3 phase convertor or VFD?

[rpjind217]

Recently purchased a Wells-Index Model: 520-CEN5 (747-847 base, 700+ CNC manuals) with an M400 controller (Serial: 6577). Currently the shop has a 20hp American Rotary Pro (I think, definitely not a digital) phase convertor that runs a couple of our bigger manual machines. We have heard several comments not to use a phase convertor. Are there any caveats to using this or any other phase convertor? I also reviewed schematic S14731.r2.pdf with thoughts of wiring in a VFD that would power the spindle and pull single phase for the controller but based on what I am seeing in the schematic several components require 3 phase. Would you be able to advise on the situation?

[cncsnw]

I would be very surprised if that machine did not already have a VFD running the spindle.

It is probably a Baldor 18H vector drive, and it might be in a separate enclosure on the back of the ram.

The only other component that might require 3-phase power would be a flood coolant pump. If you have a 3-phase flood coolant pump, and you want to use flood coolant, then you either need a phase converter; or you could install a micro VFD (1/4HP or 1/2HP is usually all that is needed).

[rpjind217]

I will dig in further. We just got it home and when I looked in the cabinet initially, I didn't notice one but I wasn't really looking for that specifically. Thank you for your input. But, in case there isn't a VFD in the cabinet do you think we would be ok with going with the rotary convertor that is already in place? I forget which model we have but I do know it isn't the "digital" unit that I seem to hear some people say it is a must or there would be damage to electronics. Would hate to let out the magic smoke just because.