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3-Phase Power Formula:
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The 3-phase power calculation determines the real power (in watts) delivered by a three-phase electrical system. This is essential for sizing generators, transformers, and other electrical equipment in industrial and commercial applications.
The calculator uses the 3-phase power formula:
Where:
Explanation: The formula accounts for the phase relationship in three-phase systems and the power factor which represents the ratio of real power to apparent power.
Details: Power factor (PF) is crucial in AC circuits as it indicates how effectively electrical power is being converted into useful work. A lower PF means more current is required to deliver the same amount of real power, leading to increased losses in the system.
Tips: Enter line-to-line voltage in volts, current in amperes, and power factor (typically between 0.8 and 1 for most industrial loads). All values must be valid (voltage > 0, current > 0, PF between 0-1).
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 one phase and neutral. The calculator uses line-to-line voltage.
Q2: What is a typical power factor value?
A: For generators, typical PF values range from 0.8 (inductive loads) to 1 (resistive loads). Many industrial loads have PF between 0.85-0.95.
Q3: Why is √3 used in the formula?
A: The √3 factor accounts for the 120° phase difference between the three phases in a balanced system.
Q4: Can I use this for single-phase calculations?
A: No, for single-phase systems use P = V × I × PF without the √3 factor.
Q5: How does this relate to generator sizing?
A: This calculates real power output. Generator capacity is typically rated in kVA (apparent power), which equals √3 × V × I without the PF factor.