Use a 3 phase welder on single phase?

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About 15 years ago, I moved to a neighborhood that does not have 3 phase. When I moved here, I put my Dad's Hobart RC250 with 2000 wire feed (220 3 phase) in the basement (storage) which is where its remained to this day. When we retired it, it had hardly ever been used, so when we recently pulled it out and cleaned it up, it still looked as if new.  Now, what brought this recent activity about is that I ran into a professional welder (a casual meeting, so I cannot attest to his experience, skill or knowledge) who told me that he was pretty sure "those old 250's can pretty easily be rigged to run on single phase."Is this true? If so, could somebody share some insite on the process?  Would this be a reasonable welder for general purpose welding by today's standards?  Thanks to anyone who can shed some light on this. Jim ([email protected]).
Reply:Generally, a 3-phase-only machine is just that, 3-phase-only.   Some machines can run both, but I'm guessing that old Hobart isn't one of them.   I think you're out of luck.   There are phase converters for running 3-phase motors on single phase, but they're not for welding machines.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:What Desertrider said.Look at the faceplate for electrical requirement. It will say exactly what is needed.Granthttp://jackalopefab.com/MM210Synchrowave 200DXMiller XMT350 w/60series feederMiller Bobcat 250 with SGA 100 and spoolgunHTP PlasmaFull Machine shop with everything
Reply:Jim,I also have a 3-phase RC250 that I purchased a while ago with the intent of running off single phase from a rotary phase converter.  That is probably your best bet if you want the full capacity of your welder on single phase.  You might be able to re-wire the RC-250 to run on single phase, but you'll lose some capacity for sure.  The ability to re-wire it will depend on how the power transformers are wired if I remember correctly.  This guy has a write up on the conversion of a similar Miller welder:  http://shdesigns.org/Welding/CP-250/cp-250mods.shtmlI purchased the original owners manual from Miller (owns Hobart) for the RC-250 if you want a copy.  It has the wiring schematic in it, although the copy is a bit hard to read in some spots.  That's about the best I can do right now as I haven't had much time to mess with the welder.Linde/Union Carbide HDA-300Hobart RC-250Lincoln AC-225Lincoln WeldPak 100 Hobart Stickmate LX Victor OxyAcetylene
Reply:NYS3,Thanks for the info! The conversion demonstrated in your referenced webpage makes perfect sense to me and confirms my original suspicions. Also, I'd LOVE a copy of the manual! Please email me at [email protected] at your convenience and we can make arrangements.Jim
Reply:Originally Posted by DesertRider33Generally, a 3-phase-only machine is just that, 3-phase-only.   Some machines can run both, but I'm guessing that old Hobart isn't one of them.   I think you're out of luck.   There are phase converters for running 3-phase motors on single phase, but they're not for welding machines.
Reply:Hmm, that's the first I've heard of using a phase converter for a welding machine.  They are commonly used for lathes and mills and other electric motor equipment.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:"It all depends on if you just want to melt metal or if you want to weld. If you want to melt, then use a converter, if you want to weld, get 3 phase or get a new welder that runs off your power" Direct quote I was told when I asked about this when I moved into my old place. It was explained to me that with the high starts and power spikes on welders the converters are not good to power them. Unless you don't care to know your true amps, and don't need uniformity. For myself, I just went out and bought a 3 phase genset, worked great and now I have great backup for power outages.
Reply:Originally Posted by h2oboy"It all depends on if you just want to melt metal or if you want to weld. If you want to melt, then use a converter, if you want to weld, get 3 phase or get a new welder that runs off your power" Direct quote I was told when I asked about this when I moved into my old place. It was explained to me that with the high starts and power spikes on welders the converters are not good to power them. Unless you don't care to know your true amps, and don't need uniformity. For myself, I just went out and bought a 3 phase genset, worked great and now I have great backup for power outages.
Reply:Originally Posted by lars66I will assure you that this machine has been the dailey driver in a general welding repair shop that puts out work quality to match anyones.
Reply:Originally Posted by DesertRider33Hmm, that's the first I've heard of using a phase converter for a welding machine.  They are commonly used for lathes and mills and other electric motor equipment.
Reply:Originally Posted by tresiIt can be done with a rotary converter. It won't work with a static phase converter or what some call a phase shifter.
Reply:Originally Posted by DesertRider33That must be the confusion, I didn't know there were different types of these things.
Reply:I've got enough junk around  I just put together what I need at the time and pull it down later to build something else.You are right though, if you don't have the parts, and it takes too long to do ,it's not worth doing.
Reply:Lots of military parts and industrial, makes you feel funny to hook a $500 computerized digital battery charger to a $400 car.
Reply:practicalmachinist dot com has an -entire- forum dedicated JUST to designing and building rotary converters; it's a -very- active forum, and well illustrated (guys work) too...