Miller Dialarc HF TIG running on 30 amps?

admin

This probly sounds rediculus, but does anyone know how far I will get trying to run an old (possibly early 80's) Miller Dialarc HF (I think it's a 250) on 230 volts single-phase with a 30 amp breaker if I'm using the machine in AC with high frequency?   How about in DC, does that use less power?  The tag says the machine has 100% duty cycle at full output power, using 100 amps on 230v single-phase.I've run my rectifier MIG welder at full power (200 amps) without popping the 30 amp breaker, but that's a DC constant-voltage machine, so I don't know how that compares to a constant-current machine for power consumption.The reason I'm asking is I might be able to get this machine very cheap and even though it's old, heavy, big as a whale and lacks the fancy electronics of today's machines, it has most everything I'm looking for in a TIG machine that can weld aluminum and is known to be in good working condition.   It has AC, squarewave, DC+/-, AC balance and HF (start and continuous), and I think I remember there being an inductance control and hot-start for stick.  It has a foot pedal, water cooler, TIG torch, stick leads, running gear w/ bottle rack and the argon regulator too.   The machine is at my job and has been sitting unused for a long time and was seldom used before the only person who knew how to TIG quit a couple years ago.   It was primarily used as a stick welder for occasional repairs to broken machines in the plant and once in a long while my old supervisor would TIG with it.  It hasn't been used much in the last 20 years and from what I hear, was only used for production for a short time when it was first new, untill they switched processes to MIG cause TIG was too slow.  I have seen some pretty nice TIG welds on aluminum done with this machine and I've used it for stick welding too so I know it works and think it would be a good machine, IF I can run it on my limited electricity.So, do you guys think this machine will weld anything with only 30 amps going in??Last edited by DesertRider33; 11-17-2006 at 03:50 AM.
Reply:DC will likely use more power due to the losses in the rectifier.If you're using a 30 amp circuit, and the welder is rated at 100 amps, you will probably get about 30% of its rated output before it pops the breaker.Though, I find it interesting that the 200 amp mig did not pop the breaker.  Did you ever run it wide open (highest voltage, max wire feed speed?) for at least 5 to 10 seconds??
Reply:So I might get 80 or so amps out of it?   Is that enough to AC TIG 1/8" aluminum?  I've run the mig at max voltage and very high on the wire speed for long enough to melt part of the torch running several beads in succession but didn't pop the breaker and the machine didn't shut down for thermal protection.   The specs for the mig machine say it pulls max 30 amps at max 200 amps output, 20% duty cycle.  I forget what the max voltage is supposed to be.   It doesn't have meters on it.  It's an  HTP MIG200.
Reply:I did a search for dialarc hf and found some on ebay.   I cant believe some of the prices for these old machines.   The one we have at work has the two slide controls next to eachother on the left side and the rheostat knob is at the top in the center, with the balance control knob on the lower right, switches along the bottom and the face is black.   From reading more about them, I guess it is a sine-wave not a square-wave like I thought, but it does have the cleaning/penetration control  and start/continuous HF.   Unless this one is different from the others I saw pics of, I was probly confused about the inductance and hot-start controls.   Doesn't look like the others have those features.   I'll have to take a closer look at next week.I'm kinda confused about the water cooler.  All the machines like this seem to have it.  I thought the cooler was just for the torch, I've never really looked to see where the hoses ran to before.  From what I was seeing in the pics of these other machines though, it appears the machine itself uses the water for cooling too?  Sounds kinda scary that there might be running water cooling high voltage electrical parts inside the machine...
Reply:The dialarcs are pretty bullet-proof machines and good all around welders.  The HFreq ones I have seen do not have a cooler intergrated into the welder but use an external one that connects to it.  I would think you would be pushing it to get the machine to tig 1/8th aluminum on a 30 amp breaker, but it might.  Getting the puddle started will be the problem.  If you can get the metal wet, you can probably accomplish the weld.  But, my guess is that this is the point you will get the trips on the breaker...right when you are pressing down on the pedal to start the puddle.  I have the non-hf machine with an add-on hf box.  It ran on a 50 amp breaker for years without much of a problem, but I rarely ran over about 200 amps in ac.  When I did, I wired it directly into the panel (not a suggestion, just telling you what I did).  I had a couple of trips on the 50 amp, but nothing to complain about given the manual suggests something like an 80 or 90 amp breaker.Smithboy...if it ain't broke, you ain't tryin'.
Reply:"The HFreq ones I have seen do not have a cooler intergrated into the welder but use an external one that connects to it."   -That's exactly right, the one at work and the ones I'm seeing on the internet use a seperate water cooling unit that sits on top of the machine but connects to inlets and outlets on the machine.   I was just surprised to see it connected to the machine instead of the torch...."I would think you would be pushing it to get the machine to tig 1/8th aluminum on a 30 amp breaker, but it might."   -Yeah I kinda thought I was doing a bit of dreaming there...  How thick of steel do you think it will TIG using DC on 30 amps?"It ran on a 50 amp breaker for years without much of a problem, but I rarely ran over about 200 amps in ac."   -If only I could come up with 50 or 60 amps I think my machine choices would be much wider.  Being able to hit 200 amps in AC I think would enable me to weld everything I can reasonably expect to do at home.  I just dont know enough about electrical to identify if that is possible here or not.  When I had the extra 230v plug wired from the breaker box to the other side of the garage where the welders and compressor are so I wouldn't have to run the extension cord accross the garage every time I wanted to use the machines, he said he couldn't do it as an extra plug in addition to the dryer plug I was using on the opposite side of the garage that was already there.   He said there was no place for an additional 30 amp breaker and no way I could use both plugs at once so he disconnected the original wiring to the old dryer plug, since our dryer is gas anyways, and used that breaker for the new plug.  Basicly I take that to mean there's no way to get 60 amps of 230v going all at once in our garage, be it 30 amps to each of 2 seperate plugs or 60 amps to one.  There is another 230v breaker, I forget how many amps, going to the electric range/oven, but we need to use the oven...  I like to eat!  I'm going to have to ask the neighbors how they got power to their retro-fitted A/C units.  None of these houses came with air conditioning and I'm curious now where they got the power from to run them.   Either they all gave up their electric dryer outlets (or the oven) to run their air conditioners, or their electricians know something mine doesn't.  I know the one neighbor was running a 230v compressor and his A/C at the same time before cause I could hear them both going at once and I know that compressor was on 230 cause we bought it from him before he moved out and have been using it, on 230.   I dont ~think~ the A/C units are running on 115v...  Is that even possible?Last edited by DesertRider33; 11-17-2006 at 09:54 PM.