Hardinge bb2v/bb4 mill - VFD setup

I have a Hardinge bb2v mill that I am attempting to setup with a VFD. The mill's motor is a 220V, 3 phase, 3/4 hp (high) 3/8 hp (low). Additionally the mill has control levers for forward, stop, reverse and low speed, high speed.

I purchased a TECO/Westinghouse JNEV-101-H1 which is a 120V single phase input to 220V 3 phase output.

Currently I am planning on running my 120V to a RK5 300V/20A fuse block then directly to the VFD. The VFD ouput directly to the motor, bypassing the Hardinge transformer and motor controls. Then I need to figure out how I am going to create the 0-10V @<20mA as this is what the digital input controler will accept. I think I can set up switching via the mills control levers to toggle on off switches to initiate the forward, reverse, stop, low/high functions on the VFD.

Has anyone here gone through the process of setting up a VFD that allows the original control switches to be utilized?

Anyhow, rather than reinventing the wheel, I was hoping somebody had already gone through the process and could share with me how to best go about the conversion.

Thanks,
T West

The speed control for that VFD I *think* can be implemented
with a simple 10K ohm pot. You don't need to create the
10V supply for that, it's present on the VFD chassis itself.
REad the manual and check to see how they connect a speed
control pot.

The original drum switch setup could be tied into the
VFD low voltage logic circitry. FWD/REVERSE can be tied
to in to the run forward, run reverse logic controls. You
just need to pick three terminals on the drum controller
to create a center off, SPDT switch.

I always thought it would be cool to make the high/low
stick be spring loaded, and use those contacts to operate
the incrase/decrease logic lines on teh VFD.

Use the higher speed setting on the motor, to take advantage
of teh screaming huge 3/4 hp.

Jim

Jim,

Thank you for your reply.
The VFD actually has a pot on it's faceplate that can be configured for speed control.

What I am attempting to do is couple the lever linkages to the vfd to control reverse/stop/forward and high/low. I figure I will set the vfd up at 60hz for high and 30hz for low. What was confusing me was that VFD low voltage logic circuit you were mentioning.

I was assuming i would need a high-low source voltage to trigger the functions in the logic circuit and use the lever to switch them via the drum control.

Thanks,
TW

You need to read the manual on this unit.

My suspicion is, you can implement most of what you
want without any extra add-ons.

Pots are typically conected right between three of the
terminal board points on the VFD, you don't have to use
the pot on the unit itself. It's handy to mount one
remotely near where the operator can get at it
conveniently to change speed on the fly.

The logic controls for forward and reverse are typically
done by conecting a simple switch between a common buss
on the control, and the control line. There's no need
for any external components aside from the switch itself.

The drum switches can be used directly I think.

Jim