Centroid Community CNC Support Forum

Just received this from Geckodrive:

John,



At this point I am not sure what the problem could be; the drives are identical and this appears to be an application-specific issue. This sounds like there is an out-of-spec signal being sent to them and the higher resolutions are more sensitive to this as the pulse width narrows. However, without an oscilloscope it will be near impossible to track down. The drives have been replaced with new ones and the old ones were tested at 256 microstep without issue.



If you like we can refund the drives; just mail them back here and once we test them to verify they are not damaged we can issue a refund. I have CC’d Jess if you would like to go this route so she is aware.



Please let me know if you have any questions. Thank you!



Marcus Freimanis



Geckodrive, Inc.

1540 S Grand Ave

Santa Ana, CA 92705

John,
You have 8 wire steppers. It makes a difference as to how the motors are connected to the drive. Both inductance and current. (You have not said how they are connected to the drive) The only motor that gives any decent information is the Stepper Online motor. I would personally chuck the other two. They do not provide inductance and current ratings based on how they are wired to the drive.

Screen shots of the specs of each motor:
34HS38-3008S 86AM120: 86J8156-845: Please tell us how you have the motors connected to the drives
Please tell us how you have the drives connected to Acorn, (Header or DB25) Keith asked you to follow a schematic that uses the +5VDC from Acorn power supply to the COM of the G214 and take the drive step/dir signals to the DB25. IS that how you wired it? If so, did you try and go in the advanced tab and try and invert the step and direction signals to see if that improved things?)
Please post a picture of your control cabinet showing Acorn and the drives.
Please tell us if you are in the US? Maybe we can help you source better motors.
Please tell us about the machine. I had asked you to follow this post: viewtopic.php?f=60&t=1043
That would give us a bigger picture of what you are working with.

Marty

The step and direction are connected to the db25. The com to Acorn 5V. I tried reversing the step and direction wires. No difference. The machine is all steel construction. I am located in Ontario Canada.

While we figure this all out...would the the Clearpath CPM-SDSK-3432S-RLN drive be an appropriate choice or could I go with something smaller? I thought I would get a system quote for the future (mid next year). Thanks

tuffduck wrote: ↑Thu Nov 18, 2021 10:49 am While we figure this all out...would the the Clearpath CPM-SDSK-3432S-RLN drive be an appropriate choice or could I go with something smaller? I thought I would get a system quote for the future (mid next year). Thanks

That's a conversation to have with Teknic Application Engineers. The will need to know
Ballscrews pitch
Desired machine speed
Size of existing motors or the frame size/torque specs of the motors that came on the machine.

You don't reverse the step and direction wires.
In the Wizard Advanced Tab, you INVERT the signals by clicking the box next to step and direction.

You really need to replace the inexpensive Chinese steppers with little information on them olin my opinion. You have no idea what the current/inductance values are based on how the 8 wire steppers are connected to the drive.

You still have not provided how you wired those motors to the drive, and even if you did, I am not clear based on the specs provided what the inductance and current is.

Try automationtechnologiesinc.com for better steppers.
Or, change to Clearpath SDSK if that's the route you eventually intend to go.

Just my opinions...
Marty

Cant just change to servos currently, so without the machine no money generate to buy them.

The 1800 oz stepper motors at automationtechnologies exceed the rated amperage for the Geckodrives. They still don't have anything in the 1400oz range after 18 months of checking there.

The 86AM120 only has 4 wires. inductance of 8Mh

The 86J18156-845K has an inductance 5.2Mh

tuffduck wrote: ↑Thu Nov 18, 2021 12:24 pm Cant just change to servos currently, so without the machine no money generate to buy them.

The 1800 oz stepper motors at automationtechnologies exceed the rated amperage for the Geckodrives. They still don't have anything in the 1400oz range after 18 months of checking there.

The 86AM120 only has 4 wires. inductance of 8Mh

The 86J18156-845K has an inductance 5.2Mh

At what current rating? It is substantially less wired in parallel than series. This needs to be known and set properly in the drives.

I'd your motors were working with old stepper drives, what necessitated the upgrade to Geckodrive G214's?

I have requested a new G214 for testing with Acorn. If I get one, I will test and do a video