The world has changed dramatically since then and control is now very distributed. While we still use the word SCADA to refer to an overall system such as regional water or electricity distribution control system the term is more directly applied these days to the 'SCADA' software application which is typically PC based and sits on top of the distributed control system.
The SCADA software in this scenario does not do any control but rather provides an interface for the user to see the status of the distributed control system and send command requests to the remote controllers such as turn on a remote water pump. The SCADA application also provides functionality such as alarm notification, data logging and event logging. Being PC based the system is capable of keeping large amounts of historical data for recall and analysis.
When once looks at the functionality of a more SCADA and compares it with a dedicated HMI touch screen it appears that there is a lot of overlap and the fact is that with the development of both classes of product there is a blurring of the lines particularly at the low end. However PC based SCADA still distinguishes itself from its smaller cousin in its ability to scale for large distributed multi-screen systems.
The use of the Windows based operating system for SCADA means integration and standards adoption not available on a dedicated HMI.
Features of our Scada Systems are:
- Configurable in single station, client-server, terminal-server or web-server/client arrangements
- Configurable in redundant failover configurations
- In-built functionality such as time schedulers and recipe managers
- Directly access applications such as email for alarm notification
- Is a container for running ActiveX and Java Beans
- Can use ODBC for integrating with database
- Can use SQL Server natively for data and event logging
- Ues VBA for scripting
- Uses OPC (Windows OLE for process control)
For information about our SCADA Systems solutions, please visit our Scada Products page.