CNCEST 6040 USB loose wiring

Hi all

I received my 6040 yesterday and have set it up and all axis are moving from Mach3 but I cannot get the spindle to control from software. I have read through quite a lot of posts from other owners with similar or the same problem but none of the solutions have worked for me. I decided to open up the control box to look for any loose wiring and found a wire from the VFD board to the BoB loose when I checked the connections.
Now I'm not 100% sure where it should go.
It's a black cable that's connected to the COM terminal of the VFD board and I think should go into the ACM terminal of the Bob. Assuming this is the PWM signal from the Bob to the VFD to contol motor speed which could explain my problem.

Any advice greatly appreciated.

So, after finding some documentation for the RnRMotion board I terminated the cable back into the ACM terminal which is the ground for the 0-10v output. This didn't resolve my issue of not being able to control the spindle. I spent another few hours searching forums and found a post on Machsupport that showed a configuration page within Mach3 for the RnRMotion plugin. There is a spindle setting and a checkbox for Multi-Step Speed, I checked this and the spindle will now kind of operate from Mach3.
When you click on the Spindle CW button the VFD indicator changes from stop to run and I can select a speed from about 30% to 50% and from 90% to 100%. Anywhere in between and the spindle turns off and the run light goes out on the VFD. The VFD display still registers the frequency setting changing as I click to increase the speed by 10% in this 'dead band'

Frustrating to say the least, but at least I am making progress. Any ideas anyone?

Did you get this figured out? If not, what are your VFD settings?