Phase converter etc.

[phantomworks]

Does anyone have an opinion in regards to an American Rotary rotary phase converter 40 HP v/s changing from three phase to single phase via changing the transformer on a 1994 Fadal VMC40 HT CNC 88 HS on the machine? Is one way of powering the machine from single phase better than the other? What are the pros/cons between the two options? It seems most people use a phase converter...why?

[denmar]

All the Hi voltages are 3 phase,(inverter, amp chassis, spindle motor); Fadal used to build single face machines.

[mniadna]

It is far cheaper to use a phase converter, than to have 3 phase service. Initial cost and service cost. I have an American Rotary 25HP converter running my Haas VF-0. The only problem I ever had with it was I connector coming loose on a capacitor, and melting the insulator on the capacitor. They sent me a replacement capacitor and wire, even though the one with the melted insulator still worked. 40HP seems like major overkill for that machine. I just bought a Fadal 4020 HT and have run it off of my 25HP converter. I haven't made heavy cuts with it, though.

[iess525]

What did you end up doing?

I would suggest a single-phase transformer.

[Neal]

Phantomworks--
Although phases converters can present some problems such as unbalanced power and excess electrical noise, may customers are successfully using them.
Running single phase is an option but be aware that you will loose approximately 20% of the machine performance when you do that.
Tough choice to make, I know, but that's the reality of of all.

Neal

[FastFieros]

I have the American Rotary 20HP on my VMC15. Works so good, I can also run a 5HP engine lathe at the same time with no issues.