Re: ACER WITH NO SPINDLE GEARS: VFD OR 3KW SERVO?
You can get away with a 0.75:1 ratio on the spindle drive with a 3 HP, and with a 5 HP motor maybe even a 0.5:1 ratio, but not a 0.312:1 ratio. But.... You have to use a sensorless vector VFD to drive it. If your VFD is not sensorless vector it won't work for that application. Sensorless vector control will allow near 100% torque down to about 0 RPM
Check your VFD specs and see if says something about ''SVC'' mode, or something like that
Jim Dawson
Sandy, Oregon, USA