I've had pretty limited time to work on things this week...I hate it when my day job gets in the way of my hobbies.
I've mostly been working on getting the UC300ETH/MB2 to talk to the Hitachi VFD. I connected the C motor step output (CS+/CS-) to the EA and L pins on the VFD as 1Jumper10 did. I used the NO output on relay 2 from the MB2 as the M3 signal from UCCNC to actually switch on the spindle. After a few things not quite working, I found the errors in the VFD settings and was able to turn the spindle on from UCCNC.
I have the speed running theoretically right, but the numbers I had to use in UCCNC don't make a lot of sense to me. Like 1Jumper10, I ended up using 62.5 steps per rotation in order for the UCCNC spindle speed setting to scale correctly as RPM. The VFD supposedly scales 32kHz to the maximum frequency setting, which is 400Hz. 24000 RPM is 400Hz (24000/60= 400), so I would expect to see a factor of 4/3 in there somewhere (32000/24000). It might have something to do with the axis C settings in UCCNC. At any rate, it works, so I'm not complaining. I do need to try to check the actual spindle speed to confirm it, though.
I also bumped the accel and decel times to 2 seconds each. I didn't find a point where the VFD gave me any errors, but that seemed about fast enough. I didn't turn on any of the DC voltage braking or add a braking resistor. I think the inertia is low enough that the VFD can handle it. It won't be continuously speeding up and slowing down, so good enough as is.
I forgot to copy my VFD settings, but I will post the changes from default values with some explanation in the next couple of days.
Thanks again for the help 1Jumper10! It made things a lot easier!
Robert