Universal Robots+

C4A89 Communication Issue: Packet Counter disagreement in package from joint


the company that I work for has different applications/programms for different sized UR Robots.
In the log file we found the error/warning in the title.

We got that error on different machines and with different programs.
Most of the times the lost packages are from the smaller joints (with higher number like 3,4,5).

What could be the reason for the problems and what can we do to fix the problems ?

Best Regards,
Alexander Apostolidis

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Did you solve it?? My robot is doing something similar but with code C4A91 joint 5 and can’t boot

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These sound like errors that may be specific to your robot/application. C4A89 deals with packet count disagreement when trying to communicate to a joint. There could be an issue with the communication cables to the joint. Or if it is happening on different units it may be an electrical issue.

C4A91 is a similar error, but dealing with a different joint.

You can read more on these codes in the service manual: https://www.universal-robots.com/download/?option=41381#section41378

I’d recommend you contact your local distributor for help troubleshooting the cause and hep resolving the issue as well.