Here is a link for connecting the FWD command directly, you can by pass using the relay in the attached G540 DWG.
https://www.cnczone.com/forums/spind...equipment.html
The analogue command is also shown in the manual below.
The 3 you are concerned with on the VFD is ACM (common) , V1 (analogue command signal, and +10v (power).
Al.