Kind of. Only commands get transmitted over Modbus. Commands are usually triggered by UI actions or generated by rules. Commands are a transient event.
There is no built-in ability to decide that some external device doesn’t match what openHAB thought it was, and transmit a command to correct it.
But of course you can use rules to create your own version of something like that.
A requirement to do that would be the ability to read back the external device’s state. I can see some problems for you here -
That message only comes from autoupdate (in response to a command).
You don’t generally want autoupdate with read-polled Modbus Items, and you have tried to select autoupdate=“false” so I really wouldn’t expect to see that.
The problem here is that you have a typo
Switch mb_con_bit_3 "mb_con_bit_3" {channel="modbus:data:wago:wagooutputscon:mb_con_bit_3:switch", autopudate="false"}
autoupdate= not autopudate=
Once that’s sorted, your next issue is that you have defined data Things mb_con_bit_0 and friends as write only.
You don’t seem to have any means to read the PLC…
Is this what the mb_stat_output0 data Things are about? If so, you can combine your read and write into one data Thing.
The read part of a data Thing must correspond with the poller Thing it belongs to, of course.
But the write part can be some other register address altogether, even a different type (this is why they are specified separately).
Get your Items reading properly and we’ll think about your error recovery. This might help with ideas (detecting device coming online after failure)