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Hello, everyone. I have a problem configuring a servo from StepperOnline: A6-1000EC. My goal is to control this servo via the python api. It should be possible to position it between 0 and 360° as well as rotation with different speeds.

My first attempt was to configure the servo as an angular axis. Then I wrote a simple python program to control the axis via JOG_INCREMENT and JOG_CONTINOUS. For absolute positioning I switch to MDI mode and send my target position. This works totally fine, but I can't run gcode with this solution, because I can't turn the servo continuous in one direction.

So I tried setting up this as a spindle instead. At first I changed my xml so I can process target-velocity and control-mode. Then I used a mux2 to change the control-mode depending on the use of M3/M4/M5 or M19. This works fine and my frequency drive changes between mode8 and mode9. The spindle control with M3/M4/M5 also works fine, but when I enter a command like M19 R180 Q2 P0 the servo drive throws a fault. When the target position is near the actual position this works, so I assume it is some sort of following error. My bigger problem is, that the actual position of the motor after using M3 for some time is very large, cause it is not restricted to one revolution. Is there a way to change that? At my first attempt using it as an axis I used wrapped_rotary, but that only affected the display, not the actual value.

Does anyone know what I could do, or if there is a better way for the use of an servo as position and continuous motion?

Many thanks in advance

langdons wrote:

PCW wrote:

First, is the a 7I92M or 7I92TM?
 
This is old machine, so it's probably an old board, so it's probably a 7i92M (sans "T").

Just for future reference, the age of machine will have no bearing on whether it's a T or sans T. It will depend on the period the card was bought. History will show the the Spartan 6 FPGA was hard to get at one stage, hence the switch to the Trion device.

In real life, despite what the "maker community" will tell you, a capacitor isn't the end all and be all. Also you'll really need to know the load current,ripple and frequency for determining the capacitor reqired, which will differ from application to application, just mentioning this as a PSA.
What is the best option is a quality PSU, yep a bench PSU is great for testing, a genuine Meanwell or Weidmüller (depending on where you are not as easy to get hold of and a little more $$$) supply wont let you down once installed, I only mention these as these are the ones I've been using for eons, all DIN rail mount. I usually switch the computer PSU on, then the MESA boards PSUs, then the stepper power and finally the servo driver for the spindle. To tell the truth with all the relays (self latching) and stuff the PSU wiring was way more complicated than maybe what is should have been. But each circuit controlling the mains is independently controlled.
Regarding powering the 7i77/7i776 or any other DB-25 daughter I've been powering mine(7i76/7i74/7i73/7i83)by the DB-25 connector, found it to be a simple and solid solution. The 7i73 & 7i83 are also powered by the smart serial cable via the 7i74.

Hi everyone,I’ve recently finished mounting my machine to its base and tidying up the wiring, so I decided to try running a quick program to see if everything was working properly.Machine Configuration:

• Controller: Raspberry Pi 5
• Servos: 3 × Leadshine EL8 servo drives with 400 W motors (EtherCAT)
• Spindle: 1 kW StepperOnline drive (EtherCAT)

The program starts fine, but the machine seems to get stuck at the first G1 command.After doing some reading, it looks like this could be related to the “spindle-at-speed” signal in the HAL configuration.Because I’m using EtherCAT, I’m not sure where this needs to be handled:
Should the spindle-at-speed signal be configured in the HAL file, or Is it something that needs to be set up in the .comp file for the EtherCAT drive?

Any guidance or examples on how to handle this signal within an EtherCAT setup would be really appreciated. when the spindle is running currently I am having no feedback from the drive to record the actual speed ? 

2.9.0. I didn't have a 7i92 with me, so I used a 7i96s as the main card, which turned out to be better because I'm planning two additional axes later that will use steppers...now about mpg, maybe and I have an example to try...but I didn't have any experience with connecting potentiometers for feed and spindle override, and any Hal example would be valuable to me.

Yes, that's what I have in the example.

It might work with the cia402pv instead of the standard cia402 also in csp mode.
But I'm not sure, the goal with that component was to add PV, and I may have
broken csp. Not that I meant to, but I didn't check thoroughly.
Also the pv-mode=true and csp-mode=true doesn't work well together,
there should really be a new logic like op-mode=3 (for csp-mode)

Hello Hakan

can i had 2 instances Cia402

Cia402dBraun for xyz and cia402pv for spindle? did you know that?

That worked well. Currently, I'm just testing that the electronics are working; the hardware isn't connected yet, so scaling isn't realistic. What is working is the C-axis and the M commands for spindle movement. The stepper motors are also moving as they should. There are still problems with the M19 command (the servo might be trying to reach a position too quickly, which isn't possible). I'm also checking that the C-axis is working reliably. Currently, there are still problems switching from M3 to S500 for a short time after the C-axis. The servo goes into overload because it seems to be trying to reach a position too quickly, which isn't possible.

