Electrical question for a miller unit in my garage

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I have a chance to buy a Miller 300A/BT tig welder and I need to find out if I can use it in my garage. My house service is 200 amp and I would like to know if this unit is to big for my service. My garage to service box is 30 feet if that helps. Also, I plan on welding aluminum pipe 1/8 to 3/16 thick on an old crankup aluminum tower for my antenna. Any help would be appreciated. Thanks in advance, Sam near Detroit, MI
Reply:You need to find out what power your welder requires, if it needs three phase power than your out of luck.....There is no such thing as three phase in a residential atmosphere..... I don't know of a single power company that will supply three phase power to a residence.You home most likely has single phase 230v.You need to find out first what the welder requires and then what service you have in your garage. You might only have 110v in the garage. Washman
Reply:Originally Posted by WashmanYou need to find out what power your welder requires, if it needs three phase power than your out of luck.....There is no such thing as three phase in a residential atmosphere..... I don't know of a single power company that will supply three phase power to a residence.You home most likely has single phase 230v.You need to find out first what the welder requires and then what service you have in your garage. You might only have 110v in the garage. Washman
Reply:What does the electrical plate specify as the voltage and amps?There are no small projects
Reply:Originally Posted by imagineerWhat does the electrical plate specify as the voltage and amps?
Reply:The only one who can answer this question is you or an electrician that you pay to come over and perform a "load calculation."  If we can assume that you will NOT run other large loads at the same time, then of course you can run your welder.  Keep in mind that the machine's input will change based on output, so it will only draw its maximum when you're welding at maximum.Since I doubt you will be moving this unit around, I'd recommend a disconnect instead of a receptacle.Here's a sample load calculation worksheet.  It can be confusing, but maybe you'll get the idea.Also, I don't see a 300A/BT on Miller's list for owner's manuals.  Is that the correct model number? Attached ImagesLas Vegas SFD_Residential_Electrical_Load_Calculation_Option.pdf (109.2 KB, 49 views)
Reply:Originally Posted by MAC702The only one who can answer this question is you or an electrician that you pay to come over and perform a "load calculation."  If we can assume that you will NOT run other large loads at the same time, then of course you can run your welder.  Keep in mind that the machine's input will change based on output, so it will only draw its maximum when you're welding at maximum.Since I doubt you will be moving this unit around, I'd recommend a disconnect instead of a receptacle.Here's a sample load calculation worksheet.  It can be confusing, but maybe you'll get the idea.Also, I don't see a 300A/BT on Miller's list for owner's manuals.  Is that the correct model number?
Reply:That's funny!  I was about to say that the other one wasn't a choice either and when I hit "quote" your editted version appeared with the correct model number.  I thought I was losing it at first.Keep in mind that the 96A input is at RATED output of only 300A.  The machine can output much more when needed, which is why a fuse of 175A is recommended at the 230V input you can provide it.This means that to power this unit to its full potential, you likely don't have the ability to provide a circuit that large from your panel.  You would need a 400A panel with at least two 200 breakers, one to feed a fused disconnect to the machine.But, like I said, you can always give it power and see how high you can go before tripping a 125A breaker, which is probably the largest you can put into your existing panel.  What is your existing panel?
Reply:Originally Posted by WashmanThere is no such thing as three phase in a residential atmosphere..... I don't know of a single power company that will supply three phase power to a residence.
Reply:Originally Posted by MAC702That's funny!  I was about to say that the other one wasn't a choice either and when I hit "quote" your editted version appeared with the correct model number.  I thought I was losing it at first.Keep in mind that the 96A input is at RATED output of only 300A.  The machine can output much more when needed, which is why a fuse of 175A is recommended at the 230V input you can provide it.This means that to power this unit to its full potential, you likely don't have the ability to provide a circuit that large from your panel.  You would need a 400A panel with at least two 200 breakers, one to feed a fused disconnect to the machine.But, like I said, you can always give it power and see how high you can go before tripping a 125A breaker, which is probably the largest you can put into your existing panel.  What is your existing panel?
Reply:Originally Posted by aa8wlThe box has (2)  100 amp breakers at the top so I believe it is a 200 amp service.
Reply:Originally Posted by MAC702That changes everything.  You have a 100A service.  The two breakers are tied together, right?  In this configuration, you add the voltage, not the amperage, so you have 240V 100A service, each breaker taking one half of the 240V, which is how you mostly have 120V loads in a residence.
