Third party OPC communication
I am trying to establish a communication with Yokogawa DCS. Inorder to achieve the same this is the procedure i followed:
> Created generic OPC Server network on control structure.
> Created Service for the same.
> Performed DCOM settings on both machines i.e. connectivity server on 800xA side and server on yokagawa side.
After performing the DCOM settings, i see that i am able to read the data on 'ADVDSOPCCLIENT' and 'Matrikon OPC Explorer' however the service i created on 800xA is not going to service state.
With respect to the opcda service there two types of behaviour i am observing.
> When i run the service on the node on which i made the DCOM settings the service keeps switching between "undefined" state and "initialize" state such that it is in undefined state for 1 minute and initialize state for 2-3 seconds and this keeps repeating. In this state i am neither able to append the data nor am i able to retrieve the data.
> When i run this service on any other node on which i have not done the DCOM settings the service goes to "initialize" state. Here I am not able to retreive the data . The retrieve fails with the following error message "Error:Failed to change browse position!" "Error: Failed to browse the OPC server: The parameter is incorrect.".
However when i try to append the data, the objects are appended successfully. But still there is no change in service state it remains at initialize and when i subscribe live data i get bad communication error.
Some points to note:
I am receiving data from the yokogawa DCS. There is no data being transferred from 800xA to yokogawa DCS.
800xA version:800xA 5.1 FP4 RevD
The Matrikon and ABB clients mentioned run as desktop (foreground) users while the OPC DA Connector run in the background as a service.
Some servers display a GUI, which will not work for a client running as a background service.
An OPC tunneler might resolve problems with DCOM and firewalls.