Looking for answers again

[mksj]

All the VFD's I am aware of are 3 wire control for speed control when using voltage, so as Wobblyhand indicated it is just a voltage divider, the resistance value has to do with the current available between the typical 0-10V terminals and the immunity to electrical interference as the resistance goes up. You can use a 10K, but may be some increase jitter on the Hz as one lowers the speed on the pot. Shield grounding when using shielded cable is to ground control and speed cables only at the VFD end, I usually connect the shield/drain wire to the ground screw on the VFD housing. Shielded motor cables if used are a bit different, the shielded is grounded at both ends of the cable. Always put some tape or shrink tube on the exposed shield wire so it does not short to anything. Recommended grounding for the motor cable shield is circumferential clamp/gland where it enters the metallic enclosure or to the back plate ground post/bar in the VFD cabinet, at the motor end either via a metallic gland or to the motor ground lug. Motor cables also must have a ground wire that is attached to the VFD ground/cabinet ground in the VFD cabinet and the ground at the motor end.