If you're talking about a transformer welder it WON'T work.
A 3Ø rectifier is completely different from a single Ø rectifier.
Cost of a VFD to power a transformer machine would be killer as well.

On a motor driven machine you can buy one hell of a lot of welder for what the VFD will cost you.

 

You'd never get enough current on single phase power to run a 3 phase welder, even IF the VFD was 100% efficient and they aren't. Also a large VFD what be horribly expensive. It would be cheaper to just buy a new single phase welder.

FWIW there are a few 3 phase welders that will run off of single phase power but usually they just disconnect two of the three transformers inside of the welder which means that the welder can only deliver 1/3 of the power that it's rated for. So yes, it will work but it probably won't have enough power to be practical.

 

FWIW there are a few 3 phase welders that will run off of single phase power but usually they just disconnect two of the three transformers inside of the welder which means that the welder can only deliver 1/3 of the power that it's rated for. So yes, it will work but it probably won't have enough power to be practical.

Properly designed 1/3 phase machines are more efficient on 3 phase. The output is often identical or close but usually not going to cut it back to 33% capacity.

 

Thanks for the feedback - The metal plate indicates 230/460 amps so I need to pull the cover and see if there is a way to switch it easily or another adjustment with the transformers and adding capacitors.

 

Maybe if you post the model no. of your welder someone could help with converting it.

 

There are several threads on the net describing conversion of three phase welders to single phase. IIRC most of them are for Miller/Hobart, Good luck!

 

Google "Haas Kamp conversion" and then read to your heart's content. Just asking out of curiosity but what've you got? Maybe an old RC-301?

 

Any member of that cult posted a scope trace of the arc wave form from that mutilated contraption?

 

I would look at phase converter
They are simple build, low in cost and give ture three phase

VDF is like any other electronic it has short life spand
It for changing the speed motors

Dave

 

Model - Hobart RC -200
Amps - 200
Max OCV 35
% Duty cycle 100
Volts. 230/460
Phase 3 HZ. 60

Spec. 6430-1

 

You can check this out. I don't know if this fellow ever got his working but it should get you started.https://www.practicalmachinist.com/vb/transformers-phase-converters-and-vfd/hobart-rc-200-haas-kamp-295116/?highlight=hobart+rc-200
Or this one:https://www.practicalmachinist.com/vb/transformers-phase-converters-and-vfd/haas-kamp-3-phase-single-hobart-rc-200-a-301715/
Good luck.

 

Thanks all for the input.

 

I ended up building a 3 phase converter to power my 3 phase Hobart RC -200 mig welder with a Hobart 19 wire feeder.

15 hp motor, start capacitor, 8 run capacitors.

Sounds like bacon frying. I still need practice working on the argon flow, wire speed and current.

Any comments on fine tuning are much appreciated.

 

I assume you got this cheap because it is 3 phase.
Now there is a whole world of under-priced tools available as a side benefit of the RPC.
Hit Craiglist for that 7.5hp 3 phase table saw, plasma cutter, Bridgeport, monster compressor for sandblasting, mega grinder, etc.

Glad your welder works.

EDIT
yes vfd can be "worth it" on certain machines, but it's meant to be a speed control/converter. Wrong application.

 

Properly designed 1/3 phase machines are more efficient on 3 phase


Properly designed would mean the single/three phase output duty-cycle would the same. (IMO) single phase input amps are more..I can get 300 amps, 28 volts out of my LM-200, running off a 15 hp RFC I have. It's more efficient running on single phase input without the rotary making the three phase leg....

 

I hope so.
That was my point that the 1/3 phase units don't loose 2/3's of there power running on single phase.