Miller 250 Dialarc -- current draw

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I've been looking at used transformer DC stick welders and came across a nice Dialarc 250, about 15 or 20 years old.  I was ready to jump on it and, just to be on the safe side, ran the amps specs by my electrician.  I wanted to be sure that there would be no issues with plugging into the "240V 50A" outlet (residential service in my garage) that I presently use for my Thunderbolt AC welder.  He looked at that maximum current figure of 68A and suggested that I think a bit more about this machine.  While he agrees with a lot of people on this and other boards that normal home shop use will probably present no problems if I watch the amps, he is not enthusiastic about the idea of having to monitor current to avoid an overload should I one day drift into a high-draw project.  He says he can up the breaker amperage, but this apparently would get me into industrial-installation territory, and I gather that I would not like the bill for the job.Could use some advice.  For 6013/7018 welding jobs I typically do such as normal shop repairs, fences & trellises, shop carts, etc., is it really OK to just plug into the 50A service outlet and go on welding?  I know I can do that, but is it OK to do that?And then there is the small matter of having a welder that weighs close to 400 pounds....  No, not ready to start looking at inverters.         -Marty-
Reply:If your service panel is in your garage, just run a heavier circuit for the Dialarc 250 and forget your worries. Running a 240v circuit isn't rocket science even at 70 amps. Do it yourself and you'll only be out the cost of the heavier wiring and a circuit breaker if the welder is hard wired in. You can probably get away with running the welder on your 50 amp circuit, but why buy a Dialarc 250 if you're never going to use the extra amps?Lincoln PrecisionTig 275Miller 251Miller DialArc 250Bridgeport millHossfeld bender & diesLogan shaperJet 14 X 40 latheSouth Bend 9" 'C'Hypertherm 900Ellis 3000 band saw21"Royersford ExcelsiorTwo shops, still too many tools.
Reply:I did what WyoRoy suggested on my Airco 300.Wired direct to a big breaker and when I'm done for the day I turn off the breaker as well. Same for my air compressor.Learn to wire, it saves you money and gives you the freedom to make changes and additions.Dave J.Dave J.Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~ Syncro 350Invertec v250-sThermal Arc 161 and 300MM210DialarcTried being normal once, didn't take....I think it was a Tuesday.
Reply:50 Amps would be useful and if he could bump to 60 or 70 it would be even better. If the outlet is for welder use only, it is sometimes possible to run a slightly larger breaker on a certain size wire due to the duty cycle."USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:I have an Idealarc 250 that I ran an outlet to with 8awg.  I used a 40A breaker because my box had an unused one and I'm cheap.  I've never had a need to go past 140A using 1/8" 7018 or 5/32" 6011 and have never had my breaker pop at that level.  And, for home use, I don't see needing to go any higher than that- multipass will handle any thick stuff that might find its way to your home.  I would say a 50A circuit would be fine.  WyoRoy asked why buy the welder if you won't use the extra amps- I'm assuming that the higher duty cycle is your reasoning (as well as DC capability).
Reply:Originally Posted by mattsandness...WyoRoy asked why buy the welder if you won't use the extra amps- I'm assuming that the higher duty cycle is your reasoning (as well as DC capability).
Reply:That machine needs at least a 70 amp line with proper-sized wire for that amperage. You would need a #4 size wire to carry 70 amps. It you have a space in your home breaker box, why not pull in a new, dedicated line to power your welder? That will be much safer since the wire isn't going to heat up. Your ground can be smaller than the two power lines and you don't need a neutral. I have a 100 amp sub panel in my barn shop. The welders are operated on the 70 amp line one at a time and I've yet to pop a breaker.Miller Millermatic 252Miller Syncrowave 200Liincoln AC-DC 225Victor O-A Set
Reply:I ran my Dialarc for a couple years off a 30Amp plug (dryer).  When you power it on, the in-rush (startup spike) will pop the breaker sometimes.  Sometimes it takes 2 or 3 tries to get it started (throw switch, pop breaker, reset switch, walk over - reset breaker, walk back, lather rise repeat).When I finally put a 50Amp in, it worked everytime.Note, I was told that by constantly tripping the 30 Amp breaker I would have weakened it.  I replaced the breaker and it made zero difference - still tripped as easily) - FYI, this was old school Square-D.Keep in mind that Miller's numbers are worse case.  AC, amps maxed and you are trying to break the arc.  I think max AC is something like 310 Amps...  Not sure what rod you would be welding with.All sounds good so far... until I sold the welder.  The guy who bought it initially said he was popping a 50 Amp breaker.  Then somehow everything started working.  No idea what he did.  Maybe had the wrong size breaker?This was a 1978 Dialarc HF.  To my knowledge it is still running perfectly today.Pricing should be no more that $500.  (I've seen recently some clowns asking $1200+ for HF and non HF units).I wouldn't fear the power aspect.  I'd fear the shear size...  400+lbs.  But at the right price I would live with the size.Con Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:Thanks for all the information, guys.  Very informative & helpful.  In my original post I said I wasn't going to look at inverters (a big reason being that I don't know enough electronics to know which way to jump should a board crap out or something similar happen).  And then, a couple of days ago, a friend lent me, on indefinite loan, an unused inverter that he had and said, try it out.  I did and I liked it.  I played around, using DC, with arc force and some of the other knobs.  They did things I never missed in the past but which I see could easily spoil me.  The machine is an Everlast Powertig 250EX.  So where I am now is that although I am still open to a transformer machine I am no longer actively searching for one.  Going to use the borrowed inverter for a spell and see where I am in a month or two.