Welcome to the forum............
Please stop editing your original post.
As you're new, your original post requires moderation before being displayed on the forum.
(I have approved this 4 times already).
Each time you edit it, it will be removed from the board for moderation purposes and therefore will delay your post from appearing to members.....
Oh sorry for that. I tried to be as clear as I can and English is not my mother tongue. Thank you for your work and for the welcome!
Quote from the provided manual:
'GND: To be used to have a common ground between the robot and the gripper/sensor'
You have to connect the ground to the one and only pin that's labeled with GND.
Which is the GND output of the KUKA controller?