View Tag Trends and Raw Data

About this task

Historian Administrator can display trend data for a selected tag. Note that the tag trend should not be used for detailed data. Trend data is not supported for Array tags. Historian Administrator can also display the most recent ten raw samples for a selected tag.

Procedure

To display a trend of data for a selected tag:
1. Select a tag in the Tag Maintenance page.
2. Right-select the tag and select Trend.
  The page shown in the following figure appears.
  
  The page displays the trend of data over a selected time period.
3. Specify the time period and other parameters by selecting on the Criteria button at the bottom of the display.
  The Trend Criteria window shown in the following figure appears.
To select criteria for the trend display:
1. Enter the Start Time and End Time in the appropriate fields or browse to the times and select them.
2. In the Sampling field, select the data type to use for the display.
3. Enter a value for the time interval on the x-axis of the display.
4. Select the units for the time interval from the drop-down list (seconds, minutes, hours, or days).
5. Enter the criteria string.
  You can enter the sampling mode, calculation mode, and/or query modifiers in this field. Query modifiers are used to specify various ways of retrieving data from Historian. For example, you can request raw data with good quality only by specifying the criteria string as: RAWBYTIME#ONLYGOOD. The sampling mode specified with criteria strings takes precedence over the mode specified in the Sampling field.
6. Select OK.
7. Scroll back and forth on the x-axis time scale by selecting on the single and double left and right arrows at the bottom of the page. The single arrows move the duration ahead by 50% of the span. The double arrows move the duration ahead by 100% of the span.
To Display the Last Ten Raw Data Samples:
1. Select a tag in the Tag Maintenance page.
2. Right-select the tag and select Last 10 Values.