To set the time criteria on an historical data source | Item Time/Component Time | Start Time and Time Span
Historical data sources in Proficy Portal have a time component, which allows you to specify a start time or an interval in which to collect data. There are a number of other methods to update a time interval from which data is retrieved. For example, you can use the Quick Time control on an object or a display to update the time interval as required. For more information on time update interaction in objects and displays, see Time Management.
When you select a historical data source for an object that has a Quick Time control (Time, XY, Correlation charts and the Historian grid, Quick Analysis, or Thumbnail), you have the option of configuring the data item's Time tab options to configure the start time/time span of the data, or you can use the component time to determine the data's start time/time span. If multiple historical data sources are used for an object, then either all the sources use their item time to determine time span, or all the sources use component Quick Time to determine time span (when configuring data sources using the Edit Source dialog box). However, if you want each source to have a different configuration, you can make changes in the Advanced Settings dialog box. For more information, see Time Updates on Data Sources.
To avoid inaccuracies in the data being presented, when multiple historical data sources are used in expressions, component-level refresh settings are not available.
Objects that are set to use Item Time for their time initialization can have their start and end times modified with display-level Quick Time controls. When Quick Time on the display is set to relative or range, the times on the object are updated based on the current display time – not the machine's system time.
The start time of an historical data source determines when to start retrieving data. The time span determines the interval for the retrieved data; that is, amount of time from the start time that the data will be retrieved for. Time frames for data retrieval can also be set on the display and the object. Refer to Time Management for more information.
By default, the start time is set to the current time and date; however, you can set it to any time. When setting the start time, you can select from the following options:
After you have set the start time, you need to define a time span. By default, the time span is set to 1 hour. To change the time span, enter the required number(s) in the Days, Hours, Minutes, Seconds, and/or Millisecs field.
For information on the Sample Interval and Data Point Interval (specific to iHistorian data sources), see Sampling Interval and Data Point Interval and the Retrieval Mode.
