PWN Spindle with Openbuilds Blckbox Controller

Hello All, Ive been using a watercooled spindle for a few months on an open builds machine with the Blackbox X32 controller.

But recently I have been struggling to get the spindle to spin at the correct speed as set in software. I also cant get the spindle to stop completely when finished a run. It spins at about 500 RPM. I also cant seem to get a voltage variation on the 0-10V port on the blackbox. Turning the 0-10V potentiometer does not seem to change the measured voltage. I believe all three issues are related.

Any suggestions?
Thanks

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.

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Hello Chris,
Thanks for the reply. I will definitely have a play later this evening and let you know what comes of it. Will also troubleshoot the 0-10V issue in the openbuilds forum.

Thanks

Hello Chris,

So my measurements are as follows:

3k 1.2v. 2370rpm

6k 2.46v. 4800 rpm

9k 3.75v. 7920 rpm

12k 5.04V. 11190rpm

15K 6.3v 14430rpm

18k 7.6v. 17880rpm.

21k 8.97v 21360rpm

24k 10.2v. 24000rpm

My achieve 10V my lowest voltage settles at 1volt

So looking at my voltage mapping they seem to be fine but are not translating into accurate rpm.

It does look how I suspected, low on the low end, high on the high end, and the target area isn’t very far off.

Try adjusting the p2.0.13
not only is it an ignore below, but it also shifts the rpm’s, and that might just do it. Otherwise, I don’t have a good solution. Build Botics, Longboards (that’s a separate issue all together), and Carbide Controllers are notorious for this.

You might also want to entertain modbus connection with the db25 connector.

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