Calculator to convert watts to amperes

The transfer of watts to amperes is needed when selecting power supplies, circuit breakers and switching equipment. The fact is that often on electrical appliances manufacturers indicate either only power or only current. Therefore, you can make a translation if you use the formulas and tables that we provided in a separate article:https://our.electricianexp.com/en/kak-perevesti-ampery-v-kilovatty-i-obratno.html. An alternative is to use an online calculator that will help you quickly convert power to amperage, knowing the voltage.

We will also briefly talk about self-translation. For direct current, this expression is true:

P = U * I

According to this formula, knowing the voltage and current, you will convert them to power in watts. For alternating current, the situation is more complicated, there is full (VA), active (W) and reactive (VAR) power.

Then the formulas for the full:

Active:

P = U * I * cosФ

Reactive:

Q = U * I * sinF

Where Ф is the phase angle of voltage and current, depending on the ratio of resistive, capacitive and inductive components of the load.

To convert Watts to Amps, you need to calculate the desired value from the ratios. Here are some examples that you can avoid using the online calculator.

Let's say there is an LED strip that is powered by a voltage of 12 volts and the package claims a power of 14.4 W / m. And in power supplies for tapes, Amperes are most often indicated, not power, we need to power 3 meters of tape, then:

P = 14.4 * 3 = 43.2 W

I = P / U = 43.2 / 12 = 3.6 A

PSU must withstand at least 3.6 A. More information on how to choose a power supply for LED strip, you can find out from our article.

Another situation - you need to choose a fuse for additional halogen headlights for a bus with an on-board power supply network of 24 Volts, with a total power of 100 Watts. Then translate Watts to Amps:

I = 100/24 ​​= 4.1 A

A popular question: is it possible to connect a 5 kW 220V heat gun through an extension cord with a 16A socket and a cable of 1.5 square meters. mm:

I = 5000/220 = 22A

Answer: neither the cable nor the socket can withstand such a load.

Thus, you can determine whether the power supply, cable or socket is suitable for a certain load, otherwise you can not avoid problems and equipment failure. Our online calculator for converting watts to amperes can convert these values ​​if you indicate what power it consumes and what voltage your device is working on. This is also necessary when repairing electronics, where fuses in the power supply circuit often fail.