I'm hooking up a VFD to my 1961 vintage 9" South Bend lathe (with .5 hp,
208 vac, 3 phase motor) and I have a few questions.
I can hook up an external pot to control the speed of the lathe. The
specs says the pot has to be between 3K - 5K ohms. What would be the
difference in operation if I were to use a 3K ohm pot vs a 5K (or vice
versa)?
What would be a reasonable maximum speed for the motor? The nomenclature plate says 1725 operating rpm, but I understand with a VFD you can go much higher. I don't want to hurt the motor, but the extra speed would be nice when using carbide. I've also got the ramp up and deceleration speed currently set at two seconds; is this reasonable?
I knew nothing about VFD's when I started the installation (I'm still not quite finished), but I have to say that it sure seems slick. Not sure of the advantages/disadvantages of using a VFD compared to a static phase converter (which is what I was using before). I understand with a static phase converter you lose 1/3 of your horsepower, not sure if the same thing happens with a VFD. I'm hoping not...
Thank you!
Dave Young
What would be a reasonable maximum speed for the motor? The nomenclature plate says 1725 operating rpm, but I understand with a VFD you can go much higher. I don't want to hurt the motor, but the extra speed would be nice when using carbide. I've also got the ramp up and deceleration speed currently set at two seconds; is this reasonable?
I knew nothing about VFD's when I started the installation (I'm still not quite finished), but I have to say that it sure seems slick. Not sure of the advantages/disadvantages of using a VFD compared to a static phase converter (which is what I was using before). I understand with a static phase converter you lose 1/3 of your horsepower, not sure if the same thing happens with a VFD. I'm hoping not...
Thank you!
Dave Young