arc welding with generator

I would like to start practicing with an arc welder on scrap metal so I
can move on to welding up metal buildings. The problem is, there is no
electric where I need to practice my welding. I do have a 5500 watt
generator with 9500 surge. I'd like to buy a buzz box to start arc
welding, but I don't want to destroy my generator either for drawing
too much current. Do you guys have any estimates as to how many amps I
can go up to on a buzz box and stay under 5500 watts from the
generator? I'm looking at the 225 amp AC buzz box.
Thanks,
Sam
Reply to
Rancher Sam
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If you need to practice with an arc welder before welding structural steel for a building, you might want to take some welding classes first. The life you save might be your own.
Buildings that are large enough to need welding don't always have electric service on site either. You might want to look into an engine driven welder, perhaps rent one on a per job basis.
Your generator does not have enough surge capacity for a 225 amp AC buzz box. My 225 amp 240 volt 1ph buzz box trips a 50 amp circuit breaker about once every tenth time I click the switch to turn it on. It takes an enourmous surge current to saturate a large transformer -- my guess around 100 amps. The circuit breaker doesn't trip every time because there is a delayed trip mechanism to account for surge currents, but it still does trip occasionally. The manufacturer recommends a 50 Amp circuit breaker, so that is what I have. Installing a larger circuit breaker would void my insurance policies.
The maximum surge current on your generator is 9500/240 = 40 Amps. which is less than the 50 Amp circuit breaker I have.
Reply to
Speechless
Your genny is not nearly enough to run your buzzbox.
If you're talking about welding sheetmetal up to 5/16" steel, I'd recommend that you consider a wirefeed welder. You can run fluxcore outdoors. Wirefeed draws a lot less mains current for given welding current than stick because it has considerably lower open circuit voltage (and therefore higher transformation ratio) than a buzzbox. For example, a Hobart Handler 180 draws 20 amps of 220, which your genny should be able to deliver without any problem.
Reply to
Don Foreman
Thanks for the replies. I was wondering if I can run a 225 amp buzz box at less than its full amperage. The lincoln 225 ac that's in most home improvement stores has a selector knob that allows you to go from say 60 amps all the way to 225. If I run the buzz box at 150, for example, can my 5500 generator handle that?
I have a lincoln, weldpak 3200, mig welder that's for up metal up to 5/16s. Can I make structural welds with multiple passes using this?
Thanks for all the info.
Sam
Reply to
Rancher Sam
The Lincoln buzz box runs at about 25 volts while welding. If your generator can really put out 5500 continuous, that works out to 220 amps. Allowing for some losses, I'd guess that you could run the 175 amp tap with no problem. This would be enough to run 5/32" 6011 rod
Your 9500 watt surge works out to a 40 amp surge capability, should be enough if you stick the rod.
I run an older AIRCO 225 amp welder on a 4000 watt el cheapo generator. I keep the weld current down to 120 amps, enough for 1/8" rod. Tends to be a bit finiky but works ok.
Rancher Sam wrote:
Reply to
RoyJ
I wouldn't. 5/16" is really pushing the 110-volt boxes. I think 1/4" is pushing them, though it can be done -- but you'd spend 90% of your time waiting for it to cool down after every few inches of weld. (Been there, done that) You'd be OK with a 220-volt 180-amp wirefeed machine if you're a good weldor. As long as you have a puddle in (not just on) the parent metal, you're welding.
Buzzboxes draw pretty heavy current even at the lower amperage settings. It's low power factor inductive current so it doesn't spin the meter, but it can still overload a genny.
Reply to
Don Foreman
No. Look at the V-A curves for buzzboxes. The OCV is about 80 volts, indicating a transformation ratio of about 0.364 : 1. Inductive impedance in the welder reduces the arc voltage to about 25 volts, but the current ratio will still be about 0.364 : 1, which means about 45 amps of line current at 125 amps of arc current. The genny is rated in watts to resistive loads like lighting, but it's limitation is really current.
Transformation ratio changes some at the higher current taps. OCV is lower on them. So the welder might run on a 50 amp breaker at higher arc currents, but the line current doesn't diminish much at lower arc currents.
Further, a genny has a lot less patience than a circuit breaker. You can run a 50 amp breaker at 25% overload for quite a while before it trips, but that isn't true of a genny.
Reply to
Don Foreman
Click on this (IT WILL TAKE A MINUTE TO LOAD)
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to here the load a 1/8 7018 rod puts on a 12 HP Briggs running an alternator welder. 12 HP is about the cut off point. Now this is NOT a buzz box on a gen. Its a belt driven car alternator working its ass off. The sample in the photo are poor, I have done some real nice welds with this set up.
Reply to
wayne mak
Frankly..Id go with the Lincoln, using a wire called Outer Shield 71m. Its a flux core wire that you use with gas, and is designed for outdoor structural welding, with CO2 as the gas. Its really good shit for this type of work, and I believe...maybe..that your MIG would run on the genny when using this. Is your welder capable of running .035 or .045 wire? If so..then load it up with Dual Shield and make some test welds.
Gunner
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Reply to
Gunner Asch
No. The problem is not running it after you switch it on, the problem is the amount of surge current it draws WHEN YOU SWITCH IT ON.
I've never tripped the 50 amp circuit breaker while welding, even with the machine cranked up all the way to 225 Amps., after the machine is switched on. The circuit breaker trips, about once in ten times, at the moment I switch on the machine, using the ON/OFF switch on the machine. First, you hear a click from the switch on the machine, and a split second later, you hear a click from the 50 Amp circuit breaker at the service pannel, if you listen closely; otherwise, the two clicks are so close together, they sound like one.
Well, in theory you can. In practice, I use MIG for sheet metal and stick for structural steel. When it comes to structural steel where my own safety is involved, I tend to be an old fashioned guy who prefers stick so, I'll let others speak to this.
If you already know which end is up on a welder, I don't see why you don't rent or lease an engine driven welder for the project. I would.
Reply to
Speechless
I have a small 110 volt MIG that I use for thin stuff. Everything else is done with a Miller engine drive that has a 8KW generator capability as well. It will run CV, but stick electrodes are all that I have ever used. I use it for a generator more than for a welder. How about trading up to an engine drive? I wanted to avoid the expense of adding a welder circuit.
Reply to
Thomas Kendrick
I have a similar buzz box that I run in the garage from a 30A breaker (as I only have #10 wire to the garage). I can blow the breaker at full amperage but usually run at 110 or so and have no problems, including switch on. I don't know if a 5500 gen would run the welder at 150 as the gen would only be producing about 24A max but it's worth a try IMO and you could also work the welder at a lower amperage if possible.
Laurie Forbes
Reply to
Laurie Forbes

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