Newbie question- Single versus three-phase.

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Hey yall, gotta quick question for ya.I've got a '97 Miller Legend NT CC gen-welder. I've done some homework on the possibility of running a voltage sensing feeder, but the consensus seems to be that it's an inferior weld and very difficult to use on thinner stuff on account of only working in spray mode.So I'm thinking the smart and cost effective thing to do is to get an old 220V millermatic and just plug it into my auxiliary generator. They're cheaper than voltage sensing feeders and it's said they lay a much better weld. This will have the added benefit of leaving my stick setup hooked up and ready to go for when I want to weld through paint, manure and 20 years of rust. (yyyup, I'm a farmer)My only concern is the phase setup of that Millermatic. Having taught myself the little I know about welding, I've got some knowledge gaps in key places.The auxiliary generator on my Legend puts out single phase AC power. What does this mean for the welder I want to plug into it? Can I snag any old Millermatic off of Craigslist and plug it straight in? Plug it in with some sort of intermediary converter? Not plug it in at all?Thanks for helping a newbie out.Cheers,Craig
Reply:Figure out how many amps your generator is putting to the plug in - and get a welder that draws a little less input amps -
Reply:I think you are asking if you can run 3ph equipment off of your single phase generator. The simple answer is "no".  (Well you might in some cases but the power would be tremendously reduced like 80 or 90%?)    That's probably why you see the old 3ph equipment cheap:  It's for industrial use only.There are single phase to 3 phase "converters" (usually a big motor driving a 3 phase generator) but there is power loss through that process.Ken
Reply:Jesus,Has the OP done ANY homework?A 5 minute search would reveal that NEARLY ALL the smaller Millermatic Mig welders (especially those that could possibly run on his generator/welder) are 1 Phase.The only real question here is does his welder/generator have the output to run them (amp output).  I'm not going to do that research.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Jesus,Has the OP done ANY homework?
Reply:The official welder for the application seems to be the Millermatic 180. Keeps me in the range of my 5000 watts of aux power and gives me the most possible output. And they're 800 bones new. Can't beat that. Thanks again for the shove in the right direction.
Reply:I am not 100% certain on this-I am sure someone else here would know better-but you might have to switch the millermatic from/to 230/460/575 input voltage. On one of my other machines I've had to do this to operate on 230 volt input. You will have to open up the machine & wire it according to the diagram on the inside. Again... I am not an expert in this! It worked the few times I did it though. Another thing to keep in mind is the amp draw. Your amps will spike when you will turn on the millermatic so make sure you stay within/below the rating on the generator. That should be obvious but...just in case. Hope you find something that works for you!
Reply:Both LN-25 and 12 VS feeders have cv - cc switches in them my friends use them all the time with  both cv &cc power supplies and the wire still melts off . rent one and try it for a day . A 220 v single phase mig and a gen set works too.
Reply:Yeah to confuse the situation this welder's been around the block. And obviously rewired a few times. The 230V is not in the stock location, and I haven't quite been able to trace the wiring so far (been working on other things like the starter, battery setup, output terminals etc). The direct response I got from Miller was that I could run a 140, a 180 or a Passport without outrunning my 5000W auxiliary generator. Renting one is a fantastic idea. If it works, I'll know right where next year's tax return is going ;-)
Reply:No, no. I've solved that problem. All the little millermatics are single phase. This was what Sundown pointed out to me. (And I apologize for the grumpy response) My real problem here is (and it's been covered in a few other threads) trying to Mig off my CC genwelder. Between this forum and Miller's surprisingly good customer service I've determined that it's possible if I use a nice modern, efficient Millermatic. And from my scattered research, mostly in other threads on this forum, I've determined that this is probably preferable to running a voltage sensitive feeder that can only work in spray mode. Seems like, awkward as it sounds, the cheapest way for somebody without 220V power access to get really Mig welding is a CC power plant and a 220V Mig plugged into it. For someone with limited knowledge and therefore limited ability to work the market, I worked this out to be cheaper than buying a CV power plant and a nice wire feeder. And I think the Millermatic 180 should would just fine off my little 5000W generator. Even Miller says so!
Reply:thought I saw the statment of 50 amps, a 5000 watt welder does not put out 50 amps  (it may if your running two 25 amp loads on 120, (and it should be closer to 20 amps), but  on 240 you have about 20 amps, per leg of the 240,  or about 20 amps on each side at 120 volts,(but unless it has some special switch to combine the two sides of the alternator there is not a way to get 40/50 amps at 120volts)
Reply:Hmmm, so it is. Manual says I've got 20 amps available at the 240v if I'm not running anything off the 120s. And the input power of a MM180 is listed at 21.7 amps. And as SilverSmith mentioned, there will of course be an amperage spike turning on the machine. With these numbers, it looks like that spike will fall outside of my generator's rating. Sounds like this has the potential to be a great way to get rid of fuses. Which makes me wonder about the information I got from Miller customer support- "Also you need to remember that your Legend NT only has 5000 watt of aux power. Which would limit you to Millermatic 140, 180 or Passport." Hmmmmm
Reply:MIG welders do not draw much of a spike when they start up, and I would think that Miller customer support knows what they're talking about, especially when it comes to their welders.Keeping in mind the 5000 watt limitation on generator power, there are several options that will give you more top-end power than the MM180. Miller's new Multimatic 200, the Thermal Arc 181i, and the ESAB Caddy MIG 200 come to mind. They are inverter-based units, which will give you more output power for a given input than a transformer type machine like the MM180.You might also consider the MM211- it may draw a bit more power than the generator can handle at it's maximum setting, but will not give you problems at lower settings. It will also give you the versatility of running off of 120 or 240V when you have line power available.JohnA few weldersA lot of hammersA whole lot of C-clamps