[bluecon]

I have a Fadal 3016HT with a 15hp spindle motor.
I will be running this with 240v single phase into a rotary phase convertor.
Anybody know what size rotary convertor to use?
Any recomendations will be appreciated.

[Geof]

http://www.cnczone.com/forums/showthread.php?t=42273

[Al_The_Man]

There has been a general custom that a RPC operating mainly 3 phase motors directly that you can supply 3 phase motors up to twice the rating of the RPC as long as the largest motor fed is not larger than the RPC.
This is because any 3 phase motor on the RPC 3 phase is contributing (generating) to the artificial three phase.
If you have any 1 phase control circuitry, endevour to connect it where possible to the 240 1 phase supply and not the artificial leg.
Al.

[bluecon]

Thanks guys. I am a controls engineer in the automotive business and more familiar with robots and PLC's. They have a large number of large CNC machines in the local Ford plant that machine about a million cylinder heads per year but I have not worked on them. I am helping Rob Jerico set this up in his shop and just wanted some advice from experienced people. American Rotary recomends a minimum of 30HP.

Al, when rating the motor do I need to take into account startup current? I also have the 3 DC drives for x,y,z. Do I need to take these into account.

The shop will also have a manual mill with a 2hp 3ph motor and a lathe with a 2hp 3ph motor. I guess your saying that these will also run off the RPC. Do I need to worry about them sending noise back thru the lines and affecting the CNC?

[Al_The_Man]

Al, when rating the motor do I need to take into account startup current? I also have the 3 DC drives for x,y,z. Do I need to take these into account.

The shop will also have a manual mill with a 2hp 3ph motor and a lathe with a 2hp 3ph motor. I guess your saying that these will also run off the RPC. Do I need to worry about them sending noise back thru the lines and affecting the CNC?

Depends alot if the servo's are 1 phase fed or 3 phase scr etc.
Transformer input machines require a different approach to primarily 3 phase motor loads, every application is different so often it is a question of assessing a particular setup.
If you have machines where the servo's and control is single phase, and it is ensured that they are on the two main 240 1phase legs, you should escape alot of problems.
Al.