Every SCADA server loads a process database at start-up. Once loaded, the database:
- Receives values from an I/O driver or OLE for Process Control (OPC) server.
- Manipulates values according to its configuration (a control strategy).
- Compares the values to alarm limits you define.
- Outputs adjusted values to the I/O driver or OPC server.
- Sends alarms to operator displays, printers, files, and network alarm destinations.
The following figure illustrates how values enter a database, travel through a sequence of blocks, and exit the database as output.
