Electric Motor hook up

Okay I am taking my time setting up my Heavy 10. I have been reading tones of info. One of the things I see talked about is the use of a VFD with motors. I am just wondering why a lot of you guys don't just buy a 1hp or what ever you need in 220v? Also my motor can run on 110 or 220. Which is better? I can hook mine up to 110 and use a variac in line and get just about any speed I want. Has anyone done that? The variac I have goes to 150v and is a 33 amp model.

My understanding of Variacs is limited but I think they work best for applications were the load is proportional to the motor speed like fans and pumps. They reduce the voltage to the motor which reduces the torque available so the motor slows until the load matches the torque. I don’t think they work for all types of single phase induction motors either. You have the motor and variac already so wire it up and try it out and see how it works.

My Heavy 10 came with a 1hp 3 phase motor in good condition. I could have found a single phase replacement for it relatively cheap. Instead I picked up a VFD for not much more and got variable speed, overload protection, low voltage remote switching, reversing, emergency stop... and a bunch of programmable parameters I will probably never use. I really like the ability to slow it down for parting operations and have run it as low as 10hz when required to reduce chatter. Had it come to me with a single phase motor I would be using it, but given the choice of VFD or motor swap. I’d take VFD anywhere adjustable speed might be handy.

Your mileage may vary.

Ben

Use the auto trans and you will BURN the motor up and the var. , an ac motor speed is controlled by the Hz not voltage...Phil

With a single phase motor, if it has capacitor start winding, and you set lathe for highest speed, if you apply too much load and motor slows down too much the centrifugal switch will re-engage the start winding. I had a single phase motor on my last lathe, it worked well 99% of the time, only problem was listed above. Just change your belt/pulley combination for desired spindle speed, its not that hard.