Three-Phase Power Calculator

Calculate real, reactive, and apparent power in a balanced three-phase AC system.

V
A

Real Power

14.13 kW

Apparent Power16.63 kVA
Reactive Power8.76 kVAR
Phase Voltage277.1 V

Real Power vs Line-to-Line Voltage

Three-Phase Power Calculations

Three-phase systems are the standard for industrial and commercial power distribution.

Formulas (Balanced Load)

Apparent Power = sqrt(3) x V_line x I_line

Real Power = Apparent x Power Factor

Reactive Power = sqrt(Apparent^2 - Real^2)

Phase Voltage = Line Voltage / sqrt(3)

The sqrt(3) factor (approximately 1.732) arises from the 120-degree phase separation between the three phases.

Example Calculation

480 V three-phase, 20 A line current, 0.85 power factor.

  1. 01Apparent: sqrt(3) x 480 x 20 = 16,627 VA = 16.63 kVA
  2. 02Real: 16,627 x 0.85 = 14,133 W = 14.13 kW
  3. 03Reactive: sqrt(16627^2 - 14133^2) = 8,744 VAR = 8.74 kVAR
  4. 04Phase voltage: 480 / 1.732 = 277.1 V

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