View Full Version : Converting a Roto-Phase for use with a CNC....

05-18-2007, 12:54 PM
So, I am looking at purchasing a couple CNC's for my shop. One is a SuperMax Max-1 Rebel VMC, 7.5 HP spindle, and the other is a SuperMax TC-2 lathe, with a 10HP spindle. I live out in the sticks, so 3ph power is about 4 miles away.
I currently have a Johnford SV-40, 15hp spindle. I am running that off of a Phase-A-Matic that I got from MSC (IIRC). I've had zero problems with it.

Someone locally is selling two 15hp Roto-Phase (that's the brand) converters.($900 each) They do not have any voltage regulating stuff on them. I called up Arco (the mfg.) and they said they were good for around 7% variation. I asked if it was possible to install a voltage regulator along the line, and power a CNC. They said absolutely not!

Now, I'm not an electrician by any means. I took me a LONG time to wire up 3 geckos to power my CNC router I built 5 years ago. Not much has changed for me since then.

Common sense tellls me that they are just trying to get me to buy a new unit...

What say you?

My Phase-A-Matic has a seperate voltage regulator. This can be purchased seperately from the actual converter. Any reason why I can't use that on the Arco? A local distributor can get the regulators for aroung $800 for the 15hp model.....

05-18-2007, 02:05 PM
Really need to know what technology the regulator is, Active (electronic), Passive etc. And where in the line it is installed.

05-19-2007, 08:48 AM
Well, like I said, I'm no electrician. Hope these pictures explain everything....





05-19-2007, 10:34 AM
Looks as though it is a simple choke or inductance connected from the artificial phase to one of the main feeds, I cannot see it being a problem as to what kind of convertor you use.
With a RPC, they are usually optimally tuned for best power factor (efficiency), this may be being used for this purpose.
There are alot of RPC's running CNC equipment.

05-19-2007, 11:58 AM
Now, that is my current setup.
What I want to do is get 2 more that don't come with voltage regulators, get identical regulators like the one I already have, and presto, CNC rated RPC's...