Troubleshooting ASDA-B3 Following Errors (EtherCAT)

Today, I’ve got my setup running with 3× Delta ASDA-B3 servos, a BK1100, and several EL1xxx DI / EL2xxx DO terminals.
I’m using the already implemented DeASDA driver (not CiA402), and the servos run fine.

My homing procedure uses HOME_USE_INDEX = TRUE. Everything works as expected: once the servo hits the index pulse, the homing routine completes and the position resets to zero.

I should mention that I’m fairly new to LinuxCNC, and this is also my first time working with EtherCAT, so I might be missing something obvious in the configuration.

There’s only one thing I still struggle with:
I’m getting a relatively large following error when I jog the servos using the keypad on the drive. Because of that, I had to increase the following-error boundaries significantly. (See INI-File)

At the moment, I don’t have any mechanics attached — the servos are running completely without load. I also auto-tuned the drives, so in theory the gains should be appropriate. What I don’t understand is whether this behaviour is caused by the EtherCAT cycle time (2 kHz) or by suboptimal tuning parameters (gains, filters, etc.) inside the servo drive despite the auto-tuning.

Does the following-error configuration need to be set differently when using EtherCAT communication compared to pulse/analog control?

I’m also not sure which exact HAL pins I need to connect to the Probe_Basic UI to make everything safe and fully functional. Any guidance on the required pins, signals, and safety interlocks would be extremely helpful for someone who’s still new to LinuxCNC.
I’d also love to see some example HAL/INI configurations of fully set up 3-axis machines, ideally with a carousel-type tool changer and a 3D probe — that’s what I want to configure next 

Your servos need manual tuning.
10 mm, one mm, or even one tenth of a mm is too much following error.
Standard servo tuning techniques applies.
Maybe don't spend too much on it now, you need to redo it in the machine with its inertia.
 

Thanks ... that confirms what I suspected. I really hope the auto-tuning on the Delta B3 drives works better once they have the proper inertia of the machine. Running them completely without load probably doesn’t give the controller anything meaningful to work with.

I’ll revisit the tuning once everything is mounted mechanically. Fingers crossed that the B3’s auto-tune behaves more reasonably under real conditions.