I wired my Hitachi WJ200 VFD direct to the Masso G3 spindle connections skipping the GX12 connector installed by Onefinity. I didn’t want to deal with buying a GX12 connector and the soldering job. Add to that the connector would hang too low off the G3 touch for my layout.
Thanks to Masso documentation on their forum and input from our expert @Aiph5u here on the forum, I tried both source and sink configurations for the connection. Both worked and I simply kept the last one I trialed in place, the Sink configuration. I have attached the schematic for this below. I took a Masso figure from their forum and cleaned it up a bit for clarity. For a bit of background, you can follow some of the discussion behind this here.
The Masso G3 sends a 0-10 vdc analog signal for the spindle speed. The Hitachi expects a 0-9.8 vdc command. This will result in an error in actual spindle speed (higher rpm than expected, about ~3% in my case). This can be remedied by the spindle setup in the Masso settings by changing the maximum spindle speed to a higher level that removes the error. My Mechatron spindle is 24,000 rpm max but I input a higher number into the Masso setup settings which effectively scales the Masso signal to the needs of the Hitachi.
Be aware that Onefinity doesn’t support spindles and as always, use the work of others at your own risk. That said, here’s the connection scheme and setup I used.
And here’s how I scaled the Masso speed signal to get the output from the Hitachi to produce a correct spindle speed.