Centroid Community CNC Support Forum

Hello,

Questions:
1. When I plug in the acorn the spindle begins moving immediately at about 1hz speed (60hz motor). Once cnc12 comes on (and recognizes estop), spindle stops. After homing the machine (click cycle start), the spindle begins moving again at around 1hz output. What would cause this?
Note: If I play around with the manual spindle cycle start/stop high/med/low and reverse, and turning spindle on and off, some combination actually stops the spindle altogether which is desirable.

1a. I did the spindle bench test before I hooked everything up and punched in the values as asked by cnc12... however I DID change the spindle speeds in the wizard after I did this. Would this have an impact, and should I redo it? If I redo it, should it be with spindle com and 0-10v wires disconnected?

2. I have noticed that after I disengage estop, I don't have axis control right away, clicking the on screen job buttons after about 5 seconds the axes are now enabled and can move. Is that normal?

3. See background, this is second acorn after swap out program. I did not perform 'stress test' a second time. Should I? In the installation manual it shows everything but the power supply and ethernet disconnected. If your coaching says to run it again, can it be done with all the i/o connected? Otherwise I think I will have to reset cnc12 because it expects estops and homing prior program run.

Bonus questions
3. I had some odd behavior earlier where when the acorn was booted and cnc12 running both axes en 1 and 2 were green. Clicking an axes jog would then disable them. On a whim, I disconnected all the shielding wire from all inputs/outputs from the control box ground. I did this because it seemed to be the only commonality between the two, and also I did not encounter this pre hookup of wire shielding to chassis ground. This did end up fixing the 'issue'. But now my control wiring is not grounded (I only grounded on one side). Is there any advice?
^Questions 1 and 2 is the current state of the machine + unhooked shielding wire.

Some background:
I am on acorn number two from the swap out program, after inadvertently connecting an incompatible VFD (see other thread of mine).
I have since purchased and setup a new vfd and got it working. It is setup / wired the acorn as depicted in the acorn rev 4 for the huan yang vfd precisely as shown. Using other threads I was able to get vfd up and running without acorn (just local control via a battery and switch to run forward.

VFD manual: https://www.nvcnc.net/wp-content/upload ... Manual.pdf

I appreciate everyone time in advanced.
I will be continuing to read thru the installation manual and searching around in the meantime

Thank you

Bump, thank you!

Blitz355 wrote: ↑Tue Nov 26, 2024 9:26 pm Bump, thank you!

You will have more chance of getting a response if you post a current REPORT.ZIP

A report would make answering these questions much easier. I would also appreciate some pictures of the VFD wiring, the Acorn wiring, and the cabinet as a whole. If you followed one of our schematics, mentioning the drawing number would also help us give more useful answers.


1. Somehow the spindle is enabled and is getting some kind of command to move. This could be one of many things including: one of the direction inputs is wired to the NC terminal on Acorn's output relay, incorrect parameter settings on the VFD, or some other things that are less likely. The low output frequency could be from an offset or noise on the VFD's analog input. To deal with the noise, I would suggest the third circuit mentioned in this post.

1a. If it worked correctly, I don't see how changing the speeds in CNC12 will make it stop working. Should be fine to continue without spindle bench test.

2. 5 seconds seems pretty long. On the Wizard Axis Configuration page, what is "Drive Enable Delay" set to? The default is 250 milliseconds.

3. You can make notes of the i/o assignments in the Wizard, remove the assignments, and then unplug everything. You could also just save a report, remove the assignments and unplug everything, run the stress test, then restore the report to have everything back to normal.

Bonus 3. Grounding wire and cable shields on one side should be the default case for most purposes. This helps prevent ground loops which can worsen interference. Of course, if a device's manufacturer recommends connecting both ends, they probably have a reason for it. Grounding is a complicated subject that I am still working on understanding myself but the conventional wisdom is to make the ground connection on the side that is sourcing current. Your control box PE should be at the same potential as the machine chassis.

centroid467 wrote: ↑Wed Nov 27, 2024 10:45 am A report would make answering these questions much easier. I would also appreciate some pictures of the VFD wiring, the Acorn wiring, and the cabinet as a whole. If you followed one of our schematics, mentioning the drawing number would also help us give more useful answers.


1. Somehow the spindle is enabled and is getting some kind of command to move. This could be one of many things including: one of the direction inputs is wired to the NC terminal on Acorn's output relay, incorrect parameter settings on the VFD, or some other things that are less likely. The low output frequency could be from an offset or noise on the VFD's analog input. To deal with the noise, I would suggest the third circuit mentioned in this post.

1a. If it worked correctly, I don't see how changing the speeds in CNC12 will make it stop working. Should be fine to continue without spindle bench test.

2. 5 seconds seems pretty long. On the Wizard Axis Configuration page, what is "Drive Enable Delay" set to? The default is 250 milliseconds.

3. You can make notes of the i/o assignments in the Wizard, remove the assignments, and then unplug everything. You could also just save a report, remove the assignments and unplug everything, run the stress test, then restore the report to have everything back to normal.

Bonus 3. Grounding wire and cable shields on one side should be the default case for most purposes. This helps prevent ground loops which can worsen interference. Of course, if a device's manufacturer recommends connecting both ends, they probably have a reason for it. Grounding is a complicated subject that I am still working on understanding myself but the conventional wisdom is to make the ground connection on the side that is sourcing current. Your control box PE should be at the same potential as the machine chassis.

Drive enable delay is set at 250ms still

Report attached!
Will edit with images of wiring.... go easy on me. This is 1000% cleaner (and swapped to shielded cable) than what the previous owner had... Still an opportunity to clean up.
Note, VFD side and control wiring shielding is grounded on the vfd side. Stepper drives and inputs (estop, etc) shields are grounded to chasiss in nthe box near the acorn.

Vfd schematic: s14984.def

I don't see anything that stands out in the PLC or parameters. Wiring looks ok as far as I can tell from the pictures.

It is odd to have it set to G99 mode by default with no spindle encoder.

I will try to follow some of the advice earlier and redo stress test and spindle bench tests again. See what I can figure out.