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3-Phase AC Power Formula:
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Three-phase electric power is a common method of alternating current electric power generation, transmission, and distribution. It is more efficient than single-phase power for delivering large amounts of power to electric motors and other heavy loads.
The calculator uses the 3-phase power formula:
Where:
Explanation: The formula calculates real power in a balanced 3-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 PF of 1 means all power is real power (useful work), while lower PF indicates reactive power (energy stored and returned to the system).
Tips: Enter line-to-line voltage (V), current (A), and power factor (0 to 1). For purely resistive loads, PF=1. For inductive loads (motors, transformers), PF is typically 0.8-0.9.
Q1: What's the difference between line-to-line and line-to-neutral voltage?
A: In 3-phase systems, line-to-line voltage is √3 times the line-to-neutral voltage. The calculator uses line-to-line voltage.
Q2: What is a typical power factor value?
A: For industrial motors, PF is typically 0.8-0.9. Resistive loads (heaters) have PF=1. Capacitive loads can have leading PF (>1).
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 a balanced 3-phase system. For unbalanced systems, calculate each phase separately and sum the results.
Q5: Why is power factor correction important?
A: Low PF causes higher current for the same real power, increasing energy losses and requiring larger equipment. Utilities often charge penalties for low PF.