I have a vertical knee mill with a 3hp 3 phase motor that I would like to power with a VFD, using mach 3 for speed control. It is a 4 pole, 1725 RPM, 8.9 amp unit.
Would I need a constant torque VFD, or a variable torque VFD for this application? What is the difference?
Would the motor lose any power by using a VFD vs. using a rotary phace converter?
I went to
www.driveswarehouse.com and I am a little overwhelmed with the choices. Could someone reccomend a brand / model?
If I understand correctly, I can use the VFD to increase the maximum RPM of my spindle, by increasing the frequency. How much higher would I be able to increase the frequency without risking damage to the motor, bearings, etc...
The head is a variable speed model with a low (60-600 RPM) and a hi range (600-4250 RPM). Would I just leave the head in hi range at the maximum RPM setting, and adjust the actual RPM using the software and VFD, or would I still have to shift ranges to meet speed requirements?