More research done on the speed setting. 0-10volt from the controllerboard to the VFD is now ok but the speed is a bit off. At 4.97volt (50% or 12000rpm in mach3) I read 13000rpm with a tachometer and the VFD indicates that by frequency as well. I just have to setup the VFD correctly to receive the 0-10volt as a 0-400hz signal now but I can't find the manual for the VFD so it's hard to figure out the settings.. Can anyone help me with a manual for nowforever d100 VFD? It is not the same as the e100 manual and the parameter settings is not the same so I can't use that manual..