What Size Generator For Welder?

What Size Generator For Welder

Welding is a process that entirely needs a power supply to operate. If there is no source of power, then you cannot be able to weld. But what if you are in a remote area where there is no power supply?

With the advance in modern technology, manufacturers have come up with welders that are compatible with generators. Nonetheless, you will need to know what size generator for welders you require.

What is a Welder Generator?

A welder generator is an equipment that supplies power to a welder without the need for electricity from a main power source. They are usually convenient and can be useful in any place where the power supply is limited. Moreover, they are easy to operate. Like the other standard generators, you only need to fill its tank with fuel, turn it on, and boom!

Besides using it for welding, you can comfortably use it to power other devices and power backup, too, thus being reliable. Therefore, if you are a professional welder, you may consider investing in a welder generator to avoid power interruptions during welding.

How does a Welder Generator work?

You may be thinking about whether a welder generator works the same way as the standard generator. The answer is yes, it does, in most instances. The most common is that you need to add fuel to their tanks to operate. The difference may come in the amperage and voltage needs.

The first thing to do is ensure your welder generator’s tank has fuel if it runs on fuel because some use oil. If it is low on power, add more. You can then start the generator.

Each welder generator has its way of starting it up, either by pulling a string or using an electric start, whichever you find comfortable for you.

Connecting your welder to the outlet located on the side of the welder generator comes next. You should make sure that the plug is compatible with that of the generator. Those generators that have a ready welding kit are preferably the best.

You now need to take control of the welding process by adjusting the coarse and refined settings. The coarse setting helps increase the amperes and voltage, while the fine minimizes the two depending on the welding job. The moment you are through, switch off the welder generator to save on fuel and avoid any dangerous hazards.

Advantages of a Welder Generator


You can easily carry welder generators in your car and go welding in a remote place or on your farm. This is one of its most significant advantages. Though others may be heavy and light, it will zero down to your preference. Light welder generators offer more mobility than heavy ones.

No power interruption

Using a welder generator allows you room to continuously weld without any power interruption, unlike when you depend on the mains electricity. It is a good source of power backup altogether. At this juncture, you should get a good build and quality generator that will not overheat when running continuously. A generator that constitutes heavy-duty parts will not behave in that manner.


Besides being used for welding, it can also work as a stand-alone generator. This means it can provide power backup to your other appliances aside from welding.

This saves you the money that you would have otherwise spent on buying another generator. It saves you a lot of time as it can do more than one job at once, provided it has the right voltage and amperage.


Generally, welder generators generate more power because of the intense power needed for welding. For this reason, manufacturers equip these generators with high amps and excellent voltage output to deliver outstanding results, unlike the standard generators.

What size generator for a welder?

Now we need to determine the right size of the generator for welding. This mainly depends on the magnitude of the job you are doing and the welding location in some instances. Also, are you going to use your welder generator for other equipment such as compressor and power backup? But again, it is safe to invest in a big generator rather than a small one.

The two main things to look at are voltage and amperes. The standard amperes a welder generator needs are 30. Multiplying voltage and amperes enables you to gauge your generator’s output with watts measurements.

There are running watts that indicate the outcome of the generator while it’s running. Start-up watt rating is what occurs when the generator experiences a minimal spike when it starts. It is usually more than the running watts.

Some generators have their watts labeled on them. It is essential to find out whether it is the running or starting watt rating. Once you know how much power your welder can draw, you will determine the generator’s right size for you.

To find the output of your welder, find out its amperes and multiply by its voltage. You can use the manufacturer’s information on the generator too. If your welder has a wattage rating of 3000W and below, then it can comfortably be powered by a generator with a wattage of either 5000W or 3000W.

A 5000W and below welder operates on a 5000W generator. Anything higher than this will require you to use a generator with a wattage rating higher than 5000W.

If your welder’s input voltage is 120V while the output is 30Amps, then multiply the two to get its wattage, which is 3600W. So, if your welder generator has a higher watt rating than this, it will be able to run the welder.

Final Words

Getting to know what size generator is for a welder is essential in the whole welding process. If you are not using mains electricity, then you will need a generator.

And you cannot just use any size generator on any welder size. Determining the correct size improves the performance of both the welder generator and the welder machine.