Centum CS do not have OPC client facility & hence OPC server of Delta V may not communicate. Centum CS database has to be control processor level & not at console level.
TCP/IP XL NET is at consol level & normally for database equalisation & dumping the data to third party & not for import.
To solve your problem, DeltaV have Modbus Card which would work as Master or SLAVE, hence data can be transfered DELTA v databse on Modbus RTU. cENTUM cs have modbus master protocol & communicate.
If you want data transfer independent of Console the only way to use Modbus.
Thanks to everyone for the input. I had already thought about some of the suggestions passed. The two systems are located very far apart, so cabling cost for Modbus rules it out. There is an existing TCP/IP LAN infrastructure linking up the locations. On the DeltaV side there is an Application Station with OPC server, and a layer-3 network switch linking up to the LAN.
But the old Centum CS on the other side runs on UNIX system which does not support OPC. I need to get around this problem and have the DeltaV tags available to the operators on the Centum (only one-way communication for monitoring, no control is done).
What is required on the centum side to achieve this? (Remember I only need Centum CS to be client)
Modbus will require new RS232 new cabling, and the route between the two systems is far apart and has many obstacles in between. I am trying to see if I can exploit the existing TCP/IP LAN infrastructure. The application is not very critical. I know in terms of OPC I will hit jackpot on cabling and additional hardware costs, but I need to know if anything can be done on the centum operator station to see OPC tags (even thought operating on UNIX).