Hi,

I am working on a VDF lathe with a Fanuc 6T that had a dc spindle drive. The drive failed so it was decided to replace it with an Emerson VFD. We have it all in place and mostly functioning with one area still left to sort out. BTW the drive is commanded by a +-10 volt output from the Fanuc.

When an M03 or M04 is called with a speed of zero the spindle keeps turning CW at about 20 rpm. I have tried adjusting parameter 119 which will bring the spindle to a stop, but then the speeds in M03 and M04 are shifted by a similar amount. (M03 runs at about 80 rpm and M04 runs at about 120 when a speed of 100 is called).

I have tried doing an offset in the vfd but I end up with the same result.

Any ideas?

Thanks,

Ron