Hello, I'm having a difficult time controlling spindle speed in Mach 3.  The Hz it should be running at full power is 300Hz, but when Mach 3 triggers it, it's only going about 20Hz (using the display function on the VFD).  I'm using a C23 breakout board from CNC4PC, and an X200 VFD.  I have it wired in power sink mode, according to their diagram here:

[urlhttp://cnc4pc.com/Tech_Docs/C23R2toVFD.pdf][/url]

It looks like everything is running okay, except for teh speed of the spindle.  Is there a setting within Mach to set the spindle Hz?  I tried motor tuning of the spindle, but that seems to do nothing.  Any guidance would be appreciated.

Barry

Barry -

The only experience I have is that I use an Omron VFD. This is a stand alone unit, with a touch panel on front to control speed manually. It can however be programmed to accept a signal from the computer. This is in the form of a voltage (0-12v) on a control wire. Reversal is a seperate couple of inputs - one on for forward, one on for reverse. If both are on together the thing blows up - no - an error message shows.

The forward / reverse is all controlled by Mach3, the speed is contolled by MachVFM output via a Digispeed, which converts the VFM output to a voltage the Omron can interpret.

1. What does your VFD require
2. Mach can output speed control signals in various ways - have you got Mach set correctly. There are instructions in the manual.