Centroid Community CNC Support Forum

Retrofitting the latest and greatest Oak Controller with CNC12 onto a hi performance desktop VMC. It has a Swiss TMD 30k rpm spindle and Yaskawa spindle drive configured to run at 20k rpm, original configuration. No spindle encoder. 3-wire operation run forward & reverse with analog command. Signals from Yaskawa to Oak are 'At Speed', 'Zero Speed', and Drive Fault. Set Oak spindle configuration to 20k rpm to match original setup. When Spindle reaches commanded rpm, have not run faster that 1000 rpm, 'At Speed' is asserted, Oak sees it and RPM on screen shows commanded rpm. Then spindle speed starts varing: the on screen rpm indicator goes on and off as 'At Speed' signal fluctuates. The speed fluctuation is not due to the Yaskawa Drive, I can see the command voltage from the Oak analog output varing. If I use a straight-in DC command voltage no fluctuation. Also no problem when run from Spindle Drive Local Control, its rock steady.

Any suggestion on what we missed in setup or spindle configuration.

thanks much.

Problem may be resolved. Reset Yaskawa spindle drive to factory defaults. Reloaded parameters which included the oem's 'User Defined V/F Profile'. Spindle appears to run smoothly @ speed. Only tested up to 10k rpm both M3 & M4.

Correction: said 3-wire operation, it is actually 2 wire operation.

Still testing thanks.