How to convert 3 amps to watts

How to convert electric current of 3 amps (A) to electric power in watts (W).

You can calculate (but not convert) the watts from amps and volts:

For DC power supply, watts are equal to amps times volts.

watts = amps × volts

watts = 3A × 12V = 36W

For AC power supply, watts are equal to the power factor times amps times volts.

watts = PF × amps × volts

For resistive load without inductors or capacitors, the power factor is equal to 1:

watts = 1 × 3A × 120V = 360W

For inductive load (like induction motor), the power factor can be approximately equal to 0.8:

watts = 0.8 × 3A × 120V = 288W

For AC power supply, watts are equal to the power factor times amps times volts.

watts = PF × amps × volts

For resistive load without inductors or capacitors, the power factor is equal to 1:

watts = 1 × 3A × 230V = 690W

For inductive load (like induction motor), the power factor can be approximately equal to 0.8:

watts = 0.8 × 3A × 230V = 552W

See also