Can someone explain P 78 in practical terms for me? This happens on several lathes for me, so I'm curious as to the behavior why. Here are some conditions:
Do you get correct spindle speed response with P78 = 0?
Does the error (running too fast) happen with P78 = 3? What about with P78 = 5? Perhaps we can narrow down which specific feature is adversely affecting the spindle speed commands.
I set P78 to 0,1,5, etc, but that didn't help much.
I think the issue was that the min/max spindle speed is what determines the 0-10v scale, (in Setup - Motor). I was hoping it was smarter than that. If there's a parameter we can adjust to slave the 0-10v to the encoder pulses, that would be a lot cooler. I also have a problem with the wording on the min/max, since it's relative to high gear. (This particular 100hp machine is certainly capable of spinning its 88" chuck at 500 rpm, but no way would I want to be near it).
So here's a tip for those in the future looking for why this occurs: If your spindle drive has a max RPM setting at 10v, that's exactly what you need to have in the motor setup. It appears that spindle encoders are only used when they are in a slaved operation (like threading).