Thanks Bob, that is interesting. I tried looking at the encoder signal with my oscilloscope,?which I do not know how to use, and the signal looked really messy, not clear steps as expected.
re: Grounding the motor is that Earth ground or Com, possible that might explain the problem I am having.
The encoder is on the wire side of the motor, would it help to move to the other side?
Ralph
On Sat, Mar 21, 2020 at 11:36 PM Bob T <
zs6bxi@...> wrote:
Yes that would work Ralph !?
Of course you then might have to worry about getting the grounding of the motor really sorted to stop coupling of the drive power signals into the encoder. I¡¯ve spend most of my 45 years or so working life doing drives and feedback systems ( most of them very large in size 1 ~ 10 MW). And I¡¯m always surprised how Murphy manages to get in the way. The latest digital drives are no exception.....when someone gets the order of the running of the subroutines wrong the drive still works but the response is just horrible.?
Regards Bob
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Thanks for the replies, and everyone is welcome to jump in. Bob my encoder is mounted directly on my motor.?
<IMG_20200321_102907196.jpg>
Ralph
On Fri, Mar 20, 2020 at 10:24 PM Bob T <
zs6bxi@...> wrote:
Hi Ralph,
excuse me but I have been ¡°lurking¡± on this thread and wanted to add to the discussion.
It¡¯s quite possible that a chunk of your jitter problems are coming from your method of driving the encoder ! Any time that one can see the belt ¡°flapping¡± or moving around its a good sign that the encoder is speeding up and slowing down during each revolution. Normal V belts are very bad at this. The poly V belts are much better. The toothed belt drives CAN be very good. Direct connection with the spindle of the encoder clamped into an inline hole on the drive/chuck is the best. But with the body of the encoder stopped from spinning only by a torque arm connection. The torque arm should be of two parts. One connected to the encoder and the other via a rose joint or similar to the steel work. The two should be at 90 degrees to each other. The longer they are, the less wobble in the encoder feedback will be seen.
Regards Bob
?
I have not found any that just work! At best, if they show RPM they do not show the same rpm with a steady running motor. A few do not show anything.?
I do not "think" I need to be concerned with rotation, especially with my lathe, the chuck might unscrew if I tried to do any work in reverse.
My desk?time and shop time is just about over, yesterday I was already doing Honeydos in the garden. I had thought I could make it to April 1 but the garden is calling, and I like to eat it's produce.
I also am having problems with dependable repeatable stepper motor code.
Of course I am not a programmer.
Ralph
On Fri, Mar 20, 2020 at 12:11 PM CLevinski <
clevinski@...> wrote:
Ralph,
Ah, I couldn't see that before. It looked like it was direct mounted. Good job!
No, I don't have a program that will read the encoder, but it should be fairly simple. Are you concerned about direction of rotation? What problems have you encountered with trying to read the encoder to date?
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Regards,
Charlie
New Jersey, USA
LAW OF ANNOYANCE: When working on a project, if you put away a tool that you¡¯re certain you¡¯re finished with, you will need it instantly.
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Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
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Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
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Clausing 8520, Craftsman 12x36 Lathe, 4x12 mini lathe, 14" Delta drill press, 40 watt laser, Consew brushless DC motors and a non working 3D printer
