kW to amps Australia

Convert kW to amps on the Australian 230 V single-phase or 400 V three-phase supply and see which circuit breaker suits the load.

Inputs

Current type

Power kilowatts (kW)

Voltage volts (V)

Power factor 0 – 1

Current

Switchboard breaker for this load

How kW to amps Australia calculator works

The kW to amps Australia calculator converts kilowatts (kW) into amperes (A) on the Australian 230 V single-phase or 400 V three-phase supply with 3 inputs: power, voltage and power factor. The calculator returns the current and the next standard miniature circuit breaker (MCB) size above 125% of the current.

Power (kW)230 V or 400 VPower factor (PF)

FormulaI = P × 1000 / (230 × PF)

Current (A)Apparent power (kVA)MCB size (A)125% load (A)

5 kW at 230 V and PF 1 draws 21.74 A and suits a 32 A MCB. The same 5 kW on 400 V three phase draws 7.22 A per phase. The switchboard view highlights the MCB on a DIN rail.

kW to amps Australia formula

The kW to amps Australia formula is I(A) = P(kW) × 1,000 / (230 × PF) for single phase. There are 3 formulas for Australian supplies: 230 V single phase, 400 V three phase and MCB sizing.

230 V single phase

I = P × 1000 / (230 × PF)

3.6 kW × 1,000 / 230 V = 15.65 A

400 V three phase

I = P × 1000 / (√3 × 400 × PF)

15 kW × 1,000 / (1.732 × 400 V × 0.9) = 24.06 A

MCB sizing

MCB ≥ 1.25 × I

1.25 × 15.65 A = 19.57 A → 20 A MCB

Australia moved from 240/415 V to 230/400 V with Australian Standard AS 60038 in 2000, with a tolerance of +10% and −6%. Wiring rules for circuits come from AS/NZS 3000, and a licensed electrician sets the final breaker and cable size.

kW to amps Australia conversion chart

The kW to amps Australia conversion chart lists 13 loads from 1 kW to 30 kW with the current and MCB size at 230 V and 400 V. The chart uses a power factor of 1.

kW	230 Vamps	230 VMCB	400 V 3φamps	400 V 3φMCB
1 kW	4.35	6	1.44	6
2 kW	8.7	16	2.89	6
2.4 kW	10.43	16	3.46	6
3.6 kW	15.65	20	5.2	10
5 kW	21.74	32	7.22	10
7 kW	30.43	40	10.1	16
8 kW	34.78	50	11.55	16
10 kW	43.48	63	14.43	20
12 kW	52.17	80	17.32	25
15 kW	65.22	100	21.65	32
20 kW	86.96	125	28.87	40
25 kW	108.7	160	36.08	50
30 kW	130.43	200	43.3	63

A 2.4 kW appliance draws 10.43 A, the limit of a standard 10 A Australian power point. A 7 kW electric vehicle (EV) charger draws 30.43 A and uses a 40 A circuit.

kW to amps Australia Excel formula

The kW to amps Australia Excel formula is =A2*1000/(230*B2) with kW in A2 and power factor in B2. Use =A2*1000/(SQRT(3)*400*B2) for 400 V three-phase loads.

D2fx=ROUND(A2*1000/(B2*C2),2)

	A	B	C	D	E
1	kW	Volts	PF	Amps	Formula in D
2	3.6	230	1	15.65	=ROUND(A21000/(B2C2),2)
3	7	230	1	30.43	=ROUND(A31000/(B3C3),2)
4	15	400	0.9	24.06	=ROUND(A41000/(SQRT(3)B4*C4),2)

Add =D2*1.25 in column E to get the minimum MCB rating, then pick the next size from 6, 10, 16, 20, 25, 32, 40, 50 and 63 A.

kW to amps Australia equation

The kW to amps Australia equation is I = P × 1,000 / (230 × PF) for a 230 V single-phase circuit.

I=P×1000÷(230×PF)

I: Current in amperes (A)
P: Power in kilowatts (kW)
230: Australian nominal voltage (V)
PF: Power factor, 1 for heaters and ovens

Each kW on a 230 V circuit adds 4.35 A, and each kW on a 400 V three-phase circuit adds 1.44 A per phase.

kW to amps Australia FAQ

How many amps is 1 kW in Australia?

1 kW is 4.35 A on a 230 V single-phase circuit and 1.44 A per phase on a 400 V three-phase circuit, at a power factor of 1.

How many amps is 10 kW in Australia?

10 kW is 43.48 A at 230 V single phase and 14.43 A per phase at 400 V three phase. A 10 kW single-phase load needs a 63 A MCB.

What size breaker for a 2.4 kW appliance in Australia?

A 2.4 kW appliance needs a 16 A MCB: the appliance draws 10.43 A at 230 V and 125% of that current is 13.04 A. A standard 10 A power point supplies up to 2.3 kW at 230 V.

Is Australian voltage 230 V or 240 V?

Australian voltage is 230 V nominal under AS 60038, adopted in 2000 to replace 240 V. The allowed range is 216 V to 253 V (+10% / −6%), so many homes measure 240–250 V at the power point.