800xA integration with PI using AfwOpcDaSurrogate
1. We are planning to include the primary PI OPC DA Interface client node to our 800xA domain and connect it via DCOM to the AfwOpcDaSurrogate OPC server on the primary Aspect server A, and the backup PI node - to the secondary Aspect server B. We have multiple redundant connectivity servers, so accessing AfwOpcDaSurrogate on the Aspect servers seems easier rather than connecting to individual connectivity servers.
2. Another option is to connect PI OPC clients to AfwOpcDaSurrogate servers running on individual connectivity servers.
3. The third option is to install AfwOpcDaSurrogate on the PI interface nodes and access them locally. Which installation package the AfwOpcDaSurrogate OPC server comes with?
What do you think will be the best option?
Aspect server(s) should be fine.
The surrogate has no track record of bloating CPU or memory (advocating a move off the aspect servers).
Study best practice! Eg there is a BIG difference between a scanning and a subscribing OPC client. Some connectivities like MOD300 or 800xA for Advant Master have significant bottlenecks in OPC that need special care. Proceed with caution.
Buy license for third party OPC client(s)
NO NO NO NO NO!!!
Do not use OPC-DA as the interface between 800xA and PI. This places significant extra subscription load on to the controllers and is entirely the wrong interface to choose. As Stefan says, mis configuration of the DA interface can cause serious issues with Advant master CPU loads and even flat out crash MOD300 systems.
The correct interface to use is OPC-*H*DA. The *HISTORY* OPC Interface
You are already logging a large number of points onto the 800xA Basic History service. By using PI's OPC-HDA interface, you subscribe data from the Basic History serverice, NOT the controller. Your PI data collection piggy backs on the existing history and adds no extra load onto the controllers.
You also automatically get redundancy doing this. The PI Interface can recover history data after a failure. As long as basic history has the data then the PI interface can recover that data, even if the interface has failed for days or weeks.You can also backfill data if you are adding PI to an existing 800xA system.
The opc interface you are currently suggesting cannot do this and requires a redundant installation or you *WILL* lose data at some point.
The suggested installation for the PI OPC-HDA interface is to use a seprate "interface Node". This is simply an 800xA client. Install the PI interface software on this node, configure buffering etc and connect the PI interface to the OPC History data source running on the local machine. 800xA then handles all of the redundancy between the 800xA history service providers. The PI interface will be able to access any point that has an 800xA log configuration.
To configure the PI points, Extract the 800xA History Log configuration using the BDM log manager spreadsheet and filter out the required logs. The Pi Point Data source is simply "ObjectName:Property"