Yes there is an example. Two normal stepper drives and one stepper motor spindle.
In the example directory.
 

Hi Hakan
thank you
What should the whole thing look like in the hall and ini? is there an sample?
 

You can use this component instead of the standard cia402 component.
github.com/MetalMusings/cia402pv
The drive uses PV (Profile Velocity) mode which is more suitable
for a spindle motor as it has its own speed ramp up and down.
 

Hallo at all

how can i get an CIA 402 Ethercat stepper work as spindle? I had 3axes (X Y Z) that works. Anybody can help?

Greetings

Okay, so one drive is for a spindle?
I made an adaptation to the cia402 component for the driver to work in PV (Profile velocity) mode
which is better suited to run as spindle.
Check out here github.com/MetalMusings/cia402pv
This person made it work after a while forum.linuxcnc.org/38-general-linuxcnc-q...tor-as-spindle-motor
 

The reference to the forum post was helpful. I now have the basic framework up and running. The servo, which is supposed to act as a spindle, is working to the point that it can be controlled with M commands, and the stepper driver (one driver for two closed-loop steppers) is also working. I've attached the files. More to come.

de.aliexpress.com/item/1005008271228331....gatewayAdapt=glo2deu

de.aliexpress.com/item/1005010098887410....gatewayAdapt=glo2deu

 

Thanks for all info so far.
I decided to change the Y-axis also with a M4-(screw) spindle drive (not M3 as I said before), as I did on the X-axis.
Had the (almost) same stepper-motor around, although after testing it needed 2 times more Volt to be powerful enough.
Now it all looks much better!
The old gear setup was too much worn out, I believe. And 2 (plastic) gears before driving the arm had 1.3 mm backlash is also kinda 'too much'.

PS. I thought I tried the write action at last position in the .hal file (base-thread), but was forgotten to change the .ini file accordingly.
It does run fine now and I am not (willing) able to build back the old situation to test this again, sorry for that.

And yes, I will cleanup my configuration files after this change, the X- and Y-axis are now the same.

Regards, DG.
 

Hello community!
I have a Mesa 7i76e running, the wiring is correct except for the alarm loop. Using a Lenovo ThinkCentre M910q with i7 4-core, 256/GB NVMe SSD, i7 16GB RAM WLAN Intel Core i7-6700T 4x 2.80 - 3.60GHz with Linuxcnc 2.9.4, Probe Basic V.5 on Debian 12. No latency problems.

Once again, I'm here with a big problem. My DIY milling machine (1000x500x220 with aluminum profile frame, 20mm HGR, 1605 ball screws, 3 axes, 2x OMC Stpperonline 400W integrated servo, 1x JMC CL Stepper 3.5Nm, set 2000 steps/rev) is now mechanically finally assembled. I also got a lot of help from this forum in setting up LinuxCNC, eliminating latency problems and spindle control problems, but now I have a milling problem that I can't solve.

I have milled several test parts with drill holes, 2 circular pockets, and a rectangular outer contour, and have noticed that my circular pockets are becoming elliptical. The deviations in Y are approximately +0.35 mm at 45° and approximately -0.38 mm at 135°. The X values for the rectangular contour are perfect to within 0.01 mm in X and 0.09 mm in Y, X I consider to be acceptable, but Y is over tolerance. However, the circular movements contain deviations I cannot tolerate. I will show you a photo of the last test piece. After each individual test part, I made changes to rule out certain things.
The first change was to replace a simple Chinese C7 ball screw with a ground C5 spindle with double nuts. This reduced the originally even higher values by almost half. However, the deviations described above remained. After the next test part, I replaced the 400 W servo with a 3.5 Nm JMC CL stepper motor. The results remained almost the same. As a final attempt, a few days ago I replaced the spindle's fixed bearing with a new one, with 7002AC angular contact bearings in an O-arrangement with a 1 mm spacer ring between the outer rings. I inspected the previous fixed bearing and found no faults. There was a 1mm spacer also and the O arrangement was the same.  I had also taken measurements at the spindle end earlier and actually and found no backlash.

Yesterday, moving away from mechanical faults, I noticed a difference in the motor definitions for the X and Y axes in the .ini file. The Ferror and min_Ferror points differed by one decimal place. X was set to 0.1 and 0.01, while the Y axis was set to 1.0 and 0.1. After I corrected this difference, the motor on the Y axis went into alarm mode after a few position changes.

What could be the reason for this? How can it be that one motor runs perfectly with much lower tolerance values, while the other quickly goes into alarm mode with less load? The motor in question has the same power supply and is certainly less demanding in terms of starting currents than the servo on the X-axis. With the higher tolerance values, the Y motor runs without alarm, but has these deviations. Are these tolerance values in the .ini file responsible for these deviations?
The mechanics of the Y and Z axes are flawless, as checked with a dial gauge, and the repeat accuracy is also very good, less than one hundredth. 
Do you have any ideas about this? Where can I look further?
Thanks for your time and hints