How Many Amps Is 387 kW at 400V?

At 400V, 387 kW pulls approximately 657.16 amps on AC three-phase (PF 0.85). This is the case typical for commercial HVAC, industrial motors, rooftop units, and three-phase panel loads. Always verify against the equipment nameplate for actual install sizing.

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

657.16 Amps

387 kilowatts at 400V on AC three-phase ≈ 657.16 amps

AC Single Phase (PF 0.85)1,138.24 A

DC (ideal baseline)967.5 A

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

Volts

Amps (AC three-phase, PF 0.85)

657.16

Formulas

DC: kW to Amps

I_(A) = 1000 × P_(kW) ÷ V_(V)

1000 × 387 ÷ 400 = 387,000 ÷ 400 = 967.5 A

AC Single Phase (PF = 0.85)

I_(A) = 1000 × P_(kW) ÷ (PF × V_(V))

387,000 ÷ (0.85 × 400) = 387,000 ÷ 340 = 1,138.24 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

387,000 ÷ (1.732 × 0.85 × 400) = 387,000 ÷ 588.88 = 657.16 A

Equipment & Circuit Sizing

Energy Cost

387 kW costs $65.79/hour at $0.17/kWh (rates last reviewed April 2026). See breakdown.

Power Factor Reference (AC three-phase)

How the line current for 387 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	387 kW at 400V (AC three-phase)
Resistive (heaters, incandescent)	1	558.59 A
Fluorescent lamps	0.95	587.99 A
LED lighting	0.9	620.65 A
Synchronous motors	0.9	620.65 A
Typical mixed loads	0.85	657.16 A
Induction motors (full load)	0.8	698.23 A
Computers (without PFC)	0.65	859.36 A
Induction motors (no load)	0.35	1,595.96 A

AC Conversion Comparison

On DC, 387kW at 400V draws 967.5A. AC single-phase at PF 0.85 pulls 1,138.24A because reactive current is added on top of the real power. Three-phase at the same voltage needs only 657.16A per line since the same 387kW is shared across three conductors instead of one.

Circuit Type	Formula	Result
DC	387,000 ÷ 400	967.5 A
AC Single Phase (PF 0.85)	387,000 ÷ (0.85 × 400)	1,138.24 A
AC Three Phase (PF 0.85)	387,000 ÷ (1.732 × 0.85 × 400)	657.16 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 387 kW at 208V = 1,263.77A (3-phase) electrical_services 387 kW at 460V = 571.44A (3-phase) electrical_services 387 kW at 480V = 547.63A (3-phase) electrical_services 387 kW at 575V = 457.16A (3-phase)

Related Calculations

bolt 387,000W to amps at 400V payments 387,000W running cost cable Wire size for 657.16A at 400V (3Φ)

Frequently Asked Questions

How many amps is 387 kW at 400V?expand_more

387 kW at 400V draws about 657.16 amps on an AC three-phase circuit at PF 0.85. Alternate cases at the same voltage: 967.5A on DC, 1,138.24A on AC single-phase.

What is 387 kW in watts?expand_more

387 kW equals 387,000 watts. Multiply kilowatts by 1000.

Why do industrial systems use kW instead of watts?expand_more

Industrial equipment operates at higher power levels. 387 kW is easier to express than 387,000W. The math is identical, just scaled by 1000.

What is the formula for kW to amps?expand_more

DC: Amps = (kW × 1000) ÷ Volts. AC single-phase: Amps = (kW × 1000) ÷ (Volts × PF). AC three-phase: Amps = (kW × 1000) ÷ (Volts_L-L × √3 × PF).

Is 387 kW single-phase or three-phase?expand_more

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

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.