mach3 turn +vfd+cnc4pc spindle card (c6) still not gettings rpms by s word

[jasminder]

friends,
i just build a cnc lathe with a turret and now wanting to add threading support to it. I have a cnc4pc c6 spindle speed controller card, a delta vfd and a nice 3phase motor with 1370 rpms. but i am failed to set the mach3 to run the spindle at a demanded rpm.
here is my experience:

i connected the cnc4pc card to the VFD 0-10V input, a relay to the VFD for enabling the spindle, a spindle sensor for index pulse to mach3 and a different 12V power source for c6.

When i run the spindle on mach3 with something like m3 s600, the spindle rotates at 900 rpms. When i put another value like 1200, the spindle gets some other speed like 1500 or other. I have tried running the spindle calibration wizard several times but no luck. Actually i just don't under stand what the spindle pulleys are and how to set the pot of the cnc4pc card.
My motor runs at 1370 rpms max and the spindle at 1880 max (when the vfd has max freq (50hz). So the ratio is 1.370.
i tried configuring the the spindle pulleys and spindle motor tuning in mach also but i got my hairs pulled out after trying for a whole day.

Can anybody please help me in configuring the vfd with mach3 turn for threading. Any links or step by step guide will be better.
the rpms of the spindle are very stable (within +-2) it means that vfd and cnc4pc card is working well but something is wrong with the setup.
I will post some videos of the lathe with turret soon.

thanks,
jasminder singh

[ger21]

I think you should have Pulley #1 set from either 0 to 1880, or 0 to 1370. Just a guess, though. Have you tried those settings?

[Simon C]

Duno if you already know this but the max speed setting in the mach pully set up is for you to put in your max spindle speed not max motor speed, also need to enter the gear ratio bettween your motor and spindle. hope this helps.