, while line-to-neutral is between a phase and neutral. Line-to-line is √3 times line-to-neutral.
Q2: What is a typical power factor value?
A: For resistive loads it's 1.0, for inductive motors typically 0.8-0.9. Poor power factor (below 0.8) may require correction.
Q3: Can this formula be used for unbalanced loads?
A: No, this formula assumes a balanced 3-phase system. Unbalanced systems require more complex calculations.
Q4: 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 for the same current.
Q5: What are common 3-phase voltage levels?
A: Common voltages include 208V, 240V, 480V (North America) and 380V, 400V, 415V (Europe/Asia).