adding plasmacutter capability to TIG machine?

G'day,
It's only recently I learned about the possibilities of plasma cutters.
Since I already own a TIG machine (Esab AristoTIG DTD 250 ac/dc) I am
wondering: do there exist plasma cutting heads that can be used as an add-on for this kind of welding machines?
It seems that there's much overlap between a plasma cutting machine and a welding machine (esp. the ones using Argon as shielding gas). If I understand correctly, the max. current of plasma machines is usually quite small (say, 40-80A), quite within the reach of practically every TIG machine.
The fact that I haven't seen such add-ons makes me think there's something else I'm missing, why it can't be done.
Peter, The Netherlands.
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peter snipped-for-privacy@hotmail.com wrote:

Miller used to make such an add on unit. I asked the folks at my welding supply place about it and they said it sucked.
Plasma cutters do run fairly low current, but they do it at a much higher voltage than a welder. With all the recent compact and inexpensive inverter type power supplies, there isn't much to be gained by trying to do a plasma cutter add on.
Pete C.
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Too bad, but it almost sounded too good to be true.
But even the OC voltage of inverters (in my case, 92-100V) is not enough for plasma cutters? The OC voltage of transformer-based welding machines is much lower than that of inverters (about 42V, in my case for an old SMAW werlding machine)
Apparently the arc used in plasma cutters must be quite different from one used in welding (higher voltage & less current) ?
Peter, The Netherlands.
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The OCV of a Lincold Electric I was looking at was stated as 500V.

100VDC or more ( I would say 100VDC for small 120V units and 150 for larger 240V units)
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yugami wrote:

is the plasma output under load though?
CC welders have their voltage drop a lot while welding and a plasma power supply is not required to be either CC or cv
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Please keep in mind that I am not any sort of expert in terms of electronics or welder/plasma cutter design.

done quite a bit of reading but still don't understand the why's of everything) plasma leans more towards CC but it seems that designs that limit ripple on voltage to about 5% are much more succesful in keeping the plasma running.
I think the ouptut I stated is under load.
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