Cannot write property value to Kepware in the remote thing

[seanccc]

Hi,

I got a very strange phenomenon.  I have a remote thing which is bound to the data tag of Kepware, when kepware detect the change of PLC,  the data change event of the property in Thingworx will trigger the subscription to update the same property, but it doesn't take effect , the property in Thingworx still remain unchanged ,  and there is no error found.  But if manually change the data tag in Kepware or using timer then it works.  

In a summery : 

• PLC -> update Kepware data tag -> raise data change event in Thingworx -> trigger subscription -> execute sync service to update the property value  ==>  does NOT work . no effect  
• manually update Kepware data tag -> raise data change event in Thingworx -> trigger subscription -> execute sync service to update the property value  ==>  works 
•  PLC -> update Kepware data tag -> launch a timer to poll the property value -> execute the same sync service to update the property value    ==> works 
•  PLC -> update Kepware data tag -> launch a timer to poll the property value -> raise data change event in the timer-> trigger subscription -> execute sync service to update the property value    ==> works 

Any idea about it ?  

Thingworx: 8.5.4

Kepware:  KEPServerEX 6.8

PLC: SIEMENS 1200

Regards,

Sean

[Constantine]

Hello @seanccc,

The only thing I can think of is comparing the users -- for that add some debug logs to your subscriptions and compare the resulting log records.

Probably if you share the code of this part "trigger subscription -> execute sync service to update the property value", then it would be possible to find the issue, why it takes no effect...

/ Constantine

[slangley]

Hi @seanccc.

Have you found a solution to your problem?  If so, could you share the solution with the community for others that may be experiencing the same issue?

Regards.

--Sharon

[seanccc]

@slangley ,

Not yet,  we're currently use a timer to poll and update as a workaround. 

Regards,

Sean

[slangley]

Hi @seanccc.

We're not understanding this scenario:

• PLC -> update Kepware data tag -> raise data change event in Thingworx -> trigger subscription -> execute sync service to update the property value  ==>  does NOT work . no effect  

When the Kepware data tag is updated, the thing property in ThingWorx should also be getting updated.  So when the subscription is triggered, it seems that the value could be getting overwritten, if another update comes in before the subscription completes.

Are we misunderstanding something?

Regards.

--Sharon