I have just bought a CNC6040 with 800w spindle via ebay, chinese import. It seems to be a solid piece of kit, albeit with the limitations one might expect from such a purchase.

Currently the blue box controller supplied has no exposed connectivity to the Huanyang 1.5Kw VFD - and according to the supplier I am supposed to start, stop and control the spindle from the VFD front panel.

Being an investigative sort of person I popped the top off of the blue box controller, and the interface card which connects to the PC via the parallel port is one of these:

Click image for larger version. 

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It's a 5 axis CNC control board. Although you can't see it in this diddy image, on the right are terminals marked as '0-10v Spindle Speed Output Connect Converter'. There are other terminals labelled 'Spindle ON/OFF Control Interface'. This interface can be reviewed on ebay:


It seems to me that these terminals might be suitable for connecting to the VFD. Hoever I don't want to blow things up by making the connection.

I wonder if anyone can advise on this?