Centroid Community CNC Support Forum

Just to be sure, when you go into the PID screen, when facing the motor shaft, and turning it Clockwise encoder count goes up (positive) when turning counter clockwise, encoder count goes down (negative)

Interesting. This says that DMM servos use a convention opposite that of Yaskawa and (I think) Delta; opposite Centroid's DC servo motors; but the same as Centroid's AC motors used with the SD-series drives. Not that it matters much as long as a command for positive movement results in positive encoder counts coming back; but it is nice to have some predictability for troubleshooting.

cncsnw wrote: ↑Mon Jan 20, 2020 5:43 pm

Just to be sure, when you go into the PID screen, when facing the motor shaft, and turning it Clockwise encoder count goes up (positive) when turning counter clockwise, encoder count goes down (negative)

Interesting. This says that DMM servos use a convention opposite that of Yaskawa and (I think) Delta; opposite Centroid's DC servo motors; but the same as Centroid's AC motors used with the SD-series drives. Not that it matters much as long as a command for positive movement results in positive encoder counts coming back; but it is nice to have some predictability for troubleshooting.

Hi Marc, you made me run out and double check.
Yes when facing the motor shaft turning manually clockwise, the encoder count increases. Counter clockwise, the encoder counts decrease.
Jogging any axis in the positive direction, the motor shafts turn clockwise and of course, encoder counts increase and vice versa.

Marty

All,
I Teamviewered into OC customs machine. It does move under control however after 1 turn, it throws a position error in cnc12. I see the encoder counts but I also see the error count go up at the same time. One strange thing I noticed is the Z encoder index pulse appears randomly and flickers. I think this might be confusing the software causing the error count??? OCcustom has an O scope and is going look into the encoder signals.

AcornJosh wrote: ↑Tue Jan 21, 2020 10:14 am All,
I Teamviewered into OC customs machine. It does move under control however after 1 turn, it throws a position error in cnc12. I see the encoder counts but I also see the error count go up at the same time. One strange thing I noticed is the Z encoder index pulse appears randomly and flickers. I think this might be confusing the software causing the error count??? OCcustom has an O scope and is going look into the encoder signals.

There is an issue with shielding the Oak-> Dyn4 cable I found with a previous cable that DMM made. It was fixed.
He does not answer me. DID HE buy the cable from DMM or did he fabricate his own?

I had to tie the data shield ground of the Centroid flying lead cable to the DB25 and DB9 connectors to eliminate this problem
My hunch is he has the same problem, but until he takes pictures of his wiring or describes his wiring more. We can't help him.

Marty

with my Oak/DYN4 setup I had to swap pins 3 and 5, 4 and 6, 9 and 11, 10 and 12 on the communication cable at the oak end. Encoder A+,A- B+,B- to satisfy the requirements in the Oak installation manual on pg.40 (encoder absolute must count positive spinning shaft CCW looking from motor drive end) Both axis cables needed swapped. Not sure if it was really needed, but at the time it was the only way I could find to comply with the Oak setup manual

To invert an encoder to change the + rotation direction, you need to swap A+ with B+ and A- with B-. No changes need to be made to the index lines.

burke_wl wrote: ↑Tue Jan 21, 2020 5:34 pm with my Oak/DYN4 setup I had to swap pins 3 and 5, 4 and 6, 9 and 11, 10 and 12 on the communication cable at the oak end. Encoder A+,A- B+,B- to satisfy the requirements in the Oak installation manual on pg.40 (encoder absolute must count positive spinning shaft CCW looking from motor drive end) Both axis cables needed swapped. Not sure if it was really needed, but at the time it was the only way I could find to comply with the Oak setup manual

Did you make your own com cable or did you buy from Centroid?
Are your DB9 and DB25 shells grounded or floating?

I had to swap pins 3 and 5, 4 and 6, 9 and 11, 10 and 12 on the communication cable at the oak end. Encoder A+,A- B+,B- to satisfy the requirements in the Oak installation manual on pg.40 (encoder absolute must count positive spinning shaft CCW looking from motor drive end) Both axis cables needed swapped. Not sure if it was really needed, but at the time it was the only way I could find to comply with the Oak setup manual

That was not really necessary. You could have just set (or not set) Direction Reversal as needed. If the setup manual says that the encoder must count positive when turning a particular direction, then it is being unnecessarily restrictive, probably for the sake of simplicity.

The real rule is this:
- A positive movement command must cause movement that results in positive-going encoder counts.
- A negative movement command must cause movement that results in negative-going encoder counts.

The control does not know or care which direction the motor shaft is turning. All that matters is that the drive and motor respond as stated above.

[/quote]

Did you make your own com cable or did you buy from Centroid?
Are your DB9 and DB25 shells grounded or floating?
[/quote]

I bought the communication cables from DMM. The DB9 and DB25 shells were originally ungrounded. I sent them back to DMM and they reworked the harness.

burke_wl wrote: ↑Fri Jan 24, 2020 10:54 am

Did you make your own com cable or did you buy from Centroid?
Are your DB9 and DB25 shells grounded or floating?
[/quote]

I bought the communication cables from DMM. The DB9 and DB25 shells were originally ungrounded. I sent them back to DMM and they reworked the harness.
[/quote]

So that was before you were having these issues?
I'm not sure what to say or do to help you. I use matched components and DYN4 with Oak in Precision mode.

Marty