This object allows you to collect a great amount of information via OPC servers, Elipse drivers, databases in general, or even with text files, and to store it in commercial databases (Microsoft SQL Server and Oracle) via user-defined historic objects, in a compact, efficient way.
Storage and Compaction
E3Storage stores any type of information (analog, digital, or text values) via Relational Databases such as Microsoft SQL Server and Oracle. Its special algorithm allows for up to 95% of compaction in such cases, enabling total retrieval of useful information in several different ways. The data is recorded any time there is a variation extrapolating the rules of the algorithm (which makes it more efficient than a simple dead band), or whenever there is a variation in quality (communication failure, hardware error, etc.).
Example 1: Chart with no compaction
Example 2: Chart with compaction: Basically the same amount of information of the previous chart, but in fewer points.
Data is stored in tables inside the Database, which in turn may contain a pre-defined period of information (from days to years). Periodically, the system will transfer to a backup table all the information extrapolating the intervals defined by the user.
Retrieval and Query
The data stored in the Database can be visualized via E3-based applications, Microsoft Excel® macros, or even user-defined programs, which can access the tables in the database directly.
To visualize data inside E3, there is the object E3Query, whose goal is to create queries for E3-supported databases in a graphic way. With E3 Storage, E3Query gains a new functionality with the randomness of changes in the controlled variables: consolidating the stored information.
Thus, E3Query allows you to select the tag(s) by name or complete path in the system, according to their type or location, and get the following information:
- Last stored value.
- Stored value compared to a certain date/time: right before, right after, interpolated (calculated), or exact value.
- Tag attribution (scales, engineering units, etc.).
- Values stored from a certain time/date on, or between dates.
- Values interpolated in fixed intervals in a certain periods.
- Calculated values.
- Interpolated values for a series of user-defined time/dates.
The result of queries made by E3 can be used in several objects:
- Charts (E3 Chart)
- Data Grid (E3 Browser)
- Reports (E3 Reports)
- RecordSets via VBScript (for calculation in scripts, etc.).
Visualization via Microsoft Office®
Subsequently, E3Storage will have a VBA interface and a set of macros available, so that the same data can be consulted and visualized from a suite of Microsoft Office products. In that case, all users connected simultaneously to E3 Server will need a harkey programmed for data visualization.
PlayBack and VCR Virtual functions
The PlayBack is an ActiveX object supplied with E3 that allows you to open any screen in the system and animate it with data from a query in the Database.
PlayBack Control has a series of fixed controls (scrollbar, start and end intervals, and time constant to accelerate or slow down the visualization). All open-screen links in PlayBack are replaced during this specific Viewer’s execution by the equivalent links in E3Storage, requiring no extra configuration. This allows a user group to use playback while another one continues visualizing and operating the system normally, in real time.
For a more complex process, or for screens mixing several types of objects (data and graphic objects), you could also use a separate E3 Server for your PlayBack, but retrieving data from the same database where the operational system is.