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3-Phase kWh Formula:
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The 3-phase kilowatt-hour (kWh) calculation determines the energy consumption in a three-phase electrical system. It accounts for the three alternating currents that are offset in time, providing more power with less conductor material compared to single-phase systems.
The calculator uses the 3-phase power formula:
Where:
Explanation: The formula calculates real power consumption by accounting for the phase relationship in 3-phase systems and the power factor which represents the ratio of real power to apparent power.
Details: Accurate 3-phase kWh calculation is essential for energy monitoring, billing, system design, and efficiency analysis in industrial and commercial electrical systems.
Tips: Enter line-to-line voltage in volts, current in amperes, power factor (typically 0.8-0.95 for motors), and time in hours. All values must be positive, with power factor between 0 and 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 √3 times the line-to-neutral voltage. This calculator uses line-to-line voltage.
Q2: Why is power factor important?
A: Power factor accounts for the phase difference between voltage and current. Lower power factors mean more current is needed for the same real power, increasing losses.
Q3: When is this calculation most accurate?
A: When voltage, current and power factor are stable during the measurement period. For varying loads, integrate over shorter time periods.
Q4: How does this differ from single-phase calculation?
A: Single-phase uses V×I×PF×h/1000. Three-phase adds the √3 factor to account for the three phases.
Q5: What are typical power factors for different loads?
A: Resistive loads: ~1.0, Induction motors: 0.8-0.9 at full load, Fluorescent lights: 0.5-0.9 depending on ballast type.