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3 phase power calculator: kW to amps per phase at 400 V

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11 kW at 400 V three phase, power factor 1 works out at 15.88 A per phase: 11 kW × 1,000 ÷ (√3 × 400 V × 1) = 15.88 A per phase.

What to convert

Between 0.01 and 1,000,000

Supply

Leave empty for the standard. WA is 240 V single phase and 415 V three phase.

Between 100 and 480. For 12, 24 or 48 V, use the battery tools

12, 24 or 48 V? Use the battery runtime calculator

Power factor

Leave empty for 1 (heaters, kettles) or 0.8 for kVA (generators).

Power factor is at most 1 (and at least 0.1)

See result ↓

Your result

Result

15.88 A per phase

11 kW × 1,000 ÷ (√3 × 400 V × 1) = 15.88 A per phase

You typed
11 kW at 400 V three phase, power factor 1
Apparent power (kVA)
11
Power factor used
1

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How we calculated this

  • Multiply the volts by the power factor. Amps are the watts divided by that.
  • On three phase, the volts are also multiplied by the square root of three before dividing.
  • kW is kVA times power factor. An empty voltage means the standard at the meter.

Full method, tables and sources: Watts to amps calculator

  1. Check the inputs

    11 kW at 400 V three phase, power factor 1

  2. Use the formula

    11 kW × 1,000 ÷ (√3 × 400 V × 1) = 15.88 A per phase

This version starts with 11 kW on three phase, like a three-phase EV charger. Type your kW, or switch to amps to kW.

3 phase power: what to know

Official source

  • Three phase is 400 V at the meter in the eastern states (ESC Distribution Code) and 415 V (±6%) in WA (Western Power).
  • A standard WA three-phase connection is 32 A per phase: about 22.17 kW at 400 V, or 23 kW at 415 V.
  • 400 V is line to line. Each phase to neutral is 230.94 V (400 ÷ √3), and the amps are per phase.
Three phase kW to amps per phase at 400 V and 415 V
kW400 V415 V (WA)400 V, power factor 0.85
57.22 A per phase6.96 A per phase8.49 A per phase
1115.88 A per phase15.30 A per phase18.68 A per phase
1521.65 A per phase20.87 A per phase25.47 A per phase
2231.75 A per phase30.61 A per phase37.36 A per phase
2434.64 A per phase33.39 A per phase40.75 A per phase
2536.08 A per phase34.78 A per phase42.45 A per phase
3043.30 A per phase41.74 A per phase50.94 A per phase
5072.17 A per phase69.56 A per phase84.90 A per phase
  • A standard WA three-phase connection is 32 A per phase, and that is for everything on it, not for one load. At 415 V, 22 kW draws 30.61 A per phase and 24 kW draws 33.39 A per phase. Ask a licensed electrician.
  • The last column is the same kW at power factor 0.85, an induction motor at full load: 11 kW draws 18.68 A per phase, not 15.88 A per phase.

Every cell is the calculator on this page, run for that row. The power factor 0.85 column is one of Schneider Electric's practical values (Official source). The other columns are at power factor 1, the figure for a heater or kettle (Estimate). 400 V is the standard at the meter in the eastern states and 415 V is the standard in WA (Official source). A standard WA three-phase connection is 32 A per phase (Official source). Source: Western Australian Service and Installation Requirements (April 2023), p.41: 32 amps per phase, three-phase (415 volts). An estimate, not electrical advice. Ask a licensed electrician.

Three phase loads: EV chargers and motors

Three-phase EV chargers

An 11 kW three-phase charger runs 16 A on each phase (11.04 kW) and a 22 kW three-phase charger 32 A (22.08 kW).

Source: Worked out as 3 phases × 230 V × 16 A; Worked out as 3 phases × 230 V × 32 A (Estimate). Checked 30 September 2026.

From 400 V line to line the calculator gives 15.93 A per phase for 11.04 kW and 31.87 A per phase for 22.08 kW, just under those 16 A and 32 A: 400 V between phases is 230.94 V on each phase, not 230 V. A car that charges on one phase takes one of the three, 3.68 kW from an 11 kW three-phase charger. How long that takes for each car: the EV charging time calculator.

A motor draws more as it starts

An induction motor started direct on line draws about 7.5 times its rated current.

Source: Schneider Electric Electrical Installation Guide, induction motors: starting current about 7.5 × rated current direct on line (read via the Wayback Machine) (Official source). Checked 30 September 2026.

For the 11 kW row at power factor 0.85 that is about 140 A per phase for a moment, against 18.68 A per phase once it runs. The calculator and the table show the running current only.

For power points, power factor and 230 or 240 V, see the main watts to amps calculator.