How Many Amps Is 428 kW at 400V?

428 kW at 400V draws about 726.78 amps on an AC three-phase circuit at PF 0.85, typical for commercial HVAC, industrial motors, rooftop units, and three-phase panel loads. Actual current varies with equipment power factor and duty cycle.

428 kW at 400V, AC three-phase (PF 0.85)

726.78 Amps

428 kilowatts at 400V on AC three-phase ≈ 726.78 amps

AC Single Phase (PF 0.85)1,258.82 A

DC (ideal baseline)1,070 A

Try: 200kW at 400V 150kW at 400V 125kW at 400V 100kW at 400V

Volts

Amps (AC three-phase, PF 0.85)

726.78

Formulas

DC: kW to Amps

I_(A) = 1000 × P_(kW) ÷ V_(V)

1000 × 428 ÷ 400 = 428,000 ÷ 400 = 1,070 A

AC Single Phase (PF = 0.85)

I_(A) = 1000 × P_(kW) ÷ (PF × V_(V))

428,000 ÷ (0.85 × 400) = 428,000 ÷ 340 = 1,258.82 A

AC Three Phase (PF = 0.85)

I_(A) = 1000 × P_(kW) ÷ (√3 × PF × V_L-L), where V_L-L is the line-to-line voltage

428,000 ÷ (1.732 × 0.85 × 400) = 428,000 ÷ 588.88 = 726.78 A

Equipment & Circuit Sizing

Energy Cost

428 kW costs $72.76/hour at $0.17/kWh (rates last reviewed April 2026). See breakdown.

Power Factor Reference (AC three-phase)

How the line current for 428 kW at 400V changes with load power factor, on the same AC three-phase circuit basis the rest of the page uses. DC has no power factor; PF 1.0 represents resistive AC loads.

Load Type	PF	428 kW at 400V (AC three-phase)
Resistive (heaters, incandescent)	1	617.76 A
Fluorescent lamps	0.95	650.28 A
LED lighting	0.9	686.41 A
Synchronous motors	0.9	686.41 A
Typical mixed loads	0.85	726.78 A
Induction motors (full load)	0.8	772.21 A
Computers (without PFC)	0.65	950.41 A
Induction motors (no load)	0.35	1,765.04 A

AC Conversion Comparison

On DC, 428kW at 400V draws 1,070A. AC single-phase at PF 0.85 pulls 1,258.82A because reactive current is added on top of the real power. Three-phase at the same voltage needs only 726.78A per line since the same 428kW is shared across three conductors instead of one.

Circuit Type	Formula	Result
DC	428,000 ÷ 400	1,070 A
AC Single Phase (PF 0.85)	428,000 ÷ (0.85 × 400)	1,258.82 A
AC Three Phase (PF 0.85)	428,000 ÷ (1.732 × 0.85 × 400)	726.78 A

Other kW Values at 400V

kW	AC 3-Phase per line, PF 0.85	AC 1-Phase PF 0.85
15 kW	25.47 A	44.12 A
18 kW	30.57 A	52.94 A
20 kW	33.96 A	58.82 A
22 kW	37.36 A	64.71 A
25 kW	42.45 A	73.53 A
30 kW	50.94 A	88.24 A
35 kW	59.43 A	102.94 A
40 kW	67.92 A	117.65 A
50 kW	84.9 A	147.06 A
60 kW	101.89 A	176.47 A
75 kW	127.36 A	220.59 A
100 kW	169.81 A	294.12 A
125 kW	212.26 A	367.65 A
150 kW	254.71 A	441.18 A
200 kW	339.62 A	588.24 A

Same kW, Other Voltages

Each destination page leads with the interpretation most common for that voltage, so the amps shown below use the same basis as the page you'd land on: single-phase for residential voltages, three-phase for commercial/industrial panel voltages, DC for low-voltage.

electrical_services 428 kW at 208V = 1,397.66A (3-phase) electrical_services 428 kW at 460V = 631.98A (3-phase) electrical_services 428 kW at 480V = 605.65A (3-phase) electrical_services 428 kW at 575V = 505.59A (3-phase)

Related Calculations

bolt 428,000W to amps at 400V payments 428,000W running cost cable Wire size for 726.78A at 400V (3Φ)

Frequently Asked Questions

How many amps is 428 kW at 400V?expand_more

428 kW at 400V draws about 726.78 amps on an AC three-phase circuit at PF 0.85. Alternate cases at the same voltage: 1,070A on DC, 1,258.82A on AC single-phase.

Why do industrial systems use kW instead of watts?expand_more

Industrial equipment operates at higher power levels. 428 kW is easier to express than 428,000W. The math is identical, just scaled by 1000.

Is 428 kW single-phase or three-phase?expand_more

428 kW is typically three-phase in commercial and industrial settings.

How many amps does a 428 kW EV charger draw at 400V?expand_more

400V is commercial/industrial panel voltage, not a typical AC EVSE feed to a vehicle. On three-phase 400V, 428 kW works out to about 726.78A per line (three-phase at PF 0.85). In practice, 400-480V three-phase is usually the AC input to a DC fast charger (50-350 kW CCS/NACS stations like Tesla Superchargers), which rectifies to DC and delivers that directly to the vehicle, rather than an AC EVSE connector. A 428 kW figure at 400V is most likely the AC feed to a smaller commercial cabinet or the control-side input of a larger DC fast charger, not an at-the-car AC current.

How does three-phase affect the amps for 428 kW?expand_more

Three-phase at 400V draws 726.78A per line versus 1,258.82A single-phase. Less current per conductor means smaller wire and lower I²R losses.

This calculator provides estimates for reference purposes only. Always consult a licensed electrician and verify compliance with the National Electrical Code (NEC) and local electrical codes before performing any electrical work.