Will phases affect A/C welding

[swamper8]

hello all. I have a old Hobart Cybertig welder. (1976) I am running it in its 220V mode (it's a single phase machine) The 110V panel where I am is boogered up (both busses are fed off the same meter terminal) so I was forced to grab 120V off two legs of a 3 phase panel. So basically I am running my welder on 208V from a 3 phase box. I know that in a standard residential 110V panel, the voltage is coming in at 60HZ but the phases are 180 degrees out from one another. In the three phase box, I should still be getting 60HZ, but each phase (3 of them) are 120 degrees out from one another.
I would appreciate everyone's thoughts on if this would affect the functionality of the welder in any way. I.E. the cleaning of a AC aluminum weld etc.
Thanks!

[bvweld]

Your phase relationship as you described will not effect your cleaning action of your AC output. Your good to go

[swamper8]

Well that's good to know. can you think of any reason why I have an unstable arc? I am using 1/8" pure tungsten, with a small ball on the end. The machine is in AC mode, with continuous arc selected. I am trying to weld 1/8" 6061 aluminum square tubing. The arc seems to "sputter" or "spit". Also, I can't keep the weld from being contaminated unless I turn my argon flow up to 35CFH. If I set it to 15-20 like I want I get little black specs flowing off my filler rod and into my weld puddle. I have been thoroughly cleaning the surface with a dedicated SS wire brush and acetone before trying to weld.

[griff01]

hello all. I have a old Hobart Cybertig welder. (1976) I am running it in its 220V mode (it's a single phase machine) The 110V panel where I am is boogered up (both busses are fed off the same meter terminal) so I was forced to grab 120V off two legs of a 3 phase panel. So basically I am running my welder on 208V from a 3 phase box. I know that in a standard residential 110V panel, the voltage is coming in at 60HZ but the phases are 180 degrees out from one another. In the three phase box, I should still be getting 60HZ, but each phase (3 of them) are 120 degrees out from one another.
I would appreciate everyone's thoughts on if this would affect the functionality of the welder in any way. I.E. the cleaning of a AC aluminum weld etc.
Thanks!

Using two phases from a 3 phase service is the same as "two legs from single phase" service. Be sure to check the actual voltage across the two legs you use with a volt-meter.

Most newer machines can handle 10 to 15% variation in supply voltage. The older machines probably can or they would be smoking all over the country!

The 230v single phase service at my shop actually runs as high as 256V phase to phase.

Griff

[swamper8]

Thanks. I am beginning to think my problems are with my welder. I have 210V between phases out of my three phase panel. Welder is setup for '230' volts. So my math tells me I'm at 8.7% less than ideal. So I guess my power isn't the problem. I think my welder needs a 'tune up' so i am going to post at the Hobart forums.

[shorerider16]

Using two phases from a 3 phase service is the same as "two legs from single phase" service. Be sure to check the actual voltage across the two legs you use with a volt-meter.

Most newer machines can handle 10 to 15% variation in supply voltage. The older machines probably can or they would be smoking all over the country!

The 230v single phase service at my shop actually runs as high as 256V phase to phase.

Griff

Small variations won't harm the older machines any more than the newer ones, the only difference is the odler one's output fluctauates with the input.

[Bodybagger]

Your input voltage is set wrong

When you use a welder on 120/240 single phase set the input to 230v setting.

When you use a welder on 120/208 3 phase, set the input voltage to 200V

The relationship between individual phases on a 3 phase system is as follows: phase to phase voltage equals the phase to ground voltage of one leg TIMES the square root of 3.

In older days, outlets were usually 110-115V. 115*1.732=199.1 (roughly 200v). This is why the nomenclature of 220v and 230v stuck around. This welder wants 208 volts or 240 volts, but it's LABELED 200v or 230v.

Today, it is not unusal for outlets to run at 120-125 volts. This bumps up the voltage you see across three phases proportionally. However, it doesn't change the fact that your welder is not properly configured for 120/208. Transformer type constant current welders don't like low voltage. Place your jumpers in the 200V position and your arc will stabilize. Just remember to replace them to the 230v position before connecting it to a 240 volt outlet.

[swamper8]

Well, according to the manual I have for the welder, if I reference the correct electrical diagram it says I only have 230/460/575 settings. My model is 5283D-1. I did find a electrical diagram in the manual that has 208/230/460 settings but the diagram number does not corespond to my model number in the setup table. Even on the ID plate on the welder it only says 230/460/575. Soooooooo I guess I'm stuck with the welder set at 230 but have only 210 applied. (I measured across the phases with my DVM) Does this mean I won't ever be able to get my AC arc to settle down? I found that the spark gap(s) were at 0 (contacts were touching) I removed the contacts, cleaned up the surface(s) and re-installed with a .008 gap. I found that I had to change some of my settings around from what I normally have but it didn't improve the stability of the arc or the contamination problem I'm having with my aluminum welds.

[DSW]

Is this a temporary job or will this be your perm. work space. If it's perm./long term you may be able to get a wall mounter transformer to correct the voltage. We frequently need to install these on high voltage X-ray equipment that I help to install part time. They often want 230v and we have 208v. I just do most of the bolt up work and my boss is on vacation so I can't verify if this will work for you or not.

[swamper8]

This is semi-permanent. I am using a corner of some industrial rental space that a friend of mine uses for his business. Unless he goes out of business I can use the space for as long as I want. I once tried to find what I was told is a 'buck boost' transformer. However I think one that is capable of supplying 40 - 50amps is very expensive. Though I don't know this for sure.

[DSW]

I'll try and ask my boss when he gets back where he gets the transformers we use and how much. It could be 1-2 weeks before he gets back from Hawii. I'll PM you my Email address, shoot me one in a week or so to remind me to ask him.