Can someone explain mig duty cycles?

I want to plug this in to the appropriate power supply and want to know what this draws. The ratings are throwing me off from my basic understanding of electricity.

I have read that a duty cycle for welding is the period of time per 10 minutes that a welder can run before it over heats. So my guess for this welder is that it can run for 2 minutes straight before it quits or trips the breaker?

Here is the mig welder my buddy has:
Airgas - **Miller® Millermatic® 135 MIG Welder 115 Volt, 1 Phase, 60 Hertz (Liquidation Sale - While Supplies Last)


I was planning on putting in a single outlet 20amp outlet from a 20 amp breaker on the main panel (12/2). Is this adequate?

Thanks!

I should know this, since I took a class on it.

I have a similar machine, and it can go about 2 minutes straight a full power with a 20 amp breaker. I've never timed it, I just get annoyed and walk away.

Go to Miller's website and download the manual. They are under the "Resources" tab at the top of the page. It will tell you what breaker to use as well as the welder's duty cycle. Duty cycle is a rating at a specific amperage. For that model, it is rated at 20% duty cycle at 90 amps, meaning that you can weld for 2 minutes at 90 amps before the welder cuts output so that it can cool. At 40 amps you can weld continuously, all day. The manual has a handy graph to let you know how long you can weld at a specific amperage.

Duty cycle does not indicate what breaker to get.

phoenixs4r said:

I should know this, since I took a class on it.

I have a similar machine, and it can go about 2 minutes straight a full power with a 20 amp breaker. I've never timed it, I just get annoyed and walk away.

Click to expand...

Not exactly true. That welder can only go 1 minute at full power (135 amps) before it overheats. At 90 amps it will go 2 minutes. It's all in the graph in section 3-2, page 10.

so I am running at wire speed 60 and voltage control 10 on the 115vmodel... consulting the manual...

So I guess I don't understand how I determine the output ampheres that I will be using.

Well, I just studied the manual and I have no idea how to determine the output amps, either. It doesn't tell you. What was your original question? What breaker to get? That is independent of output amps.

What exactly are you trying to determine now? How long to weld before you should stop to let it cool? I say just weld what you need to at the settings they need to be at to make a good weld. IF you over heat it, take note and try not to weld for that long on those settings again.

So, again, what exactly is your question?

I wanted to be sure that my breaker was big enough to handle everything for usage. I am really only interested in how many amps this unit wants for input, which looks like 15-20 from the spec sheet so I should be all good with my wiring.

However knowing the how to determine output would be handy since that would tell me the in place duty cycle to observe.