Welding Machine Wattage

Welding Machine Wattage

If you’re shopping around for the best welding machine, you may have noticed that there are several different wattage options available on the market.

While you may know what wattage means in general, do you know how it pertains to your specific needs? How much wattage do you need? What wattage would be overkill and cost more than necessary?

If you’re trying to welding machine wattages, this guide is for you.

Understanding Welding Machine Power Requirements

Several factors can help you understand the power requirements for welding machines.

If you do not know what these factors are, you will have difficulty knowing how much power your machine needs.

To ensure that you get enough power for your welding machine, it is best to consult an expert first.

Welding machine wattage requirements will depend on various factors, including amperage voltage. The higher your amperage, the more power your welding machine will need to keep up with it.

What is the function of wattage on a welding machine?

In order to understand what welding machine wattage is, you must first understand what a welding machine is.

A welding machine, also known as a welder or, more colloquially, a welder’s torch, is any piece of equipment that uses an electric arc between two consumable contacts called electrodes to generate heat and apply it to workpieces to fuse them together.

The electricity passes through one of these pieces of metal or wire-like rod called filler material or an electrode, which in turn melts at certain temperatures (depending on their composition).

Welding Machine

So that when it touches another electrode attached to another piece of metal that melts at lower temperatures.

It causes an electric arc that passes through said filler material, heating it up even further until both are melted into one unit.

Therefore, if you want to know what welding machine wattage is, the amount of energy goes through said filler material or electrodes that causes heat for said melting to occur. It is measured in watts (W).

Now, let’s move on to power consumption which is essentially how much electricity a piece of equipment consumes at any given time.

In order to understand power consumption, we must first understand voltage which can be thought of as pressure or tension in an electrical circuit.

In contrast, current can be thought of as flow rate or volume in an electrical circuit (the two are always inversely proportional).

Voltage and current are measured in volts and amps, respectively. Power consumption is usually expressed in watts because it relates to energy over time: 

P = IV


P stands for power,

“I” stands for current, and

“V” stands for voltage.

What to know before determining Wattage?

In order to understand how much Power/Wattage each welder uses, one must look at three aspects of welding.


The first is amperage. Amperage measures how much electrical current a machine draws in an hour or other time.

For example, if you have a 240-volt machine that draws 120 amps while welding, it will draw 28,800 watts or 28.8 kilowatts.


The second aspect is voltage. Voltage tells us how many electrons are pushed through a wire for every unit of charge that flows past a given point.

For example, if you have a 12-volt machine, it will push 12 volts of electricity through each wire. A 120-volt machine will push 120 volts; 240 volts will push 240 volts; 480 volts will push 480 volts, etc.

However, one more thing to note. People often ask the following types of questions.

  • What is 250 amp welding machine wattage
  • What is 300 amp welding machine wattage
  • Tell me 3 phase welding machine wattage etc.

You should know that only the current flow or phase number cannot decide the wattage. There is more information that is needed to calculate them. But often, manufacturers fix some values. But that is not the topic of today.

How to Calculate Wattage of Welding Machine?

Wattage measures how much power (measured in watts) each machine uses to perform work.

For example, if you have a 20-amp, 125-volt welder that draws 20 amps while welding, then the maximum wattage will be 2500 watts.

It is important to note that some machines have maximum wattage ratings as well as minimum ratings.

In these cases, you must make sure your power supply can handle all of your equipment’s needs plus any additional electrical loads in your workshop.

Some welders also offer different power settings for different types of metals. These settings are usually listed in amps—for example, 10/15/20 amps means there are three separate settings:

  • 10 amps for thin metal sheets,
  • 15 for general-purpose metal, and
  • 20 for thicker metals.

Final Thought

Always remember that more powerful units will be able to tackle more complicated jobs than less powerful ones.

And keep in mind that when shopping around, price tends to correlate with both size and power and get the perfect welding machine for you.

As an added bonus, larger machines tend to cost less per amp hour than smaller ones.

When buying your first welder, it’s a good idea to stick with one that runs off household current (as opposed to industrial current).

This will allow you to use cheaper extension cords and fit into most standard electrical outlets without issue.

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