Architecture

Sapphire Trend is a Client/Server based application.  Data Collection is performed by the Sapphire Collector (the Server) with data presentation and management being performed by stPro, stOCX or the stManager (the Clients).

Sapphire Trend can be operated by a single user working on an individual PC, or by a group of users on a network sharing a common Sapphire Collector (Server).  In addition the user can elect to bypass the collector and connect directly to an OPC Server.

1.  Single User

In Single-User mode, the Sapphire Client and the Sapphire Collector both execute on the users machine.  The user is responsible for defining items for the Sapphire Collector to fetch via the stManager.

Tip:  This mode of operation is also intended for low volume analysis where an individual user wants to accumulate data over a period of time for their own personal use.

2.  Multi User

Tips :  When operated in Multi-User mode, the Sapphire Collector should be run on a centrally managed node offering continuous availability.

3.  Direct DA and HDA Connectivity (Ad-hoc)

Users not wishing to use the collector can connect the Sapphire Clients directly to either DA or HDA OPC Servers.  This can be especially useful when a plant-wide historian is already in use since it avoids scanning the items again from the underlying process.

Tip :  Connecting directly to either DA or HDA OPCServers allows SapphireTrend to be used as an Ad-Hoc trending tool since data that has already been scanned can be displayed and no additional item configuration is required.  

Note:  HDA (Historical Data Access) offers an advantage over DA (Data Access) as historical information can be fetched to show data collected before the trending client was started.  This is not possible with DA where only live data can be displayed.

Note:  The examples shown above have been kept simple to aid clarity.  In reality, users can combine all three modes of operation.  For example, if the appropriate configuration is performed a user running a local Collector will also be able to connect to their own Collector, or any centrally managed Collectors that exist or directly to any available OPC Servers.

When choosing which mode to use, the following issue should be considered:

Tip:  Where the load on the underlying control system needs to be carefully managed, then a Multi-User environment is preferable since it reduces the number of times data items are scanned.