Phase Converters for Powering CNC Routers

CNC owners report good success with using phase converters to provide three-phase power to their equipment. November 14, 2009

I'm getting set up for new CNC equipment. Does anyone run their spindles and vac pumps on a phase converter? I have some small tools that I am using converters for, and have no trouble. Power company wants a bunch of money to bring it to my building.

Forum Responses
(CNC Forum)
From contributor T:
We have been running our complete shop with a phase converter for the last 23 years without any issues. We are running moulders, saws, grinders, etc and our 5/10 Multicam with a 20HP vacuum pump. We have the same power issues, as the electric company wants 40K to run the poles and wire for 3 phase from just down the road. We have been running Kay Industries Phasemasters with no problems.

From contributor B:
Check the inverter for your spindle. Some of them can input single phase or 3-phase power. Mine is one of these. However, if you run it on single phase you will be running the spindle at about 1/3 full power. For me this was never a problem with my 10hp HSD spindle.

From contributor R:
I run my complete shop off of a Phase-O-Matic R90 with no issues. My Busellato CNC and vacuum pump along with all of my other machinery work great. I back feed a 3 phase panel with a central stop/start station in the middle of the shop - makes things simple.

From contributor U:
We used to run a Kay Industries rotary phase converter in our shop. Now we us a Phase Perfect digital converter, which is much more efficient, 97%, than rotary phase. It also uses less power at rest than rotary. The biggest advantage is the balance voltage between all three legs. This is great for CNC.

From contributor O:
I worked in a machine shop a couple years ago that has a converter on every machine - 19 of them - with no problems. But the trouble you will have is that they run hot. They are your enemy in the summer but they are your friend in the winter. We didn't have to run the heat during the day in winter, so it saved on fuel bills, but in the summers (when it gets to be 80 degrees outside), it's nearly unbearable inside the shop. You know how metal expands with heat, so you have to have an inspection room set for 68 degrees to cool the parts for inspection. Sometimes the heat is a problem for the machines as well. But each machine has its own built-in air conditioner for the cabinet, which helps a lot.