Servo Wiring and Tuning detailed How To example Mesa 7i77.

I would disable feedback (you can do this on a per joint basis by setting P, I, and D to 0)
and then set the output voltage by setting the PID bias parameter. (you can set this live with
the calibrate menus "Test" button)

This should allow you to:

1. Check the 7I77 output voltages (7I77 unconnected to drive)
2. Check the drive behaviour when set voltage are applied from the 7I77 (7I77 connected)

The maximum  voltage I can get out of the 7i77 is 0.096v (disconected) and 0.078 connected, it doesn`t matter what value is in the bias field there is no change in output voltage from the 7i77 when you press the test button.
Assuming linuxcnc is ok then to me its pointing to the 7i77. what do you think ??

I would check

hm2_5i25.0.7i77.0.1.analogena
and
hm2_5i25.0.7i77.0.1.analogout0
with halshow

if analogena is true, analogout0 is +10 you have no real-time warnings
(and OUTPUT_SCALE is 10) and you don't get close to 10V on the 7I77
analog output 0 (7I77 TB5 pin 4 relative to TB5 pin 3) Then there is likely a
problem with the 7I77

Hi I did the test with no result and after purchasing another 7i77 this cured the problem, now I`ve just got to learn servo tuning ??

gnipsel.com/linuxcnc-old/tuning/index.html

Changed the title to reflect wiring since a lot of detail is about wiring and testing practices.

Great! Was wondering where this went!

Now, can someone edit this older post to reflect the new url: forum.linuxcnc.org/10-advanced-configura...7i77?start=80#143677

(404)

gnipsel.com/linuxcnc-old/tuning/index.html

Amazing how-to, thanks, great starting point for me.

I find this video with a basic overview of the tuning method to provide quite supplementary information

Ziegler-Nichols Method

In halscope what are the units ?
For example if set f-error to 200m/div what and i see 1 div how this translates to mm ?
Also in cmd-velocity if i set to 1/div how this translates to mm/sec ?

I have seen a post by @andypugh that showed an alternative method of pid tuning
know anyone the link of this post ?