tuffduck wrote: ↑Mon Aug 09, 2021 8:18 pm
I put PD0011 to 0, it made no difference. I have no idea what you mean by calibrating the VFD or adding a cap. The maximum speed I have set in Acorn is 18000. ShawnM said to put the minimum at 0.
Neither of these made a difference.
I set the MDI at 12000 rpm the VFD read 12512 rpm. The voltage read 6.75 volts. I believe it should be 5 volts. Why?
When you set PD0011 to zero in the VFD did you still have the wizard set at 12000? Both the VFD and the wizard need to be set to zero for minimum speed.
Centroid has a 7 page document on calibrating spindle speed with your VFD and there's a topic for adding the .1mfd cap across the analog output on the Acorn to stabilize the RPM if it's not rock solid at any frequency. I'll see if I can find them and post this info for you.
Here's the link for VFD calibration, it has to do with rigid tapping but it walks you through setting it up for accurate rpm's. They will be close but never exact. The only reason 18000 is exact is because that's the max setting and it can't read what it actually is.
tuffduck wrote: ↑Mon Aug 09, 2021 8:18 pm
I put PD0011 to 0, it made no difference. I have no idea what you mean by calibrating the VFD or adding a cap. The maximum speed I have set in Acorn is 18000. ShawnM said to put the minimum at 0.
Neither of these made a difference.
I set the MDI at 12000 rpm the VFD read 12512 rpm. The voltage read 6.75 volts. I believe it should be 5 volts. Why?
If your max speed is 18000 @ 300 hz on your spindle then 12000 rpm would be 6.75 volts. To be exact 6.75 volts would be 12150 rpm. Here's a speed chart for you for a spindle with a max speed of 18000.