Has anyone had constant errors on RS485 using a PWN CNC Spindle? I am using a mic cable that is shielded and grounded only on one side. The cable does not follow the spindle cable, it goes independently between the VFD and the Super Longboard. If I reboot, it will communicate long enough to start the spindle, but then it just constantly errors out after random amounts of time, all of them short. So I know the settings are correct. I’ve got a shielded Cat 6 I may try tomorrow, but wanted to check here with the hive mind first.
Are you sure it is actually grounded? If you have a voltage meter you may be able to check for continuity between ground and what you think is grounded when the cable is connected.
It’s the ground on the RS485 connector in the super longboard. Maybe I should try grounding it at the VFD. Just to try it.
I have the PWNCNC spindle system with the cable from them the plugs into the VFD enclosure for the SLB and once the configuration was right, I had no issues. I do know from experience wiring up a different VFD/Spindle the SLB MODBUS is sensitive to grounding.
It did turn out that I had fat fingered part of my config. 
It’s working great now.