VFD Wiring Help?!

[jarrettbailey]

Hey everyone!

I finally got a lathe and a mill for my home shop and I bought VFD's to use them on 220 1ph. The mill I believe is more straight forward since it's just forward and reverse and the switch for it is easily accessed. I'm unsure of how to approach the lathe though. It's got a foot brake (brake is mechanical), forward, reverse, on, and off switches. I've not been able to find diagrams for this and I don't have (nor can I find) a manual for this lathe. Does anyone have any ideas or can you point me in the right direction. I'd like to simply use the lathe as though it was hooked to 3 ph power. I am not concerned with variable speeds or anything. I just want to use the functions of the lathe as they were originally designed.

Thanks in advance for the help!

 

[ErichKeane]

SO you cannot have a switch in between the motor and the VFD. Typically you just wire these to the inputs of your VFD, then program in the features you want. You'll basically just want to gut the electricals of the lathe, and wire the switches to the VFD inputs.

In my case, I have a 3 position 'knob' that I use for fwd/reverse as well as 'on/off'. I don't know what your panel looks like, but I'm sure you could use the existing knobs/buttons as inputs to a programmable VFD.

 

[tazzat]

You cant use the lathe as though it was hooked to 3 ph power using a VFD..

 

[pacifica]

Hey everyone!

I finally got a lathe and a mill for my home shop and I bought VFD's to use them on 220 1ph. The mill I believe is more straight forward since it's just forward and reverse and the switch for it is easily accessed. I'm unsure of how to approach the lathe though. It's got a foot brake (brake is mechanical), forward, reverse, on, and off switches. I've not been able to find diagrams for this and I don't have (nor can I find) a manual for this lathe. Does anyone have any ideas or can you point me in the right direction. I'd like to simply use the lathe as though it was hooked to 3 ph power. I am not concerned with variable speeds or anything. I just want to use the functions of the lathe as they were originally designed.

Thanks in advance for the help!

I can understand wanting to keep it simple but a VFD has a number of functions you will want to use on a lathe, i.e. : slow startup, very slow speeds (less than 25 rpm) for threading or tapping, dynamic braking, infinite variable speed to eliminate cavitation, higher rpm's.

 

[markba633csi]

Sounds like you might want an RPC for the lathe instead?
-Mark

 

[ErichKeane]

I can understand wanting to keep it simple but a VFD has a number of functions you will want to use on a lathe, i.e. : slow startup, very slow speeds (less than 25 rpm) for threading or tapping, dynamic braking, infinite variable speed to eliminate cavitation, higher rpm's.

Oh yeah, the VFD is vastly superior in a number of ways, I wouldn't do anything else on any single-motor device. You can still use the standard 'control panel', you just have to wire the switches up as sensors instead. Another thing the VFD can do (which I LOVE) is an emergency stop. I can stop my lathe in about 1/10th of a second (I actually wasn't brave enough to put it lower than ~2/10ths for testing, since it was a violent stop) in the event of an emergency.

Also, my lathe shipped with the option for a 1700 rpm motor OR a 3500 rpm motor. Since I have the VFD, i can do both

 

[Cadillac]

You cant use the lathe as though it was hooked to 3 ph power using a VFD..

what would be the reasoning behind your thoughts? A vfd can absolutely power a 3ph lathe or anything else within the specs of the motor and vfd. Have 4 of them powering a lathe,Bridgepor, and two surface grinders.

 

[tazzat]

what would be the reasoning behind your thoughts? A vfd can absolutely power a 3ph lathe or anything else within the specs of the motor and vfd. Have 4 of them powering a lathe,Bridgepor, and two surface grinders.

Not the way he wanted to use it.. use the VFD as a 3 phase line in and run the lathe as stock using power/stat/stop on the lathe not connecting this up to the VFD

 

[markba633csi]

Right, using the lathe as stock which opens/closes the motor wires is a no-no with VFD drives, but OK with a rotary phase converter
-Mark

 

[jarrettbailey]

Well, I got it going! Wired the fwd/rev handle and the brake switch as an e-stop. Pretty pleased for now. Need to run it a while before playing with other features of the vfd!