I am utilizing the 10 volts from my BOB to the VFD. If I control the speed from the VFD I can get the proper top speed of 24,000 rpm, but going thru Mach I can only get about 20,000. I know it’s going to be something simple, but I can’t find it. Any suggestions would be appreciated.

Thanks, Jim

Does your VFD have adjustment parameters to allow tuning of output speed relative to input voltage?

It very possibly does....but I wouldn't know where or what to look for. I am using one of those Huanyang VFDs, so if you (or anyone) have a clue where to find those (if it has it) please let me know.

Thanks again, Jim

Do you have the pulley speeds set correctly?

The pulley setup is:  0   24000   1

Have a look here --> http://www.machsupport.com/forum/index.php/topic,18580.0.html

Worked for me!

Or it that's not applicable, there was a parameter in my VFD that was limiting the max speed.  I had troubles going past a certain RPM until that was set.

If you could find/remember that parameter, that might help my problem.

Good luck and thank you for your response.

I do not have that brand of VFD, so I can not help you specifically.  For the VFD I used to be controlled by Mach (a Fuji), it was the "Base Frequency" that was the problem.  It was set to 60mhz as default and it needed to be set to 300mhz.  300 is what jived with my spindle nameplate (a Teknomotor), so your mileage may vary.

Just had a quick look at the manual for your VFD.  Try changing parameters PD004 (maybe PD003 also).

http://www.2shared.com/complete/tvddak-F/HuanYang_VFD_user_manual.html

Thanks for the info.....................