Got My First Machine!

Unless you can find the other leads and reconnect for 240 I'd suggest going with the VFD.

John & Izzy,

You could use a VFD but it would only power the spindle motor. The rest of the machine would have to be run from a different power source since there are several other motors and at least some if not all, are DC. Actually, I think the rest of the machine could be operated by supplying 230V single phase power to the primary side of the control transformer that's in the electrical control panel. Components like the magnetic starters could be eliminated (or just disconnected). That may be a good way to go. I'll have to think about that some more.

Ted
 
The feed motors would need to be powered separately even if I went with a transformer and vfd setup? so I would power the machine with 460 3phase just as it is I've been calling around and I found a used vfd/transformer set up for 600. But if there's anything cheaper and easier I'm in!
 
The feed motors would need to be powered separately even if I went with a transformer and vfd setup?

The VFD/transformer is only for the spindle motor. The rest of the equipment all seems to be 120V. You could split that off ahead of the transformer, or just run another cord and plug it into the wall. That's what I do.
 
Izzy,

I was just looking at the schematics that you e-mailed to me. What you could do is get a VFD with 230v single phase input and 460V three phase output rated to operate your 4 HP motor. Wire the 460V three phase output from the VFD to the tops of the three fuses designated as FU-2 in your panel (you would discard the existing wiring to and from those fuses). Then disconnect the three wires (T1,T2 & T3) from the bottom heater connections on the magnetic starter and connect them to the bottom side of the FU-2 fuses. This should put your VFD power directly to the spindle motor and utilize the existing fuses to protect the motor. Then you would disconnect the existing wires from the tops of the fuses designated as FU-3 and connect a 230V single phase power source to the top side of these fuses. Then you just need to re-do the primary side wiring on the control transformer and connect it for the 230V input as shown on the transformer. I think that should work. I'll give it some more thought to make sure I'm not overlooking something.

Ted
 
What you could do is get a VFD with 230v single phase input and 460V three phase output rated to operate your 4 HP motor.

Have you got a link to a voltage doubling, 230V input VFD? Be a handy thing to have for some applications, but I have never seen one. I have seen (and used) 120V in, 230V out VFDs

Wire the 460V three phase output from the VFD to the tops of the three fuses designated as FU-2 in your panel (you would discard the existing wiring to and from those fuses). Then disconnect the three wires (T1,T2 & T3) from the bottom heater connections on the magnetic starter and connect them to the bottom side of the FU-2 fuses. This should put your VFD power directly to the spindle motor and utilize the existing fuses to protect the motor.

Normally you don't want anything but wire (or a choke) between the VFD and the motor. The VFD takes care of the motor overload protection.
 
Have you got a link to a voltage doubling, 230V input VFD? Be a handy thing to have for some applications, but I have never seen one. I have seen (and used) 120V in, 230V out VFDs

No I haven't Jim. I guess I was assuming that since they make 120V in / 240V out that there would be a 230V in / 460V out. I guess not ?? So, I guess he's back to needing a step-up transformer if he stays with 460V.

Ted
 
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The VFD/transformer is only for the spindle motor. The rest of the equipment all seems to be 120V. You could split that off ahead of the transformer, or just run another cord and plug it into the wall. That's what I do.
ahh see I was under the impression that I just had to run 460volt 3phase power to it and it would all run the same because of the step down transformer it has for the feed motors I'm glad I've got some help tho I'd be upstream without a paddle!
 
I did a little research and found it is possible to modify some 460V VFDs to make them 230 in 460 out but only up to about 3 hp without extensive modification for the higher HPs
 
ahh see I was under the impression that I just had to run 460volt 3phase power to it and it would all run the same because of the step down transformer it has for the feed motors I'm glad I've got some help tho I'd be upstream without a paddle!

That's what is so great about this forum, we try to keep each other out of trouble. :)
 
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