Thermal Arc TIG sets, 3 phase to single

By John H. Date 08-24-2002 17:18

Hello,
I am mainly welding as a hobbyist but at the moment I have a summer job making expensive gates for people with too much money. I managed to pick up this really nice welding set, a Thermal Arc 400s. The set is a DC Stick / Lift TIG deal with a maximum output of 400 amps in a box the same size as my current piece-o'-junk MIG welder! It's an inverter with digital arc control. Actually, I'm kicking myself for just missing out on an AC set as well. I should mention I bought it in an auction, hence all these questions a manual might help with (Anyone got one?).

I have a few questions to ask about this set though. First of all, do any of you know what type of termination the remote control has? Can I plug other brands into it? Secondly, have any of you ever looked into having a Thermal Arc set converted for it's phase and input voltage?

The set is designed to run on three phase, although I have this at work I'd like it to run at home as well. Thermal Arc sell a single phase version of this set and I'm wondering if the circuit is designed to have the same arc handling components on the boards and just different input power components. I mean, is it likely that I will be able to replace the three phase components or will they be rooted through-out the entire welder? My thinking was just that commercially, it'd be more economical for Thermal Arc to make them this way. The single phase set they do is 280 amps, so it seems as if they are using the same parts somewhere between the two and loosing the amps on the single phase set due to the nature of the supply current, not it's design.

Thanks for any help on this guys, I'll really appreciate it!
John H.

P.S. I took this into work and loaded it with a Murex Vodex 3.2mm rod (Which can take ten to twenty strikes on our set to start). I touched the job and the rod struck up immediately. I then used a 316 stainless 4.2 rod on some scrap and ran a thick, full penetration, clean weld in seconds with the welding set crying at my under use of it's immense output. Please bear in mind, I started stick welding just a few weeks ago! These are _beautiful_ welders if you're looking at one!

By stickguy Date 08-24-2002 19:46

you might want to check into a phase converter. I don't know how they would work with an inverter though.

By John H. Date 08-24-2002 20:41

The welder does actually run fine on an inverter, although I don't really understand the nature of how three phase and the pulses from an inverter work the set totally. I've had a think about that idea before but the problem with it is the set runs a mongo 21kva at full power, that burnt out our light industrial fuse box in seconds. I know a 1.5kw inverter can be pricey, nevermind one to take that much. I was thinking about rotary phase converters next but I believe that idea only works when it's connected to another three phase motor, not a welding set. So I'm narrowing it down to getting my electric supply company to put some idiot on the phone to tell me "Three phase is free!" on tape or changing the input side of the welder itself.

Any over thoughts?
Best wishes,
John

By billvanderhoof (****)

Date 08-25-2002 04:42

www.thermadyne.com
click- literature library
click- thermal arc
click- pro plus (R) 400s
click- operator service instruction manuals
You should now be looking at a page where you can order the manual.

Bill

By John H. Date 08-25-2002 12:49

Thanks Bill, I've ordered the manual. I hope it has a little more detail in it than their online catalogs! :)

John