About

Sizing circuit breakers, conductors, and generators requires precise translation between power and current. This Kilowatts to Amps converter addresses the non-linear relationship defined by Ohm's Law and AC power theories. Unlike basic calculators, this tool accounts for system topology - Direct Current (DC), Alternating Current (AC) Single-Phase, and AC Three-Phase - and integrates the critical Power Factor variable.

Accurate amperage calculation prevents overheating wires, tripping breakers, or damaging sensitive motor windings. Electrical engineers and facility managers use these conversions to balance loads across phases and verify that installed infrastructure can handle the rated power of new machinery. The formulas implemented here adhere to standard electrical codes and physics principles.

Formulas

The calculation of current depends heavily on the electrical system type and the efficiency (Power Factor) of the load.

1. Direct Current (DC):

I = 1000 × PV

2. AC Single-Phase:

I = 1000 × PV × PF

3. AC Three-Phase (Line-to-Line Voltage):

I = 1000 × P√3 × V × PF

Where P is power in kilowatts, V is voltage in volts, and PF is the Power Factor (dimensionless ratio 0 to 1).

Reference Data

Power (kW)	Voltage (V)	System Type	Power Factor	Current (Amps)
1 kW	120 V	AC 1-Phase	0.8	10.42 A
1 kW	120 V	AC 1-Phase	1.0	8.33 A
5 kW	220 V	AC 1-Phase	0.8	28.41 A
5 kW	220 V	AC 1-Phase	0.9	25.25 A
10 kW	240 V	DC	N/A	41.67 A
10 kW	480 V	AC 3-Phase	0.8	15.04 A
15 kW	208 V	AC 3-Phase	0.9	46.26 A
20 kW	400 V	AC 3-Phase	0.85	33.96 A
30 kW	480 V	AC 3-Phase	0.8	45.11 A
50 kW	415 V	AC 3-Phase	0.8	86.95 A
75 kW	480 V	AC 3-Phase	0.9	100.22 A
100 kW	480 V	AC 3-Phase	0.8	150.36 A

Frequently Asked Questions

In AC circuits, the Power Factor (PF) represents the efficiency of the power usage. A lower PF indicates that the device requires more current to deliver the same amount of useful power (kW) because of reactive power losses. For example, a motor with a PF of 0.8 draws more current than a heater with a PF of 1.0 for the same kW rating.

You should use the Line-to-Line voltage (e.g., 400V, 415V, or 480V) rather than the Line-to-Neutral voltage. This tool uses the square root of 3 formula, which assumes Line-to-Line voltage input.

Resistive loads (heaters, incandescent lights) typically have a PF of 1.0. Inductive loads (motors, transformers) usually range between 0.7 and 0.9. If unknown, 0.8 is a common conservative estimate for sizing conductors.

Yes. While presets are provided for common voltages like 120V or 480V, you can manually enter any voltage value, making it suitable for medium and high voltage calculations (e.g., 11kV) provided the units remain consistent.