Comments on: Solving drive overvoltage/undervoltage faults

By: Tero

Tero — Sun, 09 Aug 2015 09:40:07 +0000

To overcome this, you need to reduce DIV parameter value which sets the scale of velocity/acceleration limits. I.e. if you change DIV from 100 to 10, you will get 10 times more range in velocity limit. Also change MUL if you wish to keep the setpoint scaling.

I’ll put a note about this somewhere in the wiki :)

By: Tero

Tero — Sun, 09 Aug 2015 09:38:39 +0000

That’s good point! In the next version TSP will have 10x range.

By: Tero

Tero — Sun, 09 Aug 2015 09:36:48 +0000

This happens because hard stop home point happens on or little bit beyond the end of travel, so when home point is set there, drive will try to drive axis towards the end of travel. The correct solution for this is to set homing offset parameter so that it moves away from the hard stop.

Indeed this is bit unintuitive behavior and I have put it on the TODO list to change it.

BTW, sorry for long delay on answer! I was not following this for a while due to travel etc. Your feedback is very welcome and I appreciate!

By: jan beck

jan beck — Tue, 28 Jul 2015 04:43:43 +0000

I can also confirm that IONI works on a Parker MX80L linear motor with sin/cos feedback.
However, in this case, the issue of the field sizes in Granity is a real problem. Aside from the stimulus issue I already reported, several other things just won’t work well.
The velocity field limits me to 32767. So even with the SinCos setting at only 64X, the max velocity is 128 mm/s. The motor is rated up to 2000mm/s….

I suspect similar issues with other fields as well.

Am I doing something wrong?

By: jan beck

jan beck — Fri, 24 Jul 2015 07:03:24 +0000

And if you are not sick of me just yet, I have one more thing to report:
in the testing tab of Granity, the TSP fields are limited to 99999. I have a linear motor with 1/2 micron glass scale here, so that limits me to <50 mm moving. Would be nice if that field could be increased in size, because I do have some other linear actuators here with 50 nm resolution….:P

By: jan beck

jan beck — Fri, 24 Jul 2015 07:00:22 +0000

I have another potential bug report. I have tested this on two separate linear motors of different manufacture. When I go and do the hard homing and set the HMF movement to 0, so that the motor stops at the homing position, it goes crazy and starts pulling over 1A of current trying to hold it there. If I simulate a hard stop with my finger or set a move away from the hard stop (even a few microns), then there is no problem.

By: jan beck

jan beck — Fri, 24 Jul 2015 06:56:53 +0000

Ah, I see that cute RECOM switcher. I have a question:
I have been running my experiments with a bench power supply at 24V going to both HV and logic. If my final machine is at 24V, is that a good practice, or should I put a separate 24V SMPS to supply the logic voltage?

By: Tero

Tero — Thu, 23 Jul 2015 12:28:27 +0000

Indeed, it’s fixed now. Thanks!

Yes, there is on-board 24V to 5V regulator for encoder and IONI.

By: Tero

Tero — Thu, 23 Jul 2015 12:27:24 +0000

Thanks for pointing out! That error was also in other pages (fixed earlier), but that table was missed. It’s fixed now :)

By: jan

jan — Thu, 23 Jul 2015 02:20:17 +0000

I think I found another typo.
On this page:
http://granitedevices.com/wiki/IONICUBE_1X_electrical_specifications
the typical input requirement exceeds the maximum.

Related to that, it is not clear to me what happens to the 24V supply. Some is clearly regulated to 5V for encoder and such right on the IONICUBE 1X. How is the 24V logic turned to something that IONI can use? Regulator on the IONI board?