Need Help!- WEG CFW10 VFD Some Help.

[Cartierusm]

I have a BP clone with a 2 HP 3Ph motor. I've had this VFD hooked up for a couple of years. Works great! When I switched over from a static phase converter it ran so smooth it wasn't funny.

So now the questions even though it runs good I really don't understand all the functions. Their names are a little cryptic for me. I've talk to the rep a few years ago and the settings he had me change made it worse.

Here is a link to the PDF http://www.wegcatalog.com/pdf/br0899.5034.pdf

I was under the impression this was a 'constant torque' model, what ever that means. I thought it would mean it would adjust the frequency to keep it at the correct RPM, but at low speed cutting large holes it sometimes faults and resets becuase the spindle stops.

So I'm doing a CNC conversion on this mill right now and want to know what wires I'm supposed to hook up to a CNC4PC C11 to make Mach3 Control it? Next what settings in Mach need changing? And what settings to change in the VFD to make it run optimally? Also how does mach know what RPM it's running at as when I bought it, it doesn't have a conversion settting. I had to use a handheld tachometer to figure out what the different numbers were.

TIA.