Perhaps you’re now a proud owner of a washing machine or water bed that uses 480 watts. Now, you’re wondering how to convert 480 watts to amps.
Converting any wattage rating to amps typically uses the formula: Amp = Watt / Volt. So, if a 480-watt appliance uses 120 volts, the amperage is 4 amps.
Note that depending on the circuit, you may need to use other formulas. In particular, use a different formula if the electronic device runs a DC, AC single-phase, or three-phase current.
Table of Contents
Calculating Amps from Watts
As mentioned earlier, the formula to figure out amps from watts depends on the current type. In this section, you’ll learn the formulas to use for each of the general currents you can encounter.
1. Watts to Amps Using DC
The formula to use when finding out amps from watts and voltage in DC is the following:
\begin{equation}
Amp = \frac{Watt}{Volt}
\end{equation}
Example:
\begin{equation}
Amp = \frac{480w}{240v} = 2a
\end{equation}
2. Watts to Amps Using Single-Phase AC
A single-phase AC alters the power’s supply voltage alters simultaneously. Also, it uses the following formula to find the amperage:
\begin{equation}
Amp = \frac{Watt}{Power Factor (PF) \times Volt}
\end{equation}
wherein PF is equal to 1
Example:
\begin{equation}
Amp = \frac{480w}{(1 \times 12v)} = 40 \text{ amps}
\end{equation}
3. Watts to Amps Using Three-Phase AC
Three-phase AC is often more efficient than single-phase AC, thanks to its three electric services. Find out the amps of a three-phase AC using the following formula:
\begin{equation}
Amp = \frac{Watt}{\sqrt{3} \times PF \times Volt_{\text{line-to-line connection}}}
\end{equation}
Example:
\begin{equation}
Amp = \frac{480w}{1.73 \times 1 \times 220v} = 1.26 \text{ amps}
\end{equation}
Aside from using the formulas above, you can also use an online amperage calculator. Some calculators can also help you calculate for different current types, including single- and three-phase AC currents.
Frequently Asked Questions
How many amps are 480 volts?
Use the formula mentioned earlier for this concern. Also, assuming the device uses 480 watts, the unit draws 1 amp.
How many watts are in 1 amp?
It depends on the voltage at which the ampere (amp) is measured. Watts is the unit of power, while amperes (amps) are the unit of electric current.
The formula defines the relationship between watts, amps, and voltage:
\begin{equation}
\text{Power (in watts)} = \text{Voltage (in volts)} \times \text{Current (in amps)}
\end{equation}
So, to calculate the watts in 1 amp, you need to know the voltage.
A standard household electrical system in the United States operates at 120 volts, then:
\begin{equation}
\text{Power (in watts)} = 120 \text{ volts} \times 1 \text{ amp} = 120 \text{ watts}
\end{equation}
Conclusion
Remember, figure out the current type before converting 480 watts to amps. Use the wrong formula, and you’ll likely get inaccurate results. Using the wrong values in an electrical wiring setup may result in various issues.
For example, if you’re looking for the amperage of a 480-watt appliance at 360 volts in DC, the answer is 1.3 amps. But you can skip the guesswork using an online amperage calculator, especially one with various current settings.
I am Andrew Wright. With 8 years of experience designing, installing, and maintaining electrical power systems. I love my job, and I have always wanted to offer others the necessary help so they can take care of their houses.