VFD for lathe

[dankeenan]

I have a 3hp induction motor on my metal lathe. I only need to run the motor at constant speed (lathe speed is controlled via gear changes). Can I use a standard VFD (non sensorless vector)?

 

[rsanter]

if you use a VFD you can just leave it at 100% to drive the motor full speed. but you may find that you will actually want to make use of the variable speed at least a little bit.
for my mill I use the VFD to do some adjustment of speed. if I need to change the cutter size drastically then I move the belt

bob

 

[dankeenan]

I use a sensorless vector VFD for my mill also (older series 1, so I do not have to change belts). My basic understanding is the sensorless vector allows you to run near full motor output at any speed. I run my mill at 5hz sometimes when I am tapping. I set the belt at one position and only change from high to low.
But on a lathe, I have all the speeds I need via the gear head. If I can save some money, I would rather not spend the extra on the sensorless vector feature.

 

[tdkkart]

You'll REALLY want the variable speed feature once you've used it. Infinitely variable speed is really handy.