1 and 3 quite possibly are linked, actually most likely. What happens is the controller sends a voltage, the vfd recieves the voltage and converts it to hz. Then you see the outcome in rpm.
I can’t help you with 3, other than you’ll only get 10v when you have 24k rpm commanded for the reason listed above.
1 how far off are we talking. It’s a lot easier if you map it out, so command 3k, what does it read, then jump 3k and report that, all the way to 24k as an example. I would target accuracy for your most common speed with your adjuster.
I would hold off on issue #2 until you solved the 1/3 issue because 2 would fluctuate as you modify the output voltage… but… For issue number 2, adjust p2.0.13. We set it for .1
This is an ignore below this voltage point.
Someone a few days ago with a different controller had to go to .27 because .26 it still spun, so start high and work your way down.