Three-Phase Power Calculator

Convert line voltage and current into kW, kVA, kvar and estimated useful output.

Real electrical input
28.6 kW
Apparent power 33.255 kVA
Reactive power 16.97 kvar
Estimated useful output 26.312 kW
Inputs
V
RMS voltage between phases.
A
RMS current in each line conductor.
0–1
Real power divided by apparent power.
%
Optional useful output divided by electrical real input.
Results & Graph
Real electrical input
28.6 kW
Apparent power
33.255 kVA
Reactive power
16.97 kvar
Estimated useful output
26.312 kW

Three-phase apparent, real, and reactive power

Graph 1 • Entered design case Domain-specific illustration generated from the active calculator inputs.
P 28.6 kWQ 16.97 kvarS 33.26 kVAPOWER TRIANGLEPF 0.86
Graph 2 • Engineering outputs Balanced three-phase apparent, real and reactive power.
Real power 28.6 kVA Reactive power 16.97 kVA Apparent power 33.255 kVA
Graph 3 • Calculated response For fixed voltage/current, kW varies with power factor.
0kW 18.0kW 35.9kW 0.5: 16.628 kW 16.6 0.5 0.6: 19.953 kW 20.0 0.6 0.7: 23.279 kW 23.3 0.7 0.8: 26.604 kW 26.6 0.8 0.9: 29.93 kW 29.9 0.9 1.0: 33.255 kW 33.3 1.0
Summary: Real input is 28.6 kW, with 33.255 kVA apparent load.
Summary: For a balanced three-phase load, √3 × line voltage × line current gives 33.255 kVA; at 86% power factor, real input is 28.6 kW.
⚠️ Assumes a balanced sinusoidal three-phase system and line-to-line voltage. Harmonics, unbalance, and waveform distortion are excluded.

Formula & Mathematical Methodology: Three-Phase Power Calculator

S=√3 VLL IL
P=S×PF
Q=S×1−PF²
Useful Output=P×Efficiency
S=√3 VLL IL; P=S×PF; Q=S×√(1−PF²); Useful Output=P×Efficiency
  • : Line-to-line RMS voltage
  • : Line current
  • : Displacement power factor
  • : Apparent, real, and reactive power

Rounding: Displayed values are rounded for readability; calculations retain full floating-point precision.

Worked Example: 480 V, 40 A, 0.86 power factor

Estimate power for a balanced three-phase load with 92% efficiency.

  1. Calculate apparent power using √3 × line voltage × current.
  2. Apply power factor for real kW.
  3. Resolve reactive power and estimated useful output.
Result: The calculator separates kVA, kW, kvar and load output.

Frequently Asked Questions

What is the difference between kW and kVA?

kW is real power; kVA is apparent power. Their ratio is the power factor for the assumed sinusoidal load.

Science & Engineering • Electrical Engineering Guide

How to Use the Three-Phase Power Calculator: Practical Guide & Visual Analysis

Use line-to-line voltage, line current, power factor, and efficiency for a balanced three-phase screening calculation. Whether you are researching three phase power calculator, 3 phase kW calculator, three phase kVA calculator, line voltage current power factor, this interactive tool helps you calculate real, apparent and reactive power for a balanced three-phase load.

Interpreting the 3 Custom Visual Graphs & Key Outputs

As you adjust Line-to-Line Voltage, Line Current, Power Factor, Load Efficiency, the calculator immediately computes Primary result, Supporting calculation metrics, Three calculator-specific visualizations and updates all three domain-specific SVG charts in real time. Instead of relying on a single static figure, you can inspect the primary domain diagram, component breakdown, and multi-point trajectory curve to see how changing your inputs shifts the final result. Use the Compare (up to 3 scenarios) button to evaluate side-by-side variations before making a decision.

Real-World Benchmark & Planning Tips (Global; user-entered values, assumptions and currency)

In our benchmark scenario (480 V, 40 A, 0.86 power factor), The calculator separates kVA, kW, kvar and load output. Keep in mind that balanced sinusoidal three-phase load using line-to-line RMS voltage. For related calculations in Science & Engineering, explore Amps, Watts, Volts, kVA & kWh Power Converter, NEC Wire Ampacity & LED Calculator, Transformer Capacity Sizing Estimator, Pump Power and Operating Cost Calculator.