Converting kW to Amps for DC, Single-Phase and Three-Phase.
If you’re sizing cables or designing power systems, these formulas are essential.
DC
I = (P x 1000)/V
Examples
DC: 2 kW at 48 V. → 41.7 A
Single-Phase AC
I = (P x 1000)/(V x PF)
Example
Single-Phase AC: 5 kW at 230 V, PF = 0.9 I = (P x 1000)/(V x PF)
Three-Phase AC
I = (P x 1000)/(√3 x V x PF)
Examples
Three-Phase AC: 10 kW at 400 V. PF = 0 l = (P x 1000)/ (√3 x V x PF)
85-17.0 A
Higher voltage = lower current for the same power.
It is the reason that high-voltage systems are more efficient for transmission and distribution.
How many kW is 20 amps?
Given
Amps = 20 A,
Solution
Standard Voltage = 240V,
Standard Power Factor = 0.8
kW = (20 × 240 × 0.8) / 1000
kW = 3840 / 1000 = 3.84 kW
Answer
kW = 3.84 kW