Reply:You still have 100A service, even if your main breakers aren't tied together, which I've not seen before, but there are older installations across the country with which I'm not too familiar.Each leg is 120V of 100A.  Taken together you have 240V, but still 100A.
Reply:Originally Posted by MAC702You still have 100A service, even if your main breakers aren't tied together, which I've not seen before, but there are older installations across the country with which I'm not too familiar.Each leg is 120V of 100A.  Taken together you have 240V, but still 100A.
Reply:So, now we're wanting to power a machine that can draw over 100A alone, from a service of only 100A.  Seems like you need to upgrade your service or get a welder which draws a lot less power.  You could put the welder on a 50A breaker (even up to a 100A) likely and fit it in the panel, you just won't get far or with much before you trip it or the main.
Reply:I don't know what you plan on tigging or your budget.  You might want to take a look at these 2 inverters.Thermal Arc TA-185 tsw which can be had new with a large bottle for about 2 grand.  The next step down is the Ryland if your budget is tight.  Several guys over on the Hobart board have the TA's and everyone's happy with them.I haven't heard of any problems with the Ryland but there's very little being said about them good or bad.  Don't waist you money on the HF junque.Just my 2 cents worth.  Godd luckDennisThermal Arc 185-TSWMillermatic Challenger 172VictorO/AAtlas Craftsman 12 by 24 LatheEsab PCM-875Wholesalem Tool Mill-Drill
Reply:huh....Well, I bought a Dialarc 300 HF about 10 yrs ago for a grand; and it came with a pickup load of metal stock and a bunch of other tools and junk he needed out of his garage right away, to meet his closing-date... :lol:Anyway, it is one of the smoothest welders I've owned; and I've owned half a dozen so far.  I love that machine.  I've never had to touch a thing; let alone the HF/tungstens.  Rock solid machine....400 lbs worth.I ran burial-rated 200A cable underground from the 200A entrance outside the house, 75' to the shop; and installed a 200A Square-D breaker panel (the original heavy-duty square-D, not the 'homeline' stuff).I ran the Dialarc 300HF on a 100 amp breaker and never tripped it; even when cranked full while doing 3/4" plate repairing my backhoe.I don't know if the "330" needs more juice than my 300; but if so, I believe that a 125a breaker -is- made for the square-D panels.  Just make sure you're not running any other heavy loads while you weld.  No electric-stove, electric-dryer, etc..  Normal lights and fridge won't make much difference.By the way, 3-phase is available in homes in lots of places; but they charge up the ying-yang to put it in.And besides that, you can build a rotary phase-converter from any old working 3-phase motor and a hundred bucks worth of oil-filled 'run' capacitors.  I got my motor at the industrial boneyard for $5/HP...it's a 7.5hp...and I power a 13x40 lathe and a mill from it...no problemo.For a 100 amp load like a 3-phase 400 amp welder, you would want to study the subject and do a good job of design and construction, of course...Where there's a will, there's a way!  :lol:
Reply:Hey dozer, when you ran your 300HF on 3/4 plate was that stick? Did you try alum. I have a 350HF paid $500.00 (needed a bottle).
Reply:you have plenty of power  i have 200 in the house and it feeds my garage with 80 amp and you never run the miller wide open ...........pete
Reply:How about this one? I want to put a Millermatic 210 in my garage, I already have a 30A outlet in the wall that I plug my generator into for power outages(it goes to a GenTran 10 circuit box), can a box or switch be configured at the panel (200A service) so I can add a 30 amp breaker and have this outlet in the garage hot??? Thank you in advance for your reply
Reply:I bought a miller 330 a/bp over 30 years ago.  Very nice machine.  When on the high range my machine pulls 105 amps at 240 volts single phase.  I used a 100 amp breaker and it never tripped while welding on the high range.  This thing will put out over 450 amps on the high range.  For welding the stuff you want to weld, the mid range should work just fine.  That would be about 250 amp output.  Since I moved to Pennsylvania I only use it on the mid range and use a 60 amp breaker.
Reply:Scootermsp, you should really start a new thread for a totally new application like this.Without seeing this generator tie-in that you have, I'd just recommend a new dedicated NEMA 6-50R receptacle to a new 30A or 40A breaker (even 50A if you want to make it available to bigger welders in the future.)It'll be even easier if the panel is in the garage or has its back against the garage, as many do.