UR20 Joint Replacement?

Technical Questions
1

We just got a second hand UR20 and Wrist 1 started acting up today while programming. The robot moves very “jerky” and eventually alarms out. I can provide videos. All other joints move fine. We we get the code “Wrist 1A: C273a9: Cross Monitoring: Disagreement on velocity”

We have tried rebooting the robot and nothing seems to make it work. If I turn the speed down to 10% or so it will work for a bit but as soon as you turn the speed up it alarms out almost immediately.

I also do not have access to the admin or safety passwords. I am trying to obtain that but do not have high hopes. Do I need access to those passwords to replace a joint?

2

I would definitely submit a case to MyUR, but I don’t think you need either password to replace a joint.

As for needing the passwords, see here: Reseting passwords - #8 by terryc for resetting the admin password if it’s lost, and here: In case of lost password - #2 by eric.feldmann for resetting the safety password.

3

Do you have experience with UR robots? To me it sounds like something simple as a wrong payload being active.

Also, which software is installed? You could reset the whole system with a new image, which will also remove the passwords.

Otherwise, I agree with Eric. You should make a case on MyUR and submit a support file with it.