3 phase to single phase

[fencemaker]

I recently bought a older big Miller mig machine with millermatic wirefeeder that came out of a manufacturing plant. Its not been used a whole lot and runs great ...... on three phase power which is where my problem lies. The price I paid made it well worth the purchase, even if I were to just scrap the copper. But I only have single phase power and would much rather use it. I need to know the RIGHT procedure to convert it from 3 phase to single phase.I know this will probably loose some duty cycle but that is ok since I'll only use it for general fabrication. I know there are phase convergers but didn't know if that was the best way. Thanks for the help!

[Cgotto6]

Rotary phase converter

[cruizer]

And what machine did you buy, no esp here. Basically no way to use a 3 phase only machine on single phase for starters. You need a digital phase converter. Rotarys are not the best idea on a welder

[weldbay]

The cheapesy way to make a phase converter is to buy a single phase motor and a 3 phase motor, use the single phase motor to turn the three phase motor and generate the third leg for you mach. Not cheap but any good elec,. not me, can show you or look on the net.

[cruizer]

The cheapesy way to make a phase converter is to buy a single phase motor and a 3 phase motor, use the single phase motor to turn the three phase motor and generate the third leg for you mach. Not cheap but any good elec,. not me, can show you or look on the net.

Lathes and other non circuit board machines don't mind the rotary converter, Welders do not work well on this system , thus its NOT recommended. The only way to do the conversion is with a Digital phase converter

[weldbay]

Lathes and other non circuit board machines don't mind the rotary converter, Welders do not work well on this system , thus its NOT recommended. The only way to do the conversion is with a Digital phase converter

Is it me or what. the mach is old so probably not an inverter but a transformer welder. I have used rotary inverters in my welding repair 1-phase shop for years,

Here is how you do it:
http://www.metalwebnews.com/howto/ph-conv/ph-conv.html

[caddidaddy55]

What model is the welder? If the primary on the transformer is "8" wound you can convert it to single phase. I did this to a CP-200 using the info i found here http://www.practicalmachinist.com/vb...-phase-199832/ and it works well no loss of power and no external converter. Cost around $100 to convert.

[cruizer]

Yes, it would have to be an old welder with diodes NOT scrs and NOT using circuit boards. for instance the above, or a SRH stick welder.

There are ways around things. However, from my point of view. I chuck the old machines like the CP200 and such as they have zero worth to me. I do keep the feeders though

[kevin]

Cruizer, you just got me thinking, in 1986 i bought a gold star srh 300 amp 3 phase machine, it sits in my storage trailer, what a great welder, i am 2500 feet from the 3 phase lines, is it cost effective to do what you just suggested, and if so, do you have a ball park cost for this adventure. Thanks kevin

[cruizer]

Nope that unit has a circuit board firing scrs, providing its a "Goldstar". The SRH and Goldstar do the same thing (DC stick), but are different animals.