Welders Galore

Welders Galore

Inverter vs Transformer Welder-Which is Best for the Job

There have been electric welding machines in use for over 100 years, but recent advances in technology have led to an inverter vs transformer welder conundrum. Both machines have clear advantages and disadvantages for new and professional welders alike. Choosing the right machine will be determined by your own preferences and the task at hand. In this article, we will take a closer look at to help you make an informed purchasing decision.

What is a Transformer Welder

Inverter vs transformer Welder

A transformer welder is a conventional machine that is a workhorse in the welding industry. This machine requires mains power, it’s typically used for industrial rod welding, and it comes in a range of sizes from 250A up to 600A working at 415v. The welder can adjust the output voltage by tapping the secondary transformer winding. The output current is adjusted by moving the winding closer or further away from the secondary winding.

Another approach is to move the magnetic shunt in or out of the transformer core with a series saturating reactor to alter the approach with the secondary current output. A transformer welder is a cost-effective machine, they are found in many welding applications that use ferric metal compounds, including sheet connections, metallic structure attachments, plumbing pipelines, and the laying and repairing of pipelines.

Pros and Cons of a Transformer Welder


  • Initial purchasing costs are lower.
  • This welding machine is maintenance free.
  • Running expenses are affordable.
  • A great option for farm repairs.
  • A reliable welding machine.


  • This welding machine is prone to sensitivity during voltage reduction.
  • It can be a challenge to ignite the arc.

What Is An Inverter Welder?

Inverter welder

In the inverter welder vs transformer welder debate, it’s important to understand the key differences. The main difference is that an inverter welder converts AC to a lower voltage output that is usable, such as 240AC down to 20v DC power output. To make this change an inverter welder and other such appliances have dedicated electronic components.

A traditional transformer based welding machine relies on a single larger transformer to control the voltage safely. Changes are made with simple buttons that switch the power on and off at one millionth of a second. This control protects the power supply and the size of the transformer can be much smaller.

An inverter welder can gather power quickly using any gate current due to the insulated bipolar transistor technology. The switch operates at high speeds which consume less energy in normal operations. The minimal design allows the user to operate the machine in almost any location when compared to other welders. These machines are compact, they are easy to transport and the weight is significantly lessened.

Pros and Cons of An Inverter Welder


  • The electric arc is easier to control.
  • This is a highly portable welding machine.
  • A cooling fan is installed to protect components against the heat.
  • The power consumption is low.


  • The repair costs can be expensive.
  • This is a less durable machine when compared to conventional transformer models.

Inverter Vs Transformer Welder Features

 Inverter WelderTransformer Welder
Available Sizes100A to 270A @ 240v250A to 600A @ 415v
MaterialsVariousMild steel
LocationBest in indoor worksitesIndoors or outdoors
PortabilityYesNot as easy

Which Is Better-Inverter Or Transformer Welder

This is a hard question to answer because people have different needs and these machines have certain factors to consider, such as:

Permanence of the Welders

Transformer welding machines have higher duty cycles which allow the operator to tackle heavy-duty tasks more efficiently than inverter machines. The durability of a transformer machine is well known and inverters are an unknown quantity because they are newer. But, inverter technology is compelling because a lot of power can be packed into a smaller format.

Weld Quality

If you’re a welder that handles placid steel regularly you can rely on a transformer welding machine. But, for those seeking welding perfection on a variety of materials, an inverter welder can be a good option. These machines can be programmed for a wide variety of applications with pulse MIG that’s similar to TIG.

Improved electronics and software have opened up new welding machine capabilities that can improve the overall results. For the best quality and true innovation, an inverter welder is the best choice and you can make simple steel welds too.

Duty Cycle of the Inverter vs transformer Welder

An inverter welder can achieve higher duty cycles because of the transformer size. The smaller components can heat up quickly, but they cool down faster than traditional welders which are larger and retain the heat for longer

Generator Power of the Welder

One of the main considerations for remote work in the inverter welder vs transformer welder choice is the use of generator power. This is more possible when you’re using an inverter machine which can run on a small portable generator unit. Using conventional transformer welding machines with a generator is possible but there are safety concerns.

Costs of the Different Welders

A transformer welder is a budget friendly option, but over the long-term an inverter tends to save the operator more money. An inverter welder consumes less energy and some professionals estimate savings of 10% on their power bills. Inverter welders use less consumables and the arc stability is impressive.

Weight of the Welders

Inverter welders are lightweight and portable and they can be half the size of an equivalent transformer machine. So, if you need a machine to weld on the go it makes more sense to purchase an inverter machine.

Welder Stability

Transformer welders have evolved significantly in the last 50 years and they are an efficient option with no loss of stability in the arc. But, most inverter welders are at least twice as effective as a traditional transformer welder. Around half the amperes are required to get the same volts and you can run an inverter from a standard home power outlet.

The earlier inverter machines used DC, they had a stable arc than DC transformer machines but only a single AC option was available. Modern inverter machines use both DC and AC and they are extremely effective with a stable arc. At the moment the best combination of effectiveness and stability is a good quality inverter welding machine.

Welder Functionality

A high-quality inverter welder is superior to a transformer machine and this is especially true with MMA or stick welding. Experienced operators appreciate that they don’t need to “fight the arc”. This is because an inverter welder has higher open circuit voltages with useful integrated features, such as: Hot Start, Arc Force and Anti-Stick.

These features are helpful when slim materials are welded which would be impractical with a transformer machine. Inverter welders have limitless amperage adjustment options and a stable arc. The power can be reduced to weld thin sheets of metal or sections of pipe together in a controlled manner.

ConclusionInverter vs transformer Welder

Over the past decade, the inverter vs transformer welder choice has become easier because inverter machines have improved and they have become more affordable. A transformer welder can be a great option for static locations when upfront costs need to be kept low. The exact choice that you make will be ultimately determined by your needs and other factors related to how you use your welding machine.

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