kW to Amps Calculator – 415V Three Phase

Q: How do I convert kW to amps on a 415V three phase system?

I = (kW × 1000) ÷ (√3 × 415 × PF) = (kW × 1000) ÷ (718.77 × PF). For 10 kW at PF=0.85: I = 10,000 ÷ (718.77 × 0.85) = 10,000 ÷ 610.95 = 16.37 A.

Q: What is 415V used for?

415V line-to-line (240V phase-to-neutral) is the standard three phase voltage in the UK, Australia, India, New Zealand, South Africa, and most countries using IEC standards. It is used for industrial motors, commercial HVAC, and high-power equipment.

Q: Is 415V the same as 400V?

They are close but not identical. 415V is the traditional UK/Australia standard; 400V is the EU/continental European standard. After IEC harmonisation, many countries have moved toward 400V, but 415V installations remain common, especially in older buildings. Always check equipment nameplates.

Convert kilowatts to amps for 415V three phase systems. Standard for UK, Australia, India, and IEC countries. Enter power and power factor to find line current.

This calculator provides estimates only. Always consult a qualified electrician for real installations.

kW to Amps (415V, Three Phase)

Power (kW)

Line Voltage (V)

Power Factor

Result

—

Line Current (Amps)

—

Apparent Power (kVA)

Formula for 415V Three Phase

I = (kW × 1000) ÷ (√3 × 415 × PF)
I = (kW × 1000) ÷ (718.8 × PF)

Where √3 × 415 = 718.77. At PF = 0.85: I = kW × 1.636 A per kW

Quick Reference Table – 415V, PF = 0.85

Power (kW)	Current (A)	kVA
5 kW	8.18 A	5.88 kVA
10 kW	16.37 A	11.76 kVA
15 kW	24.55 A	17.65 kVA
22 kW	36.01 A	25.88 kVA
30 kW	49.1 A	35.29 kVA
45 kW	73.6 A	52.94 kVA
75 kW	122.8 A	88.24 kVA
110 kW	180.1 A	129.4 kVA

About 415V Systems

415V line-to-line corresponds to 240V phase-to-neutral in a three phase star (wye) configuration. This is the standard supply voltage in the UK, Australia, New Zealand, India, South Africa, and most other IEC-standard countries.

Equipment rated for 415V (UK/AUS) can usually operate at 400V (EU) — check nameplate tolerances.
Phase voltage is 415 ÷ √3 = 240V — the same as single phase supply voltage in these countries.
Use line-to-line voltage (415V) in three phase current formulas, never phase voltage.
For motor selection, use 125% of full-load current for cable and protection sizing.

Frequently Asked Questions

How do I convert kW to amps on a 415V three phase system?

I = (kW × 1000) ÷ (1.732 × 415 × PF) = (kW × 1000) ÷ (718.8 × PF). At PF = 0.85, this simplifies to approximately I = kW × 1.636. For 22 kW: I = 22 × 1.636 = 36 A. This is the line current — each phase conductor must carry this current.

What is 415V used for?

415V three phase is used for industrial and commercial applications: motors, compressors, pumps, commercial HVAC, manufacturing equipment, workshop machinery, and large commercial buildings. Standard consumer supply in UK/AUS is single phase 230V (from one phase to neutral of the 415V three phase system).

Is 415V the same as 400V?

Not exactly — 415V is the traditional UK/Australian/Indian standard, while 400V is the EU/European standard following IEC harmonisation. Most modern equipment rated for 400V works fine at 415V and vice versa (within ±10% tolerance). For precise calculations, use the actual nameplate voltage of your supply and equipment.