How Many Watts Does a 90 Amp Welder Use?

A question that is not much asked yet is quite important, ain’t it? Knowing the technical area of the machines you use is very essential for deciding how the procedure goes.

How Many Watts Does a 90 Amp Welder Use

90 amp welders are not widely seen today for the higher capacity ones have slowly taken over their place. But, their presence can’t be completely ruled out.

A 90 amp welder will use up to approximately 1700 watts based on the generator capacity. Some machines tend to split the watts between two outlets. In such cases, an individual outlet will supply around the same amount of watts.

I gave gathered a bit more about 90 amp welders. So let’s see what those are.

What are the capabilities of a 90 amp welder?

I have not used a 90 amp welder for a long time now. In the market also 90 amp welders are quite rare. They were once used mainly to weld thin metals.

Mostly used for stick welding, 90 amp welders are used to weld low-carbon or steel rods up to 3/16 of an inch. They might even go up to 1/8 inch if the rods are dry and new. 

As the amperage decides the penetration level of the arc, 90 amps would not be a help to weld thicker metals. The capacity to penetrate goes higher with the increase in amperage.

If you try to weld thicker metals with a 90 amp welder you are most likely to see results that are not near satisfactory. The penetration would be minimal that the process can never be carried out in the estimated time.

You will have to take more time to deal with the metal as penetration here will require more effort. One way to improve the situation is bevelling the base metal and running more than one pass into the joints.

Comparison of metal thickness penetration with higher amperage welders

90 amp welders have limited usage. They tend to lack in features and are not costly like other premium MIG welders. With higher amperage welders, the applications are more and are given higher preference.

Given below is a table that shows the maximum penetration capacity of different amperage welders on steel for two different kinds of weld:

Maximum Amps: 90 amp 110 amp 130 amp 150 amp 180 amp
Maximum steel thickness (butt weld) 2.0mm 2.5mm 3mm 4mm 5mm
Maximum steel thickness (with V and root gap) 3.0mm 3.8mm 4.5mm 6mm 7.5mm

Always ensure the specification of the machine you choose by going through the specifications sheet rather than going by the advertisement claims.

The brands might tend to up the original capacity in the ads to make the product look more promising. Yet, in charts, the correct details will be given where you can get an idea of which product to buy.

Tips and tricks to remember while welding with a 90 amp welder

1.) Optimize the speed level for the right result: The machines tend to slow down if the wire feed speed is kept low. This results in continuous sputtering of the machines and disturbs the flow of the process.

For a good weld, you need to make sure that such disturbances are kept at bay to get a good weld. From 6 and above is seen to be the ideal speed to keep the problem away.

2.) Keep the power low for a good weld profile: Maintaining the power according to your requirement is essential for a good weld profile. It is not the same power intensity that serves every time.

If you are looking to burn through metal then the power should be switched to the maximum as penetration needs the intensity at its finest form, whereas, if you are don’t want puddling up, keep the power low.

A right balance between the power and wire feed speed ensures a stable arc and hence a consistent bead.

3.) A clean metal means a clean weld: The metal you take for the base should be clean and devoid of oil or dirt. This is necessary because an unclear metal surface can lead to the spattering of the weld.

Moreover, despite the continuous weld that you manage to lay, it won’t necessarily stick to the surface of the metal.

For instance, some metals come in a form of a film on top of it. In such cases make sure to remove the coating to get a before you start welding. 

4.) Post cleanup is essential for an aesthetic look: Getting a good weld does not end with the laying of the weld. It goes beyond that.

A post clean-up using the right tool unveils the original look of the weld. You can go for different types of tools including grinders, metal brushes, wire wheels, etc. 

5.) A clean tipped torch is a handy tool: This is not necessary to be done every time you do a 90 amp welder. But, it can help you if you do it once in a while.

Remove the cone of the torch and check if there is any debris left from the previous works. Make sure you clean the inside of the torch and replace the cone. This enhances the ease of the process.

6.) Patience matters the most: Take time when you start to weld. Let the metal puddle up and slowly start laying the weld and move the gun further in a consistent motion joining the two welds.

This way, you ensure that the weld is laid aesthetically without losing its integrity. With practice, you can ace the right way to lay the weld.

Best 90 amp welders in the market

1. Chicago Electric’s 90 amp flux wire welder 

Chicago Electric’s 90 amp flux wire welder

The company being a prominent one guarantees a good welding machine that can give good welds. The company recommends a 20 amperage breaker for this machine.

From the outside, it is neat and compact so that it takes less space. However, it is not lightweight like its competitors. With a 20% duty cycle, the welder works perfectly for a 90 amperage welder. 


      • Compact
      • Good duty cycle
      • Has thermal load protection that ensures safety and prevents overheating.


      • Not lightweight
      • Power output has only two options: minimum and maximum
      • Output is only in AC and not DC

2. GCG’s 90 amp welder

Mig Welder 90 AMP Portable Welding Kit

Like the previous one, a 20 amperage breaker is recommended for this machine that runs on 120 V. The output ranges from 55 to 90 amps.

Coming with a one-year warranty this machine ensures safety and good results. This is also a flux core welder that is suited for small works.


      • Portable even when it is heavier than the usual 90 amp welders
      • Safety thermal load protection is available.


      • Not suitable for big works
      • Considerable duty cycle
      • Can only deal with low alloyed and mild steel

3. Century’s 90 amp MIG welder

Century K3493-1 90 Amp FC90 Flux Core Wire Feed Welder and Gun, 120V

The amperage range is 30-90 and this can help you weld from 18 gauge up to ¼ inch at one go according to the company’s claim.

Known for its excellent build, the welder gives quality weld results, much better than the previous two.

Weighing only 19 pounds, this is one of the most compact 90 amp welders available now. It comes with a shoulder strap which makes it even more preferable.


      • Sturdy
      • Durable
      • Lightweight
      • Portable
      • Quality built


      • Ground cable length is very short


What amperage rectifier should I use for a 90 Amp Welder?

You can go for amperage breakers up to 150 amps for a 90 amp welder. It can considerably extend the capacity of the welder.

If not 150, then a 100 will also be fine. Always try to go for the bigger ones so that the capability of the machine can be extended without the issue of overheating.

What should be the minimum voltage capacitor that I look for while buying a 90 amp welder?

As the capacitor ensures that the machine stays safe even when it is left on for days, for a 90 amp welder the minimum voltage capacitor should be 50 volts.

Does a 90 amp welder overheat fast?

No, it does not. Most of the welders available now come with enough airflow support. Therefore, there is no need to go for enhancements.

To wrap up

I went beyond the core question for two reasons. First, 90 amp welders are not used much these days, and I wanted to leave a jot for its remembrance.

Second, knowing just the watt usage of a particular welding machine is not going to help you unless you know all other aspects of it. Hope I was able to help you learn more than what you have come searching for.

Well, that is it for now. Do come back for more!

Steve Goodman
Experienced welder with 7+ years of expertise in all the latest welding techniques MIG, flux and stick welding, drill press, crane operation and metal fabrication. Welding certificate course graduate and 2018 Excellence in Welding award winner.

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