AAG Engineering has industrial automation as its core strength. We have rich experience in implementing SCADA in plant operations to gain control and supervise the process or equipment. The SCADA system is the brain of the automation system, so knowing the functionality of SCADA and accordingly choosing the right one for your specific requirements is an important decision.
In today’s article, we will discuss the functionalities of SCADA.
All about SCADA functionality
Access Control
As the name suggests this functionality of SCADA gives access control to the user.Users are allocated to groups, which have defined read/write access privileges to the process parameters in the system. It can also provide access to specific product functionality.
MMI
SCADA functionality supports multiple screens. These screens can contain a combination of synoptic diagrams and text. It also supports the concept of a “generic” graphical object with links to process variables. These objects can be “dragged and dropped” from a library and included into a synoptic diagram.
On-line configuration and customization of the MMI are also possible for users with the appropriate privileges. Links can even be created between display pages to navigate from one view to another.
Trending
The SCADA functionality provides trending facilities. The common capabilities of these functionalities are as follows:
- The parameters to be trended in a specific chart can be predefined or defined online
- A chart may contain more than 8 trended parameters or pens and an unlimited number of charts can be displayed (restricted only by the readability)
- Real-time and historical trending is possible, although generally not in the same chart
- Historical trending is possible for any archived parameter
- Zooming and scrolling functions are also provided
- Parameter values at the cursor position can be displayed.
Alarm Handling
Alarm handling is based on limit and status checking and performed in the data servers. More complicated expressions can be developed by creating derived parameters on which status or limit checking is then performed.
The alarms are logically handled centrally, i.e., the information only exists in one place and all users see the same status, and multiple alarm priority levels are supported.
Alarms can be a group and handled as an entity. Most important of all, it is possible to suppress alarms either individually or as a complete group. The Alarm page facilitates filtering of alarms.
But it is difficult to define relations between alarm in a straightforward manner. E-mails can be generated or predefined actions automatically executed in response to alarm conditions through SCADA.
Logging/Archiving
The terms logging and archiving are often used to describe the same functionality. But both differ.
- Logging is medium-term storage of data on disk whereas archiving is long-term storage of data either on disk or on another permanent storage medium.
- Logging is basically performed on a cyclic basis, that is once a certain file size, time period or a number of points is reached the data is overwritten.
- Logging of data can be performed at a set frequency, or only initiated if the value changes or when a specific predefined event occurs.
When the log is full it can be transferred to an archive. The logged data is time-stamped and can be filtered when viewed by a user.
Report Generation
SCADA functionality supports report generation using SQL type queries to the archive, RTDB or logs. Even Excel charts can be embedded in the report. Functionalities also exist to be able to automatically generate, print and archive reports.
Automation
As mentioned above SCADA is the brain of automation. The majority of the functionalities allow actions to be automatically triggered by events. These actions can be defined by a scripting language. It also supports the concept of recipes. That is a particular system configuration can be saved to a file and then re-loaded at a later date.
SCADA functionality also supports sequencing. Thus it enables to execute a more complex sequence of actions on one or more devices. Sequences may also react to external events.
For further queries, please feel free to get in touch with us at sales-west@aagengg.com or visit our website www.aagengg.com
