Thread: RFD Requirements and single phase circuit

I need some help determing the rfd size to run haas SL10 BB 20HP machine. The power requirement for the machine 208-240vAC @ 50Amps 3phase. What will the single phase requirement?

"The power requirement for the machine 208-240vAC @ 50Amps 3phase. What will the single phase requirement?"

1.732 times the the three-phase requirement.

Assuming that 50 amps is the feeder rating, the actual current would be 80 percent of that, or 40 amps, maximum.

The correspondng single-phase amps would be 69.28 amps.

The single-phase feeder rating would be 69.28/0.8 = 86.6 amps, minimum.

Figure on a 100 amp feeder for the machine.

Thanks on input of single phase requirement. What size RPC to due recoomand?

With a 100 amp feeder, you could install a 20 HP RPC.

Thanks for the help, one last question. Recomandation of a RFC brand. Most of the manufactor webs sites say that a lathe is hard start, therfore you should double RFC hp by factor of 2. A 20HP lathe would require a 40HP rfc?