What Size Generator to Run a 140 Amp Welder
There are dozens of reasons why you might want to power your welder with a generator. You might want the flexibility to use the welder outdoors. Or you might not have a reliable electricity connection in your workshop. Alternatively, using a generator for power tools can reduce your electricity bill.
Regardless of the reason, many people prefer to power welders with a generator. The only problem is trying to decide how powerful the generator should be. Here’s how to calculate how much electricity is needed to run a 140-amp welder.
Finding the Number of Watts Your Welder Uses When Running
The output of many generators will be expressed in watts. To find one that provides the right amount of power, we will need to find the number of watts your welder is using. To do this, you will need to do a little maths. Don’t worry, though, it’s a simple calculation.
To find the required wattage, you will need to know two figures. First, you will need to know the amps. This is a measure of the electrical current. Then, you will need the voltage. This tells you how much pressure is in the circuit.
Both of these figures should be found in the owner’s manual or in the technical specifications on the manufacturer’s website. Sometimes, the voltage will vary, depending on the type of weld you are making. Because of this, it might be listed in a range. For this calculation, we want to take the top figure of the range.
Then, simply multiply the number of volts by the number of amps. This tells you how many watts the generator will need to be to power the welder when running. For example, if you had a 140-amp welder that requires 20 volts, you would need a generator wattage of 2,800. If you prefer, you can plug the figures into this calculator.
However, there is another element that you will need to consider. When the welder is just starting up, it will require more power. To factor this in, it’s best to add 30 percent to the running power. Returning to our example, 30 percent of 2,800 is 840. As a result, you’ll need a generator that can produce at least 3,640 watts.
As a general rule, though, most 140-amp welders will require a generator of 3,600 to 4,500 watts to run. When in doubt, though, it’s best to get a little more power than you need. This will give you the option of running additional appliances, like another tool or a light.
Finding How Many Watts Your Generator Provides
The next step is to find out how many watts your generator will be able to provide. The good news is that this should be fairly easy. In most cases, the watts should be printed on the generator or listed in the product specifications. It’s possible that it might be listed in kW (kilowatts). A kilowatt is simply 1,000 watts.
At other times, you will find that the generator is measured in kVA. This article goes into more detail about how a kVA is different from a kW. However, for our purposes, the more important element is knowing how to covert kVA to watts. All you need to do is multiple the kVA number by 800 to get the number of watts the generator will be producing. For example, a 5kVA generator will produce 4,000 watts.
Other Tips to Find a Quality Generator
Knowing the number of watts your generator can produce is important. But there are some other elements that you should consider when trying to find the right generator for a 140-amp welder.
Deciding Between Inverter and Conventional
There are two types of generators you can choose from, either an inverter or a conventional generator. The key difference is the way that they produce electricity. Conventional generators will send the power straight from the engines. This can cause minor fluctuations, which have the potential to damage sensitive electronic devices.
Inverters will refine the electricity before they release it. It will be produced in DC, then converted to AC, which electronic devices need to run. Because of this, you can expect a smoother current. This article goes into more depth about the differences between the two generator types.
However, when powering a welder, it’s usually best to use a conventional generator. Inverter models tend to be more expensive. Plus, you might struggle to find one that will be able to produce enough electricity to run a welder.
Runtime
If you are planning on using the generator for complex welding projects. You need to get something that will last for a long time. The runtime will often depend on a few factors, like the size of the gas tank and the load being placed on the engine. It’s also important to consider the type of fuel you are using. Petrol or diesel generators will require you to stop, wait for the generator to cool down, then fuel up the tank. If you are using propane, you can connect multiple tanks to a stopcock valve.
Larger generators should be able to run for hours, lasting for a whole day. Smaller models can typically run for a few hours before you need to give them a break.
Build Quality
Lastly, you should choose a generator that has been built to last for a long time. There are a few things you should be looking for. First, it’s important to pick something from a respected manufacturer. It’s also a good idea to read through the reviews to find something that customers respect. If you are looking for a place to start your search, check out this compilation of high-quality generators.
Last Words
If you are planning on buying a generator, you need to make sure that it has enough power to do the job. When it comes to running a 140-amp welder, this usually means finding something that will be able to produce between 2,800 to 4,500 watts.