Denford Novamill Mach3 conversion

**irving2008** · 17-10-2014

All commercial VFD control inputs are referenced to signal ground, which shouldn't be confused with safety earth. The AC input and UVW outputs are isolated/floating.

The VFD has effectively got a low pass filter on the speed control inputs as it has a limited slew rate on speed. You could add an external capacitor but it's not needed.

**EddyCurrent** · 17-10-2014

Originally Posted by irving2008

The VFD has effectively got a low pass filter on the speed control inputs as it has a limited slew rate on speed. You could add an external capacitor but it's not needed.

Irving, are you referring to the ramp settings here ? which basically use a capacitor integrator. I say this because some drives can trip on overcurrent if the ramp is set too low which implies the input itself is not filtered.