I occasionally get an alarm from Yaskawa Sigma-7 (and perhaps Sigma-V) drives. It often happens after I’ve been running a while, and then make a configuration change or restart the network, or recreate all the RSI objects (due to a configuration change/reset).
The Yaskawa manual says this about this alarm:
The EtherCAT communications state left the Operational state during motor operation.
Can you provide any more details what might cause a problem described in this way or at least what this error might signify?
Usually when I get it, I just power cycle the drives and move on. (It doesn’t usually happen again for a while.) I’ve recently gotten a report of it happening for a customer, which means it’s probably time for me to investigate further.
The Yaskawa is strongly objecting to the amp being enabled and potentially moving when the network dropped. This might be caused by a excessive jitter, a cable break, or an interruption of the process/node without respect to the state the Yaskawa is in. Any time you start a recovery/shutdown process, I’d use the Axis::Abort() function at least Axis::AmpEnableSet(false) before moving on. Not all nodes will care, but Yaskawa decided to add their own safety loops for situations like this. A shame it isn’t more easily cleared though.