What's the minimum breaker I need for a 110 amp 220v arc welder?

Generally these will work from a 20 amp 110VAC outlet. The welders have a transformer to take 110VAC 20 amp to something like 110 amps at 20 volts.

If you don't have a 20 amp circuit in your shop, just add one, wire it with 12 ga wire. You can get a 20 amp GFI outlet if you look around, rather than the usual 15 amp GFI outlet. GFI is required by code for general outlets in many cases, such as garages. Use a 20 amp outlet in any event.

Richard

Michael Shaffer wrote:

I just bought a 110 amp 220v arc welder, does this mean I need a 110+ amp circuit breaker?

Depends, but most likely only a 50 amp CB.

The infamous Lincoln 225 amp "Lincwelder" takes a 50 amp CB.

The reason is a "buzz box" contains a transfomer, which reduces the 240 volt input to something like 70 volts, open circuit, and perhps somewhat less than that after the arc is struck.

Let's say the voltage is 50 after the arc was struck. Then the current would be

50/240 (the transformation ratio, under load) of the maximum rating of the welder (225 amps), which result is 47 amps.

Now, the "duty cycle" of your welder may be only 20 percent, in which case you could install an 8 AWG feeder and a 50 amp breaker. If the duty cycle was significantly higher, then a 6 AWG feeder would be required.

Since my welder's feeder was so short, I installed a 6 AWG copper feeder, and a

60 amp CB.

First off, it is most likely the output amperage that's 110A, not the input amperage. Even if it is the input amperage (which would mean you have a big-ass welder, weighing several hundred pounds) you can still get by on a smaller circuit unless you set it to its highest amperage. If you have a 50A circuit now, use it. If the breaker pops, then you have the choice to turn the welder down (use lower amperage) or put in a larger breaker. I've often wondered if you could put in a few run caps to make the (largely inductive) load look more resistive, which might allow you to get more output.

If this is a little buzzbox, it will run on a 15A circuit easily. If it's at all new, it likely says what the input amperage is on the case, somewhere near the power cable.

GWE

Michael Shaffer wrote:

Here's the auction

I guess that's a buzzbox? Will this be powerful enough to weld two peices of 2.5" diameter exhaust pipe together?

Grant Erw> First off, it is most likely the output amperage that's 110A, not the

50 amp breaker is fine and yes..it will have more than enough power. Too much in fact if you are like me..a novice welder.

Gunner

No 220-pound thug can threaten the well-being or dignity of a 110-pound woman who has two pounds of iron to even things out. Is that evil? Is that wrong? People who object to weapons aren't abolishing violence, they're begging for the rule of brute force, when the biggest, strongest animals among men were always automatically "right". Guns end that, and social democracy is a hollow farce without an armed populace to make it work. - L. Neil Smith

Even though the auction says "230v @ 110a" it's really 110a _output_. For which a 50a breaker is optimum. I run my 225a Lincoln on a 30a breaker 'cause I don't use the higher amps ever (120a occasionally).

The minimum amperage on your welder is 45, which is pretty high for tailpipe. Tailpipe is a very challenging weld even with a lower amperage. Burn through is the problem.

Bob

BTW - I Googled "Buffalo arc welder" and got the toolsteal site. The welder msrp is $65.99, but they have it on sale for $69.30!! Some "sale".

Whoops! I misread the question, for a 220V welder, 50 amps is the right breaker size, with 8 ga wire.

Richard

Richard Fergus> Generally these will work from a 20 amp 110VAC outlet. The welders have

A stick welder nomally has a welding voltge around 20 to 25 volts or a 10:1 reduction from the 240 volt input line. But the current increases by a like amount. This unit should run on most any 240 volt circuit, 15 amp or 20 AC circuit would work, 30 amp dryer circuit would be great.

This unit has a top power of 110 amps, about the minimum to run

1/8" rod. It should be f> Here's the auction

If you are in England that would be 230 volts, 50 Hz. However, if you are in North America, then it is 240 volts, 60 Hz.

The 110 amps will be the secondary current. The primary side current will likely be 1/4 of that or around 30 amps max. If it is a fairly recent welder it should have a capacitor inside to correct the phase angle somewhat, which helps to minimise the current draw at max amps.