Hi everyone,
Today, my TMC AC servo motors arrived, and I started setting them up.
I configured them to run at **4000 steps per revolution**, which was straightforward.
I'm aiming for a **G0 speed of 8000 mm/min**, but unfortunately, **Centroit Acron only allows me to set 1200 mm/min**.
Here are the details of my setup:
- **Ballscrew pitch**: 5 mm/rev
- **Steps per revolution**: 4000
- **Controller setting**: 400,000 steps/sec
Based on my calculations:
- 1200 mm/min = **20 mm/sec**
- 20 mm/sec / **5 mm per rev** = **4 rev/sec**
- **4 * 4000 steps = 16,000 steps/sec**
This is far below the 400,000 steps/sec limit, so I don't understand why I can't set a higher speed.
Does anyone have an idea what I might be doing wrong?
Thanks in advance!
Issue with TMC AC Servo Motors and Centroit Acron - Speed Limitation? <resolved >
Moderator: cnckeith
-
- Posts: 8
- Joined: Thu Mar 13, 2025 10:29 am
- Acorn CNC Controller: Yes
- Plasma CNC Controller: No
- AcornSix CNC Controller: No
- Allin1DC CNC Controller: No
- Hickory CNC Controller: No
- Oak CNC controller: No
- CNC Control System Serial Number: B83DF60BBF62-0128259041
- DC3IOB: No
- CNC12: Yes
- CNC11: No
- CPU10 or CPU7: No
Issue with TMC AC Servo Motors and Centroit Acron - Speed Limitation? <resolved >
(Note: Liking will "up vote" a post in the search results helping others find good information faster)
-
- Tech Support
- Posts: 72
- Joined: Wed Jan 29, 2025 9:39 am
- Acorn CNC Controller: No
- Plasma CNC Controller: No
- AcornSix CNC Controller: No
- Allin1DC CNC Controller: No
- Hickory CNC Controller: No
- Oak CNC controller: No
- CNC Control System Serial Number: none
- DC3IOB: No
- CNC12: Yes
- CNC11: No
- CPU10 or CPU7: No
Re: Issue with TMC AC Servo Motors and Centroit Acron - Speed Limitation?
Hello there,
To help us get a little more info on your system please post a fresh report.zip and any schematics or manuals you're using.
To help us get a little more info on your system please post a fresh report.zip and any schematics or manuals you're using.
Want to post your own question?
Check this out first: http://centroidcncforum.com/viewtopic.php?f=60&t=1043
Acorn CNC tech tips: viewforum.php?f=63
Check this out first: http://centroidcncforum.com/viewtopic.php?f=60&t=1043
Acorn CNC tech tips: viewforum.php?f=63
(Note: Liking will "up vote" a post in the search results helping others find good information faster)
-
- Posts: 8
- Joined: Thu Mar 13, 2025 10:29 am
- Acorn CNC Controller: Yes
- Plasma CNC Controller: No
- AcornSix CNC Controller: No
- Allin1DC CNC Controller: No
- Hickory CNC Controller: No
- Oak CNC controller: No
- CNC Control System Serial Number: B83DF60BBF62-0128259041
- DC3IOB: No
- CNC12: Yes
- CNC11: No
- CPU10 or CPU7: No
Re: Issue with TMC AC Servo Motors and Centroit Acron - Speed Limitation?
I think the settings regarding steps/revs and the overall turn ratio are fine. When I move the axis by 5mm, the drive completes one full revolution.
- Attachments
-
- report_B83DF60BBF62-0128259041_2025-03-13_16-07-13.zip
- (1.02 MiB) Downloaded 1 time
(Note: Liking will "up vote" a post in the search results helping others find good information faster)
-
- Tech Support
- Posts: 72
- Joined: Wed Jan 29, 2025 9:39 am
- Acorn CNC Controller: No
- Plasma CNC Controller: No
- AcornSix CNC Controller: No
- Allin1DC CNC Controller: No
- Hickory CNC Controller: No
- Oak CNC controller: No
- CNC Control System Serial Number: none
- DC3IOB: No
- CNC12: Yes
- CNC11: No
- CPU10 or CPU7: No
Re: Issue with TMC AC Servo Motors and Centroit Acron - Speed Limitation?
Would you be able to try this on our newest version of CNC12? v5.30
In 5.26 there was a bug where for metric systems the axis max rate was being calculated for imperial units:
viewtopic.php?f=60&t=11141&p=97639&hili ... .26#p97639
In 5.26 there was a bug where for metric systems the axis max rate was being calculated for imperial units:
viewtopic.php?f=60&t=11141&p=97639&hili ... .26#p97639
Want to post your own question?
Check this out first: http://centroidcncforum.com/viewtopic.php?f=60&t=1043
Acorn CNC tech tips: viewforum.php?f=63
Check this out first: http://centroidcncforum.com/viewtopic.php?f=60&t=1043
Acorn CNC tech tips: viewforum.php?f=63
(Note: Liking will "up vote" a post in the search results helping others find good information faster)
-
- Community Expert
- Posts: 3406
- Joined: Thu Sep 23, 2021 3:49 pm
- Acorn CNC Controller: Yes
- Allin1DC CNC Controller: No
- Oak CNC controller: No
- CNC Control System Serial Number: 6433DB0446C1-08115074
- DC3IOB: No
- CNC12: Yes
- CNC11: No
- CPU10 or CPU7: No
- Location: Germany
Re: Issue with TMC AC Servo Motors and Centroit Acron - Speed Limitation?
Yes this is solved in 5.30
I recommend anyway to start with the latest version software.
Uwe
I recommend anyway to start with the latest version software.
Uwe
(Note: Liking will "up vote" a post in the search results helping others find good information faster)
-
- Site Admin
- Posts: 8803
- Joined: Wed Mar 03, 2010 4:23 pm
- Acorn CNC Controller: Yes
- Allin1DC CNC Controller: Yes
- Oak CNC controller: Yes
- CNC Control System Serial Number: none
- DC3IOB: Yes
- CNC11: Yes
- CPU10 or CPU7: Yes
- Contact:
Re: Issue with TMC AC Servo Motors and Centroit Acron - Speed Limitation? <resolved >
Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
(Note: Liking will "up vote" a post in the search results helping others find good information faster)
-
- Posts: 8
- Joined: Thu Mar 13, 2025 10:29 am
- Acorn CNC Controller: Yes
- Plasma CNC Controller: No
- AcornSix CNC Controller: No
- Allin1DC CNC Controller: No
- Hickory CNC Controller: No
- Oak CNC controller: No
- CNC Control System Serial Number: B83DF60BBF62-0128259041
- DC3IOB: No
- CNC12: Yes
- CNC11: No
- CPU10 or CPU7: No
Re: Issue with TMC AC Servo Motors and Centroit Acron - Speed Limitation? <resolved >
quick update – the issue was actually caused by the software version!
now everything is working perfectly.
Thanks a lot for your help !
now everything is working perfectly.
Thanks a lot for your help !

(Note: Liking will "up vote" a post in the search results helping others find good information faster)