[Bmac25]

Hi all,
Recently purchased a 1996 Bridgeport VMC 760-22 with a DX32 control. I had it delivered and shoe horned it into a two car garage.
now its time to figure out how to power it . It has siemens drives.

1) is it possible to run this machine on 240V single phase?? if yes, what would it take to do it?

2) i have a 20 HP 3 PH motor laying around i could build a RPC with it and balance with capacitor banks. Do you think it would safely run on this?

I didn't spend a lot of money on this machine and would like to avoid spending thousands on something like a phase perfect .

[machinehop5]

...only things 3PH are the Spindle and coolant pump most likely. What Horsepower is the Spindle drive? Model number?

[Bmac25]

I think you are correct, however this unit is more complicated than Im used to, and I really don't want to fry anything. I will try to post pictures of the spindle and axis drives. I believe the spindle is 12 HP.
The drive is a Siemens SIMODRIVE 611: written on it " SIMODRIVE E/R MODUL, INT. 16/21 KW, 6SN1145-1BA00-0BA0".
Next to it is: "SIMODRIVE LT-MODUL, INT. 80A, 6SN1123-1AA00-0AA0

I do have the manuals so i should be able to supply some wiring diagrams if needed, there are many however and id have to find the right ones.

much thanks for responding.

[Jim Dawson]

Yeah, looks like that one is going to need to run on 3 phase. The 20HP motor you have would work fine as a RPC for the machine. Just make sure you balances the phases well.

[Bmac25]

Thank you for replying.
How would you quantify "well Balanced"? The previous 5 HP RPC I made I followed the Fitch Williams design and instructions found online.
Would that be sufficient?

I suppose my next question is which of the three legs on the machine should I hook the generated leg to?

much thanks

[Jim Dawson]

Thank you for replying.
How would you quantify "well Balanced"? The previous 5 HP RPC I made I followed the Fitch Williams design and instructions found online.
Would that be sufficient?

I suppose my next question is which of the three legs on the machine should I hook the generated leg to?

much thanks

The Fitch Williams design is good. I followed those guidelines when I built my RPC to run my CNC lathe. Just measure the leg to leg voltage under load and adjust the capacitance as needed. Mine normally runs +/- 1 volt leg to leg.

There is most likely some single phase in the panel, derived from 2 legs of the 3 phase. You would want to connect the generated leg to the line that is not connected to the single phase hardware.